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HomeMy WebLinkAboutAPA4155pt1G 8 1- TECHNICAL REPORT NO . 1 ... ..,. pr pared lor THE OLD WEST REGIONAL COMMISSON by j,. WATER RESOURCES DIVISION-----------JULY IQ77 UaroNrANA DEPARTMeNT DF NATURAL R£SOURC£ & coNSCII~AnON ~ ,, by Bob Anderson, Assistant Administrator, WRD Phil Threlkeld, Land Resource Scientist, WRD Satish Nayak, Systems Analyst, CSD Hanley Jenkins, Environmental Planner, WRD TECHNICAL REPORT NO. 1 conducted by the Water Resources Division Montana Department of Natural Resources and Conservation 32 S. Ewing Helena, MT 59601 Bob Anderson, Project Administrator Dave Lambert, Editor for the Old West Regional Commission 228 Hedden Empire Building Billings, MT 59101 Kenneth A. Blackburn, Project Coordinator July 1977 1730 K Street, N. W. Suite 426 The Old West Regional Commission is a Federal-State partnership designed to solve regional economic problems and stimulate orderly economic growth in the states of Montana, Nebraska, North Dakota, South Dakota and Wyoming. Established in 1972 under the Public Works and Economic Development Act of 1965, it is one of seven identical commissions throughout the country engaged in formulating and carrying out coordinated action plans for regional economic development. COMMISSION MEMBERS State Cochairman Gov. Thomas L. Jud~e of Montana Alternate: Dean Hart Federal Cochairman George D. McCarthy State Members Gov. Edgar J. Herschler of Wyoming Alternate: Steve F. Freudenthal Gov. J. James Exon of Nebraska Alternate: Jon H. Oberg Gov. Arthur A. Link of North Dakota Alternate: Woody Gagnon Gov. Richard F. Kneip of South Dakota Alternate: Theodore R. Muenster COMMISSION OFFICES 201 Main Street Suite D Washington, D. C. 20006 202/967-3491 Rapid City, South Dakota 57701 605/348-6310 Suite 228 Heddon-Empire Building Billings, Montana 59101 406/657-6665 ii •: FOREWORD The Old West Regional Commission wishes to express its appreciation for this report to the Montana Department of Natural Resources and Conservation, and more specifically to those Department staff members who participated directly in the project and in preparation of various reports, to Dr. Kenneth A. Blackburn of the Commission.staff who coordinated the project, and to the subcontractors who also participated. The Yellowstone Impact Study was one of the first major projects funded by the Commission that was directed at investigating the potential environmental impacts relating to energy develop- ment. The Commission is pleased to have been a part of this important research. George D. McCarthy Federal Cochairman FIGURES TABLES ABBREVIATIONS USED IN THIS REPORT • PREFACE .•••• The River The Conflict • • • • • • • The Study Acknowledgements • • • • • INTRODUCTION Development Projections Basin Division • PART I. FUTURE WATER USE PROJECTIONS . PROJECTIONS OF COAL PRODUCTION FOR ENERGY Methods • Previous Projections • • . • • Energy-Development Alternatives • • •••••• o Low Level of Development o • • • o • • Intermediate Level of Development • • • • • • o • o High Level of Development • • • • • • • • • • • o o • Summary of Levels of Development • . • • • . Water Use Associated with Projected Energy Development PROJECTIONS OF IRRIGATED AGRICULTURE • Methods • • • • • • Identification of Irrigable Land • Calculation of Irrigation Costs .• • • • Farm Budgets and the Ability to Pay for Irrigation Irrigation and ~ater Depletion PROJECTIONS OF MUNICIPAL POPULATION GROWTH Montana Futures Process • . • • Economic Calculation . . • Demographic Calculation Municipal Population • • . . • Increased Water Use Associated with SUMMARY - i v - Population Growth . vii viii xi 1 1 1 3 4 5 5 6 9 11 14 14 15 17 22 22 26 31 37 38 38 38 45 51 56 56 57 57 59 59 63 PART II. HYDROLOGIC MODELING • SELECTION DF A WATER MODEL . Model Varieties • . • . . • • • The Utah State Model • • • • . • • . • Streamflow Synthesis and Reservoir Regulation (SSARR) ••••• HYD-2 SIMYLD-II . . . . . . . . . . . . The State Water Planning Model . • • • • Model Comparison • • • • ADAPTATION OF THE SWP How the SWP Model Was Used Calibration . . . . . . . . . . . . . Simulations Data Preparation The Annual and Monthly Models . Annual Model • Monthly Model • • • • • . Calibration of the Monthly Model and Controllable Variables Calibration Program and New Subroutines • Subroutine INITIA • • • . Subroutine EXPORT • • • • Subroutine SURFAC ••••• Subroutine COMPUT • • • • SIMQUAL--The Simulation Program • DEPLET • SURFAC • INITIA • MODIST • QUALTY . PRINT • • . • MEAN •• SORT and COMPAR PLOT • • SIMULATIONS Types of Simulations Scenarios • • • • . • • Area Simulations . . . . . . . . The Upper Yellowstone, Clarks,fork Yellowstone, and Kinsey Area Subbasins • • • • The Billings Area Subbasin • • • • • The Bighorn Subbasin • • • • • • • • • The Mid-Yellowstone Subbasin • • • • . The Tongue Subbasin • • • • • • . • The Powder Subbasin • • • • The Lower Yellowstone Subbasin • -v- . .. . 67 68 68 68 69 70 70 71 71 76 76 76 77 77 80 80 83 88 91 91 93 93 93 93 94 94 95 95 95 98 98 98 98 99 99 100 102 102 102 102 106 106 110 112 APPENDIXES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A. Projected Water Requirements in the Yellowstone River Basin in the year 2000 B. Coefficients and Constants for Subbasin Model Runs • C. Water Quality Regression Equations .•••• LITERATURE CITED 115 117 127 133 139 1. Yellowstone River Basin . . . . . . . . . . . . . 2. Map of strippable coal in the Yellowstone drainage basin 3. Base, low, intermediate, and high alternative futures for coal production •••••• 4. Montana futures process simulation-model structure • 5. Labor market areas in Montana 6. Calibration program subroutines . . . . . . . . . . . . . . 7. Simulation program subroutines •. 8. Schematic representation of TDS calculations • -vii- 7 12 30 56 58 91 94 96 l. Definition of strippable coal . . . . . . . . . 2. Coal production in 1975 and 1980 in the Yellowstone Basin based on coal sales contracts 3. Stabilized coal production in the Yellowstone River Basin 4. Planned coal production by company, mine and year . . . . 5. Coal production under low-level development, Yellowstone Basin • • • • • • • 6. Location of coal conversion facilities through the year 2000, low development level, by Yellowstone River subbasins • • • • • • • • • • • • • • • . . . 7. Coal ~onnage location by Yellowstone River subbasins, low-level development 1980, 1985, 2000 •••••••••••• 8. Coal production for consumption-under intermediate-level devel- opment, Yellowstone Basin •.•••••• 9. 10. Location of coal conversion facilities through year 2000, intermediate development level, by Yellowstone River subbasins •••••••••••••• Coal tonnage location by Yellowstone River subbasins, intermediate level development, 1980, 1985, 2000 11. Coal production for consumption under high-level development, Yellowstone Basin • • • • • • • • • 12. Location of coal conversion facilities through the year 2000, high development level~ by Yellowstone River subbasins •••••.••••••••• 13. Coal tonnage location by Yellowstone River subbasins, high- level development, 1980, 1985, 2000 . . . . 14. Coal production for consumption under three levels of development, Yellowstone River Basin, through the year 2000 . . . . . . . . . . 15. Coal conversion in the Yellowstone Basin in 2000 16. Annual water and coal requirements for coal processes . -viii- . . . . . . . 11 16 17 . . . 18 19 20 21 23 23 24 25 27 28 . . . 29 32 33 . . . 17. Water use in coal m~n~ng and electrical generation by 1980 by Yellowstone River subbasin under various levels of development • • • • • • • . . • • • • • • • • • • • • . . • 34 18. Water use in coal mining, transportation, and conversion processes by 1985 by Yellowstone River subbasin under various levels of development • • • • . • • • . • • . . • • • . 35 19. Water use in coal mining, transportation, and conversion processes by 2000, by subbasin under various levels of development . • • • • • • • • . . • • . • 36 20. Land classification specifications by soil or land characteristics • • • . • . • • • . . • • • • • . • 39 21. Irrigable acreage in Yellowstone River subbasins by lift and pipe length • • • . • • . . 40 22. Concrete pipeline costs • 43 23. Steel pipeline costs 43 24. Annual water delivery costs 25. Center-pivot irrigation costs 26. Inventory of buildings~ machinery and equipment; investment, repair, depreciation and taxes for a hypothetical 44 44 320-acre farm . . . . . . . . . . . . . . . . . . . 46 27, Miscellaneous fixed costs for a hypothetical 320-acre farm 47 28. Farm prerequisites (house, garage, well) 47 29. Variable costs per irrigated acre by crop • 48 30. Irrigated-crop production and sales per acre 49 31. Farm budget summary with management allowance 50 32. Cropping patterns by subbasin, 320-acre farm . • . • . • 5'1 33. Costs and returns by subbasin 320-acre farm 53 34. Payment capacity available for pumping 53 35. Maximum pumping distance for various lifts 53 36. Feasibly irrigable acreage by lift and pipeline length, high-level development . • • • • • . • • • • • • • . • • . . 54 37. The increase in water depletion for irrigated agriculture by 2000 by subbasin • . • • • . . . • . . • • • . • • 55 38. Permanent, direct energy-related employees in the Yellowstone basin, 1985 and 2000 . 39. Population simulations for low, medium, and high energy development • • • . . • • • • . • • • • • 40. Population increases and water depletion in the Yellowstone River Basin in 1985 and 2000, according to levels of energy development • • • • • • . • • • • • • • 41. Water requirements by demand source in the Yellowstone River Basin under three levels of development in 2000 42. Increased water requirements for coal development in the Yellowstone Basin in 2000 • • • • 43. Model comparison 44. Suggested model evaluation criteria • 45. Model coefficients 46. Percentage by month of TDS returning to streamflow 47. Billings area subbasin water requirements • 48. Outflow of the Billings area subbasin . . . 49. Average out flow and TDS of Billings area subbasin . 50. Bighorn subbasin water requirements . . . . 51. Outflow and TDS of the Bighorn subbasin . . . . . . 52. Mid-Yellowstone subbasin water requirements . . 53. Outflow of the Mid-Yellowstone subbasin . . . 54. Average outflow and TDS of Mid~Yellowstone subbasin • 55. Tongue subbasin water requirements 56. Outflow of the Tongue River subbasin 57. Average outflow and TDS of Tongue subbasin 58. Powder subbasin water requirements 59. Outflow and TDS of the Powder subbasin 60. Lower Yellowstone subbasin water requirements •. 61. Outflow of the lower Yellowstone subbasin •• 62. Average outflow and TDS of the lower Yellowstone subbasin -x- . . . . . . . . . . . . 60 61 62 64 65 73 75 82 97 103 104 104 105 105 106 107 108 108 109 109 111 112 113 114 114 af af/acre af/y b/d cfs em FAA ft gal/d/pers ha 3 hm 3 hm /y hr in kq km kwh lb LMA m3 m /sec M.C.R. mg/1 mi millimhos/cm mmaf mmcfd mmt/y mw NGPRP SMSA SSARR SWP t/d tdh TDS USGS whc -xi - acre-feet acre-feet per acre acre-feet per year barrels per day cubic feet per second centimeter Federal Aviation Authority feet gallons per day per person hectare cubic hectometer cubic hectometers per year hour inch kilogram kilometer kilowatt hour pound Labor Market Area meter cubic meters per second mean cover rating milligram per liter mile unit of electrical conductivity per centimeter million acre-feet million cubic feet per day million ton~ per year megawatts Northern Great Plains Resource Program standard metropolitan statistical area Steamflow Synthesis and Reservoir Regulation State Water Planning Model tons per day total dynamic head total dissolved salts United State Geological Survey water holding capacity THE RIVER ihe Yellowstone River Basin of southeastern Montana, nor~hern Wyoming, and western North Dakota encompasses approximately 180,000 km (71,000 square miles), 92,200 (35,600) of them in Montana. Montana's portion of the basin comprises 24 percent of the state's land; where the river crosses the border into North Dakota, it carries about 8.8 million acre-feet of water per year, 21 percent of the state's average annual outflow. The mainstem of the Yellowstone rises in northwestern Wyoming and flows generally northeast to its confluence with the Missouri River just east of the Montana-North Dakota border; the river flows through Montana for about 550 of its 680 miles. The major ·tributaries, the Boulder, Stillwater, Clarks Fork, Bighorn, Tongue, and Powder rivers, all flow in a northerly direction. The western part of the basin is part of the middle Rocky Mountains physiographic province; the eastern section is located in the northern Great Plains (Rocky Mountain Association of Geologists 1972). THE CONFLICT Historically, agriculture has been Montana's most important industry. In 1975 over 40 percent of the primary employment in Montana was provided by agriculture (Montana Department of Community Affairs 1976). In 1973, a good year for agriculture, the earnings of labor and proprietors involved in agricultural production in the fourteen counties that approximate the Yellowstone Basin were over $141 million, as opposed to $13 million for mining and $55 million for manufacturing. Cash receipts for Montana's agricultural products more than doubled fro~ 1968 to 1973. Since that year, receipts have declined because of unfavorable market conditions; some improvement may be in sight, however. In 1970, over 75 percent Qf the Yellowstone Basin's land was in,agricultural use (State Conservation Needs Committee 1970). Irrigated agriculture is the basin's largest water use, consw~ing annually about 1.5 million acre-feet (af) of water (Montana DNRC 1977). There is another industry in the Yellowstone Basin which, though. it con- sumes little water now, may require more in the future, and that is the coal development industry. In 1971, the North Central Power Study (North Central Power Study Coordinating Committee 1971) identified 42 potential power plant sites in the five-state (Montana, ~orth and South Dakota, Wyoming, and Colorado) northern Great Plains region, 21 of them in Montana. These plants, all to be fired by northern Great Plains coal, would generate 200,000 megawatts (mw) of electricity, consume 3.4 million acre-feet per year (mmaf/y) of water, and result in a large population increase. Administrative, economic, legal, - 1 - and technological considerations have kept most of these conversion facilities, identified in the ~orth Central Power Study as necessary for 1980, on the drawing board or in the courtroom. There is now no chance of their being completed by that date or even soon after, which will delay and diminish the economic benefits some basin residents had expected as a result of coal development. On the other hand, contracts have been signed for the mining of large amounts of Montana coal, and applications have been approved not only for new and expanded coal mines but also for Colstrip Units 3 and 4, twin 700-mw, coal-fired, electric generating plants. And in July 1979 the U.S. Department of Energy released a study concluding that 36 synthetic fuel plants could be constructed in Montana; together, they would use 468,000 acre-feet of water annually. In 1975, over 22 million tons of coal were mined in the state, up from 14 million in 1974, 11 million in 1973, and 1 million in 1969. By 1980, even if no new contracts are entered, Montana's annual coal production will be about 35 million tons. Coal reserves, estimated at over 50 billion economically strippable tons (Montana Energy Advisory Council 1976), pose no serious con- straint to the levels of development projected by this study, which range from 186.7 to 462.8 million tons stripped in the basin annually by the year 2000. Strip mining itself involves little use of water. How important the energy indust~y becomes as a water user in the basin will depend on: 1) how much of the coal mined in Montana is exported, and by what means, and 2) by what process and to what end product the remainder is converted within the state. If conversion follows the patterns projected in this study, the energy industry will use from 48,350 to 326,740 af of water annually by the year 2000. A third consumptive use of water, municipal use, is also bound to increase as the basin population increases in response to increased employment opportunities in agriculture and the energy industry. Can the Yellowstone River satisfy all of these demands for her water? Perhaps in the mainstem. But the tributary basins, especially the Bighorn, Tongue, and Powder, have much smaller flows, and it is in those basins that much of the increased agricultural and industrial water demand is expected. Some impacts could occur even in the mainstem. What would happen to water quality after massive depletions? How would a change in water quality affect existing and future agricultural, industrial, and municipal users? What would happen to fish, furbearers, and migratory waterfowl that are dependent on a certain level of instream flow? Would the river be as attractive a place for recreation after dewatering? One of the first manifestations of Montana's growing concern for water in the Yellowstone Basin and elsewhere in the state was the passage of significant legislation. The Water Use Act of 1973, which, among other things, mandates the adjudication of all existing water rights and makes possible the reservation of water for future beneficial use, was followed by the Water Moratorium Act of 1974, which delayed action on major applications for Yellowstone Basin water for three years. The moratorium, by any standard a bold action, was prompted by a steadily increasing rush of applications and filings for water (mostly for industrial use) which, in two tributary basins to the Yellowstone, exceeded supply. The DNRC's intention -2- during the moratorium was to study the basin's water and related land resources, as well as existing and future need for the basin's water, so that the state would be able to proceed wisely with the allocation of that water. The study which resulted in this series of reports was one of the fruits of that intention. THE STUDY The Yellowstone Impact Study, conducted by the Water Resources Division of the Montana Department of Natural Resources and Conservation and financed by the Old West Regional Commission, was designed to evaluate the potential physical, biological, and water use impacts of water withdrawals and water development on the middle and lower reaches of the Yellowstone River Basin in Montana. The study's plan of operation was to project three possible levels of future agricultural, industrial, and municipal development in the Yellowstone Basin and the streamflow depletions associated with that develop- ment. Impacts on river morphology and water quality were then assessed, and, finally, the impacts of altered streamflow, morphology, and water quality on such factors as migratory birds, furbearers, recreation, and existing water users were analyzed. The study began in the fall of 1974. By its conclusion in December of 1976, the information generated by the study had already been used for a number of moratorium-related projects--the EIS on reservations of water in the Yellowstone Basin, for example (Montana DNRC 1976). The study resulted in a final report summarizeing ~11 aspects of the study and in eleven specialized technical reports: Report No. 1 Report No. 2 Report No. 3 Report No. 4 Report No. 5 Report No. 6 Report No. 7 Future Development Projections and Hydrologic Modeling in the Yellowstone River Basin, Montana. The Effect of Altered Streamflow on the Hydrology and Geomorphology of the Yellowstone River Basin, Montana. The Effect of Altered Streamflow on the Water Quality of the Yellowstone River Basin, Montana. The Adequacy of Montana's Regulatory Framework for Water Quality Control Aquatic Invertebrates of the Yellowstone River Basin, Montana. The Effect of Altered Streamflow on Furbearing Mammals of the Yellowstone River Basin, Montana. The Effect of Altered Streamflow on Migratory Birds of the Yellowstone River Basin, Montana. -3- Report No. 8 Report No. 9 Report No. 10 Report No. 11 The Effect of Altered Streamflow on Fish of the Yellowstone and Tongue Rivers, Montana. The Effect of Altered Streamflow on Existing Municipal and Agricultural Users of the Yellowstone River Basin, 1·1ontana. The Effect of Altered Streamflow on Water-Based Recreation in the Yellowstone River Basin, Montana. The Economics of Altered Streamflow in the Yellowstone River Basin, Montana. ACKNOWLEDGEMENTS Bruce Finney, of the Montana Department of Community Affairs, provided the population projections used in Part I. Derwood Mercer, of the Bureau of Reclamation, provided the cost information used in projecting farm budgets in Part I, as well as the equations and cost information used in projecting pumping cost. DNRC personnel providing assistance were George Cawlfield, who helped with the hydrologic modeling reported in Part II and reviewed and revised Part II; John Jarvie, who also helped with Part II; Glen Smith, who superivsed the preparation of the irrigable land projections, and Elna Tannehill, who helped with the economic analysis used in those projections; Gary Fritz, administrator of DNRC's Water Resources Division, who provided guidance and review; Mark Nicholson, Ron Schleyer, Shari Meats, Marianne Melton, and Karen Renne, who performed editing tasks; and Janet Cawlfield, Lynda :~owell, and Kris Macintyre, typists. Graphics were coordinated and performed by Gary Wolf, with the assistance of Dan Nelson. The cover was designed and executed by D.C. Howard. -4- DEVELOPMENT PROJECTIONS The principal objective of the Yellowstone Impact Study was to evaluate potential environmental impacts resulting from future water development likely to occur on the Yellowstone River. Achievement of this objective was handi- capped throughout the study by two inherent problems. First, the Yellowstone, because it is a free-flowing river, is not controllable. Researchers were unable to alter the streamflows and observe changes. Thus, all studies had to be made under the circumstances nature provided, which were less than ideal for a low-flow study such as this--1975 was a year of record high flows and 1976 a year of moderate flows. A second problem, a subject of this report, was the imperfect knowledge of the magnitude and type of future water developments. The purpose of this part of the Yellowstone Impact Study was to resolve that problem by projecting future resource development and economic growth in the basin and the amount of water that development would require. The material presented in this report is basic to the entire study; the other ten technical reports project the types and amounts of impact that would be expected in the Yellowstone Basin if the water depletions projected in this report were to occur. If major water developments occur, they are expected to be of two types: agricultural and energy-industrial. (It was assumed that future agricultural water use will be for irrigation.) Municipal water use, to be determined by the two major types of development, will be one order of magnitude less. Part I of this report projects the amount of development of each of these three types that might occur in the basin and how much water would be re- quired. Part II projects, through a computer simulation, what the streamflow in the Yellowstone River and its major tributaries would be if the projected amounts of water were withdrawn. The projections made throughout this report are projections of what might happen, based on particular assumptions; they are not predictions of what will happen. The irrigation projections are uncertain because of the unknown future of many factors, especially crop prices. The energy development pro- jections are even more uncertain. Although the extent of the coal resource is well known, the future demand for development of that resource is not, and no attempt is made in this report to predict future demand for coal. Rather, a high level of development is defined as the scenario that would occur if the State of Montana were to actively promote coal development. Regardless of the rigor of the prediction methodology, it must be based on numerous assumptions that are plagued with uncertainty. Only one of these assumptions may turn out to involve the controlling factor, but it is impossible at this time to identify that factor, let alone the demand's - 5 - elasticity to that factor. Rather, this study assumed a "What if •. 7" approach. If coal development occurs at the high level, what will be the impacts of that level of development? If they are unacceptable, then the state can attempt to constrain the development at a lower level through in- stitutional means. If it is naive to assume that the state can and will exert such control, then the whole exercise is fruitless. BASIN DIVISION To facilitate this study, thi Yellowstone River Basin was divided into the following nine subbasins : 1) The Upper Yellowstone Subbasin, which consists of the basins of the Yellowstone mainstem from the Montana-Wyoming border to Laurel (43B and 43QJ), the Shields River (43A), the Boulder River (43BJ), Sweet Grass Creek (43BV), and the Stillwater River (43C); 2) The Clarks Fork Yellowstone Subbasin (43D) ;! 3) The Billings Area Subbasin, which consists of the basins of the Yellowstone River (43Q) and Pryor Creek (43E); 4) The Bighorn Subbasin, which includes the basins of the Bighorn (43P) and Little Bighorn rivers (430); 5) The Mid-Yellowstone Subbasin, which consists of the basins of Rosebud Creek (42A) and of the Yellowstone mainstem between the confluences of the Bighorn and Yellowstone rivers (42KJ); 6) The Tongue Subbasin (42B and 42C); 7) The Kinsey Area Subbasin, the smallest of the nine subbasins con- sidered in this study, which consists of the basin of the Yellow- stone mainstem between the confluences of the Tongue and Yellowstone rivers and the Powder and Yellowstone rivers (42K); 8) The Powder Subbasin, which includes the basins of the Powder (42J) and Little Powder rivers (42I); and 9) The Lower Yellowstone Subbasin, which consists of the basins of O'Fallon Creek (42L) and of the Yellowstone mainstem from the confluence of the Powder and Yellowstone rivers to the Montana-North Dakota border (42M). Figure 1 shows the nine subbasins with their boundaries. The subbasins approximate the basins of the major tributaries of the Yellowstone River, allowing each of the major tributaries to be modeled for the Yellowstone Impact Study. lThe numbers in parentheses correspond to the basin numbers used to indi- cate hydrologic basins in An Atlas of Water Resources in Montana by Hydrologic Basins (MWRB 1970). -6- YEllowsTONE CoNTRibuTiNG RiVER 1 2 3 4 5 6 7 8 9 Upper Yellowstone Clarks Fork Yellowstone Billings Area Bighorn Mid-Yellowstone Tongue Kinsey Area Powder Lower Yellowstone 0 10 20 u-u-u I 0 10 20 wu------1 YELLOWSTONE NATIONAL .PARK 40 I 40 I ' ) I ( RIVER BASIN BAsiNs 60 80 100 Miles I I I 60 80 100 Kilometers I I I N YELLOWSTONE RIVER BASIN GARFIELD I L-, ROSE . , iS L-----r.L I COLSTRIP I ---. --{ e I L \ ~ ee~ ------\-.., ~ cr ' I I ~-:. I r ---, I ---L, \ I ' ' ---1 g ... ~ 1 tJ: McCONE DAWSON I L--, PRAIRIE \ I ,,"' I ' I ' ) r- \ I \ \ I C U s\T E R I \ I I , GLENDIVE) J J 'tj > ~ 0 ~ > -----L.. ._ __ _ WYOMING by Bob Anderson Phil Threlkeld Hanley Jenkins -9- The low-sulfur coal in southeastern Mbntana currently is in demand. The increasing world price of oil, decreasing domestic supplies of crude oil and natural gas, and the goal of United States energy self-sufficiency have increased the market value of many domestic coal reserves, including tvlontana's. Averiet (1974) estimated that coal reserves in Montana might be as high as 448.6 billion tons of lignite, subbituminous, and bituminous coal. Estimates by the Bureau of Reclamation (USDI 1972) indicate that approxi- mately 75 percent of this total lies within 1,000 ft of the surface. The Montana reserve is part of the vast Fort Union coal region (considered the world's largest), which contains approximately 40 percent of the United States coal reserve (Montana Coal Task Force 1973) and underlies parts of western North Dakota, northwestern South Dakota, northeastern Wyoming, southeastern Saskatchewan, and eastern Montana. Strip mining is used to recover these coal reserves. Economically, underground mining has a weak competitive position in Montana. Compared to strip mining, capital requirements are higher for underground mining, and productivity per miner is low. The actual cost of mining is, as a result, far higher. In the West, whether a coal deposit is strippable commonly is determined according to the depth criteria in table 1. Matson (1974) estimated that 42.5 billion tons of strippable coal underlies eastern Montana. Figure 2 locates strippable coal reserves in the Montana portion of the Fort Union coal region. Table 1. Definition of strippable coal. Thickness of Maximum Overburden Strippable Beds ( ft) Depth ( ft) 0 -10 0 -100 10 -25 0 -150 25 -40 0 -200 more than 40 0 -250 SOURCE: Montana College of Mineral Science and Technology 1973 -11- Because of the low cost of strip m1n1ng, use of western coal reserves for power and fuel is highly profitable for mining companies. There are three major markets expected to buy Montana coal from the companies: 1) power-plant operators in the South, Midwest, and Pacific Northwest; 2) pro- ducers of synthetic fuels from coal at mine-mouth conversion facilities, and 3) power-plant operators at mine-mouth plants in Montana. This report does not attempt to estimate exactly the demand these three markets might generate for southeastern Montana coal, but postulates certain quantitative increases in production as the general response to demand for energy. METHODS This study develops coal-production projections for energy development in Montana's portion of the Yellowstone River Basin. Three levels of develop- ment are postulated for five consuming sectors of the national economy: household and commercial, industrial, electrical generation, synthetic fuel, and export for processing or ~onsumption elsewhere. The projections span the years 1975 through 2000. The intent is not to predict the future but rather to present alternative futures (levels of development) in coal pro- duction. After postulating levels of coal development, the study calculated industrial wate~ use re~uirements tb aid in determining the potential impacts of altered streamflows on existing consumers of water and on recreation, water quality, the ecosystem, and the economy (see reports 2 through 11 in this series). PREVIOUS PROJECTIONS A humber of private-organizations and government agencies have projected coal production and related economic development in Montana. A few of those studies are identified below. 1) The Federal Energy Administration's Project Independence Report (1974) constructed a model of supply and demand for coal in the Northern Great Plains. Because the assumptions on which the model is based are unknown, comparison or use of the reported data is difficult. 2) A Northern Great Plains Resource Program (NGPRP) work group issued a na- tional report on regional energy considerations in 1974, which presented a series of coal-development projections for the NGPRP. Some of those projections are used extensively in this report and are discussed where applicable. The NGPRP is intergovernmental and involves the states of the Northern Great Plains region (Montana, Wyoming, North Dakota, South Dakota, and Nebraska) and three federal agencies (Environmental Protection Agency, Department of the Interior, and Department pf Agriculture) with responsibilities for problems that might arise from coal and energy development in the region. -12- YEllowsTONE RIVER BASIN STR1ppAblE CoAl REsERVES Coal Res.erves SOURCE: Montana College of Science and Technology 1973. 0 10 20 40 60 80 100 Miles UUitU1£~t=~1 ...... .t1 ======j1 ...... .t'======jl 0 10 20 40 60 80 100 Kilometers ~~~=1----t1 ==~1 .... t1==~1 ! MUSSELSHELL G 0 L D-EN \ I WHEATLAND I I ____ T ___ j VALLEY I .----~-L_ I l ------'1 - --~, _ _,___ Y E L L 0 W S T 0 N E ') NATIONAL PARK ( N BIG H ESERVATION YELLOWSTONE RIVER BASIN GARFIELD WYOMING McCONE I \~ -----, I • , GLENDIVE) \ J ! 3) The Montana University Coal Demand Study (MUCDS) report entitled Projections of Northern Great Plains Coal.Mining and Energy Con- version Development 1975-2000 A.D. considered demand for Northern Great Plains Resource Program coal associated with two primary facilities--electric generation and synthetic natural gas. The . MUCDS attempted to (l) identify what factors will influence NGP coal development, (2) indicate the key variables determining de- velopment, and (3) establish quantitatively how the levels of development would be altered .. if th~ variables were to change. Th~ MUCDS proj~ctions for synthetic natural gas production are reflected in the projections of the Yellowstone Impact Study. 4) In September 1975, the Missouri River Basin Commission began the Yellowstone Level B Study, a· two-year planning study to develop general information on water and related land resources in the Yellowstone River Basin and adjacent coal areas. The Commission hired the Harza Engineering Eompany to develop three alternative coal-mining and energy-conversion levels for the'years 1985 and 2000 reflecting demand and suppl~ of energy nationally and within · the Yellowstone Basin. ENERGY-DEVELOPMENT ALTERNATIVES This report incorporates many of the aforementioned coal development estimates to provide a fresh and realistic estimate of potential levels of coal and energy development in· southeastern Montana and the rest of the Yellowstone Basin. As with any projection on this subject, predicting the levels of development is speculation because of the major unknowns--future demand and cost for coal, and the extent that public policy will allow coal development to proceed. Because the number of possible alternative futures is great, this study chose three-possibilities that might arise from the influences on coal de- velopment in the Yellowstone River Basin. ·Two of these--low and high levels of development--were chosen to represent limited development and highly advanced development of coal resources. An intermediate alternative fills the gap between the low-lev~l and the advanced-development alternatives. A fourth and lowest alternative--gradually rising coal production to 1980 and practically stable production thereafter--was examined (see tables 2 and 3),,but it is not considered to be a practical possibility in view of the pressures tending to encourage coal development in the United States. Only if alternative sources of energy (such as the sun) or energy conservation prove·to be more economically attractive than coal conversion is there likely to be any such leveling off of Montana coal production within a decade. For this study, a gradual rise in coal production is assumed to be inevitable in view of existing coal sales contracts signed by six companies operating in the Yellowstone River Basin. Alternative levels of development presented here are based on data from the Montana Energy Advisory Council (1974). Existing data were sup- plemented and updated in response to more recent production figures. Coal -15 - production is given in million short tons (mmt) unless noted otherwise. (A short ton is equal to 2,000 pounds.) Table 2 displays estimates of coal production for 1975 and 1980 based on existing coal sales contracts signed by the six companies. The coal production tonnages have been reassembled according to two uses: electrical generation in southeastern Montana and export out of Montana. Most coal mined in Montana until 1980 under existing contracts will be shipped out of state for use by Midwestern and Southern utilities in electrical generation. Table 2. Coal production in 1975 and 1980 in the Yellowstone Basin based on coal sales contracts (mmt). Coal for Electrical Generation in Montana Mining Company 1975 1980 Knife River Coal Co. (for Sidney plant) 0.32 0.30 Western Energy Co. (for Corette plant in Billings) 0.50 0.50 Western Energy Co. (for Colstrip) 0.40 3.20 TOTAL 1.22 4.00 Coal for Export Western Energy Co. 4.33 10.00 Decker Coal Co. 8.25 13.90 Westmoreland 4.00 6.50 Peabody 3.00 3.00 Shell Oil Co. 8.00 TOTAL 19.58 41.40 -16- Synthetic-fuel facilities could become part of the Montana stabilized coal-production alternative in the year 2000. In meeting the gap between supply and demand for gas, it might be necessary to construct a synthetic gas plant capable of producing 250 million standard cubic feet per day (mmcf/d). It would consume approximately 7.6 mmt of coal per year. The product of stabilized coal production during the remaining years of the century would be consumed in the five major coal-consuming sectors of the national economy as indicated in table 3. In this and all other alternatives, consumption in the household-commercial and industrial sectors is insignifi- cant after 1975 in comparison with the other consuming sectors. Table 3. Stabilized coal production in the Yellowstone River Basin 1971 1975a Consuming Sector (Actual) (Actual) 1980 1985 2000 Household and Commercial 0.1 0.2 insig. insig. insig. Industrial 0.1 0.2 insig. insig. insig. Electrical Generation 0.8 0.8 4.0 4.0 4.0 Synthetic Fuel 0 0 0 0 7.6 Exports 6.1 21.0 41.4 41.4 41.4 TOTAL 7.1 22.2 45.4 45.4 53.0 a Extrapolated from Montana 01~11C 1976, p. 83, table 5.6. LOW LEVEL OF DEVELOPMENT The study assumes that under low-level development coal production will be limited to meeting Montana demands and supplying existing and planned delivery contracts. The projections were derived from a combination of data compiled by the Montana Energy Advisory Council (1974), the Northern Great Plains Resource Program (1974b), and by companies planning coal production for export. (Existing data were supplemented or updated since the MEAC and NGPRP studies in respo~se to more recent production figures as they became available.) Table 4 shows coal production planned for export, by three mining com- panies through the year 2000. These companies have leases for the coal but are still engaged in planning. Although some contracts are signed, acceptance of environmental impact statements for the mines and agreements on royalties are still pending. Combining this with information on existing sales contracts (table 2) and coal production forecast by NGPRP (corrected to make it applicable to -17- Table 4. Planned coal production by company, mine, and year (mmt) Production Company and Actual Planned thne 976 1977 1978 1980 1981 1982 1983 1984 1985 2000 SHELL OIL co.a Youngs Creek 0 0 0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 Tanner Creek 0 0 0 2.0 4.0 4.0 4.0 4.0 8.0 8.0 \~ol f Mountain 0 0 0 2.0 2.0 4.0 4.0 4.0 4.0 8.0 Squirrel Creek 0 0 0 0 0 0 0 0 2.0 8.0 DECKER COAL CO. East Decker 0 0 2.25 6.6 6.6 6.6 6.6 6.6 6.6 6.6 North Extension 0 0 0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 WESTMORELAND Crow-Ceded Lands 4.0 4.5 4.5 4.0 4.0 10.0' 10.0 10.0 10.0 15.0 TOTAL 4.0 4.5 6.75 24.6 26.6 34.6 34.6 34.6 40.6 55.6 NOTE: Production shown here is in addition to the existing contracts tabulated in table 2. Derived from 1975 data, partially updated in 1979. aThe Shell Oil Company (Ireson 1979) says plans for these mines are held in abeyance until litigation and negotiation with the Crow Tribe are complete. -18 - the Yellowstone Basin only) yields a complete projection of coal production to meet low-level consumption demands through the end of the century. It is presented in table 5. The Yellowstone Impact Study focused in particular on the years 1980, 1985, and 2000. Under the low-level development assumptions, there would be 66 mmt mined for export in 1980; 114 mmt in 1985; and 171 mmt mined for export in 2000. Electrical generation facilities are projected to consume 4.0 mmt of coal basin-wide in 1985 and 8.0 mmt in the year 2000. Another 7.6 mmt is expected to be consumed by the single coal gasification plant envisioned to be in operation by the end of the century under the assumptions of low- level development. Table 6 indicates that, through 1985, only the Mid- Yellowstone Subbasin would have energy conversion facilities. By 2000, the Tongue Subbasin would have a 500-mw electrical generating plant. Table 5. Coal production in the Yellowstone Basin under low-level development (mmt). 1971 1975 1985b Consuming Settor (Actual) (Actual) 1980a Household- Commercial 0.1 0.2 insig. insig. Industrial 0.1 0.2 insig. insig. Electrical Generation 0.8 0.8 4.0 4.0 Synthetic Fuels 0 0 0 0 Export from Montana 6.1 21.0 66.0 114.0 TOTAL 7.1 22.2 69.8 118.0 aExisting contracts and planned exports. bNGPRP data plus coal exports. cNGPRP data plus coal exports. insig. insig. 8.0 7.6 171.1 186.7 Table 7 shows coal production by subbasin during the rema1n1ng years of the century under the low-level development projections. The production figures shown in table 5 thus appear in the basin totals for each of the consumptive uses shown in the tables--electrical generation, gasification, production of synthetic crude oil and fertilizer--plus exports. Under the assumptions of low-level coal development in the Yellowstone Basin, export of coal by slurry pipeline would play no part in coal exports through the year 2000. -19- Table 6. Location of coal conversion facilities through the year 2000, low-level development 1000-mw 250-mmdfd 100,000-b/d 2300-t/d Electric Synthetic Synthetic Fertilizer Generating Gas Plants Crude Plants Plants Plants 1980 Mid-Yellowstone 1 0 0 0 All Others 0 0 0 0 TOTAL 1 0 0 0 1985 Mid-Yellowstone 1 0 0 0 All Others 0 0 0 0 TOTAL 1 0 0 0 2000 Tongue 0.5 0 0 0 Mid-Yellowstone 1.5 1 0 0 All Others 0 0 0 0 TOTAL 2 1 0 0 -20- Table 7. Coal tonnage location by Yellowstone River subbasins, low -level development, 1980, 1985, 2000 (mmt/y) Electric Subbasins Generation Gasification Syncrude Fertilizer Export a Total 1980 Tongue 0 0 0 0 29.7 29.7 Mid-Yellowstone 4.0 0 0 0 23.1 27.1 Powder 0 0 0 0 6.6 6.6 Bighorn 0 0 0 0. 6.6 6.6 TOTAL 4.0 0 0 0 66.0 70.0 1985 Tongue 0 0 0 0 51.3 51.3 Mid-Yellowstone 4.0 0 0 0 39.9 43.9 Powder 0 0 0 0 11.4 11.4 Bighorn 0 0 0 0 11.4 11.4 TOTAL 4.0 0 0 0 114.0 118.0 2000 Tongue 2.0 0 0 0 77 .o 79.0 Mid-Yellowstone 6.0 7.6 0 0 59.9 73.5 Powder 0 0 0 0 17.1 17.1 Bighorn 0 0 0 0 17.1 17.1 TOTAL 8.0 7.6 0 0 171.1 186.7 a All export at the low level of development was assumed to be by unit train rather than slurry pipeline. -21 - INTERMEDIATE LEVEL OF DEVELOPMENT The study assumes that under intermediate-level development coal production and energy development will occur midway between the projections for low and high levels of development. The intermediate level of development may or may not be the most likely projection and should be regarded simply as one possibility within the defined range for future coal and energy develop- ment. Coal tonnages that would be mined through the end of the century under assumptions for intermediate-level development are displayed in table B. The amounts of coal used by the consuming sectors in 1975 are based on data in table 2 on long-term coal contracts. Each estimate for electrical generation, synthetic fuel, or export for 1980, 1985, or 2000 in table 8 is the mean between the low and high levels of development. The study assumes that under intermediate-level coal development, 20 percent of coal exports will be by slurry pipeline by the year 2000. I Table 9 indicates that under intermediate level development, only the Mid-Yellowstone Subbasin would have energy conversion facilities in 1980 and 1985. The trend would be toward gradual additions to the mine-mouth electrical generation capacity of the Mid-Yellowstone Subbasin, with three 1,000-mw generating plants and one 250-mmcf/d synthetic gas plant likely by the year 2000. By that time, there would also be two 1000-mw electrical generating plants in the Tongue River subbasin and one in the Powder River subbasin. Table 10 shows coal production by subbasin during the remaining years of the century under the intermediate-level development projections The production figures shown in table 8 appear in the basin-wide totals for each of the consumptive uses shown in the table--electrical generation, gasifica- tion, production of synthetic crude oil and fertilizer, and exports. By the year 2000, under the assumptions of intermediate-level coal development in the Yellowstone Basin, 20 percent of coal exports would be by slurry pipeline (see "Export" column, table 10). HIGH LEVEL OF DEVELOPMENT The high-level of development estimate shows the extent to which development of Yellowstone River Basin coal reserves would be pursued if coal were used to fuel U.S. energy self-sufficiency and if its substitutes-- energy conservation, oil, natural gas, nuclear power, and alternative energy sources--were unable to supply substantial shares. Table 11 shows coal production tonnage to meet demand under high-level development. -22- Table 8. Coal production in the Yellowstone Basin under the intermediate level of development (mmt) 1971 1975 Consuming Sector (Actual) (Actual) 1980 1985 ' 2000 Household and Commercial 0.1 0.2 insig insig insig Industri<:tl 0.1 0.2 insig insig insig Electrical Generation 0.8 0.8 4.0 8.0 24.0 Synthetic Fuel 0 0 0 0 7.6 Exports 6.1 21.0 68.6 154.6 293.2 TOTAL 7.1 22.2 72.6 162.6 324.8 Table 9. Location of coal conversion facilities through the year 2000, intermediate level of development 1000-mw 1,000-b/d Electric 250-mmcf/d Synthetic 2,300-t/d Generating Synthetic Crude Fertilizer Subbasin Plants Gas Plants Plants Plants 1980 Mid-Yellowstone 1 0 0 0 All others 0 0 0 0 TOTAL 1 0 0 0 1985 Mid-Yellowstone 2 0 0 0 All others 0 0 0 0 TOTAL 2 0 0 0 2000 Tongue 2 0 0 0 Mid-Yellowstone 3 1 0 0 Powder 1 0 0 0 All others 0 0 0 0 TOTAL 6 1 0 0 -23- Table 10. Coal tonnage location by Yellowstone River subbasin, intermediate level of development, 1980, 1985, 2000 (mmt/y) Electric Export Subbasin Generation Gasification Sync rude Fertilizer Rail Slurry Total Total 1980 Tongue 0 0 0 0 30.8 0 30.8 30.8 Mid-Yellowstone 4.0 0 0 0 24.0 0 24.0 28.0 Powder 0 0 0 0 6.9 0 6.9 6.9 Bighorn 0 0 0 0 6.9 0 6.9 6.9 TOTAL 4.0 0 0 0 68.6 0 68.6 72.6 1985 I Tongue 0 0 0 0 69.5 0 69.5 69.5 N -'==' Mid-Yellowstone 8.0 0 0 0 54.1 0 54.1 62.1 I Powder 0 0 0 0 15.5 0 15.5 15.5 Bighorn 0 0 0 0 15.5 0 15.5 15.5 TOTAL 8.0 0 0 0 154.6 0 154.6 162.6 2000 Tongue 8.0 0 0 0 105.6 26.4 132.0 140.0 Mid-Yellowstone 12.0 7.6 0 0 73.3 20.5 102.6 122.2 Powder 4.0 0 0 0 23.4 5.9 29.3 33.3 Bighorn 0 0 0 0 23.4 5.9 29.3 29.3 TOTAL 24.0 7.6 0 0 225.7 58.7 293.2 324.8 Table 11. Coal production for consumption under high-level development, Yellowstone Basin (mmt) 1971 1975 Consuming Sector (Actual) (Actual) 1980 1985 2000 Household and Commercial 0.1 0.2 insig. insig. insig. Industrial 0.1 0.2 insig. insig. insig. Electrical Generation 0.8 0.8 4.0 8.0 32.0 Synthetic Fuel gas 0 0 0 0 22.8 crude 0 0 0 0 36.0 fertilizer 0 0 0 0 3.5 Exports 6.1 21.0 71.4 199.1 368.5 TOTAL 7.1 22.2 75.4 207.1 462.8 The 1980 projection of coal production for electrical generation shown in table 2 is based on· coal production data tabulated by the Montana Energy Advisory Council (1974). However, the coal export in 1980 is a combination of the adjusted NGPRP data and recent changes in coal sales contracts. The 1985 projection of coal production for electrical generation is 8.0 mmt, double the 1980 amount, because it was assumed that Colstrip Units 3 and 4 would be in operation by that date. The projection of coal production for export in 1985, 199.1 mmt, was derived from NGPRP projections and from a Missouri River Basin Commission (MRBC) study, Anal sis of Ener Pro·ections and Implications for Resource Requirements (1976 • High-level coal develop- ment estimates are based on assumptions that 20 percent of the coal in 1985 will be exported by slurry, increasing total export capacity to 199.1 mmt. This figure includes coal moving by unit train. Under high-level development projections for the year 2000, electrical generation would consume 32.0 mmt of coal. This figure is derived from the Western States Water Council's (1974) estimation of production of 8,260 mw of electricity from coal for 1990. The synthesis of fuel and fertilizer is estimated to require 61.3 mmt of coal by 2000 under high-level development. Approximately 23 mmt of the total would go toward synthesis of gas equivalent to the production of three plants, each with the capacity of 250 million standard cubic feet per day (mmcfd). The figure was derived from the NGPRP's high-development projection of demand for substitute natural gas and was modified by MUCDS's findings concerning the viability of coal gasification. Because success of technology for the economical production of synthetic liquid fuel from coal does not appear likely until the late 1990s, high- level development does not assume the construction of a liquefaction plant -25 - until the year 2000. Two such plants are projected. The Stanford Research Institute (1974) has estimated that one synthetic crude oil facility producing 100,000 barrels of crude per day would require 18 mmt of coal per year. That amount is more than twice the quantity that would be consumed by a synthetic natural gas plant of 250 mmcfd capacity. One fertilizer plant is projected for southeastern Montana by the year 2000 under high-level development. The present status of technology makes development possibilities slim. The Koppers' Totzek process seems to be the most feasible conversion process at this time and would require a maximum of 3.5 mmt of coal per year to produce 2,300 tons of fertilizer per day (t/d). The export of coal in the year 2000 under high-level development is projected to reach 368.5 mmt. This quantity was derived from the NGPRP's high-development projection plus a 40 percent increase to account for the use of slurry pipelines. Table 12 shows the location by subbasin of the coal-based electrical generation, synthetic gas, liquefaction, and fertilizer production plants forecast under the assumptions of high-level development. Table 13 shows coal production by subbasin during the remalnlng years of the century under high-level development. The production figures shown in table 11 appear in the basin-wide totals for each of the consumptive uses shown in the tables--electrical generation, gasification, production of synthetic crude oil and fertilizer--plus exports. Under th~ assumpticins of high-level coal development in the Yellowstone Basin, exports of coal by slurry pipeline would be 20 percent of coal exports by 1980 and 40 percent by 2000 (see export column, table 13). SUMMARY OF LEVELS OF DEVELOPMENT A gradual rise in coal production to 1980 at least is practically inevitable based on the demand for coal represented in existing coal sales contracts. Low-level development projections reflect the existing situation plus the added demand of planned coal-for-export sales contracts. (The pro- jected low-level demand for coal is similar to the intermediate coal development_profile of the Northern Great Plains Resource Program (1974b).) High-level development is a projection of coal production based on assumptions about U.S. energy use under a policy of national self-sufficiency and a reliance on coal rather than energy c~nservation, alternative energy sources, oil, natural gas, and nuclear power. (An implicit assumption is that the coal would be produced in western strip mines rather than eastern underground mines.) Under high-level development, coal production tonnages could reach the totals indicated in table 14. Intermediate-level development projections· represent means between the low and high levels of development. As far as we know, no one of the three development levels is more probable than the others. Figure 3 presents a graph of coal production in the Yellowstone River Basin for the three levels of development during the remaining years of the -26- Table 12. Location of coal conversion facilities through the high-level development year 2000, 1000-mw 100,000-b/d Electric 250-mmcf/d Synthetic 2300-t/d Generating Synthetic Crude Fertilizer Subbasin Plants Gas Plants Plants Plants 1980 Mid-Yellowstone 1 0 0 0 All others 0 0 0 0 TOTAL 1 0 0 0 1985 Mid-Yellowstone 2 0 0 0 All others 0 0 0 0 TOTAL 2 0 0 0 2000 Tongue 3 1 1 0 Mid-Yellowstone 3 2 1 0 Powder 1 0 0 0 Bighorn 1 0 0 0 Lower Yellowstone 0 0 0 1 TOTAL 8 3 2 1 -27- Table 13. Coal tonnage location by Yellowstone River subbasins, high-level development, 1980, 1985, 2000 (mmt/y) Electric Export Subbasin Generation Gasification Sync rude Fertilizer Rail Slurry Total Total 1980 Tongue 0 0 0 0 32.2 0 32.2 32.2 Mid-Yellowstone 4.0 0 0 0 25.0 0 25.0 29.0 Powder 0 0 0 0 7.1 0 7.1 7.1 Bighorn 0 0 0 0 7.1 0 7.1 7.1 Lower Yellowstone 0 0 0 0 0 0 0 0 TOTAL 4.0 0 0 0 71.4 0 71.4 75.4 1985 I Tongue 0 0 0 0 71.7 17.9 89.6 89.6 N (X) Mid-Yellowstone 8.0 0 0 0 55.8 13.9 69.7 77.7 Powder 0 0 0 0 15.9 4.0 19.9 19.9 Bighorn 0 0 0 0 15.9 4.0 19.9 19.9 Lower Yellowstone 0 0 0 0 0 0 0 0 TOTAL 8.0 0 0 0 159.3 39.8 199.1 207.1 2000 Tongue 12.0 7.6 18.0 0 99.5 66.3 165.8 203.4 Mid-Yellowstone 12.0 15.2 18.0 0 77.3 51.6 128.9 174.1 Powder 4.0 0 0 0 22.1 14.8 36.9 40.9 Bighorn 4.0 0 0 0 22.1 14.8 36.9 40.9 Lower Yellowstone 0 0 0 3.5 0 0 0 3.5 TOTAL 32.0 22.8 36.0 3.5 221.0 147.5 368.5 462.8 -~------------ Table 14. Coal production for consumption under three levels of development, Yellowstone River Basin, through the year 2000 (mmt/y) Consuming Low Intermediate High Sector Level Level Level 1971 (Actual) Household and Commercial 0.1 0.1 0.1 Industrial 0.1 0.1 0.1 Electrical Generation 0.8 0.8 0.8 Synthetic Fuel. 0 0 0 Exports 6.1 6.1 6.1 TOTAL 7.1 7.1 7.1 1975 (Actual) Household and Commercial 0.2 0.2 0.2 Industrial 0.2 0.2 0.2 Electrical Generation 0.8 0.8 0.8 Synthetic Fuel 0 0 0 Exports 21.0 21.0 21.0 TOTAL 22.2 22.2 22.2 1980 Household and Commercial insig. insig. insig. Industrial insig. insig. insig. Electrical Generation 4.0 4.0 4.0 Synthetic Fuel 0 0 0 Exports 66.0 68.6 71.4 TOTAL 70.0 72.6 75.4 1985 Household and Commercial insig. insig. insig. Industrial insig. insig. insig. Electrical Generation 4.0 8.0 8.0 Synthetic Fuel 0 0 0 Exports 114.0 154.6 199.1 TOTAL 118.0 162.6 207.1 2000 Household and Commercial insig. insig. insig. Industrial insig. insig. insig. Electrical Generation 8.0 24.0 32.0 Synthetic Fuel Gas 7.6 7.6 22.8 Crude 0 0 36.0 Fertilizer 0 0 3.5 Exports 171.1 293.2 368.5 TOTAL 186.7 324.8 462.8 -29- 400 350 300 250 en c: 0 1--... 200 0 ..c. (/) c: 0 ~ 150 100 50 1971 1975 1980 1985 Years 1990 1995 Figure 3. Base, low, intermediate and high alternative futures for coal production in the Yellowstone River Basin. -30- 2000 century. It is obvious from the graph that the year 1980 will be a signifi- cant turning point for questions of public policy associated with coal devel- opment. Until 1980, under all three development assumptions, only the Mid- Yellowstone Subbasin would have energy conversion facilities--the equivalent of one 1,000-mw power plant. By 1985, under intermediate or high-level development, the Mid-Yellowstone would have two 1,000-mw power plants. Table 15 illustrates the situation by the end of the century. With low-level development, there would be a total of 2000 mw of electrical generation in the Mid-Yellowstone and Tongue Subbasins, and there would be one 250-mmcf/d synthetic gas plant in the Mid-Yellowstone. With intermediate- level development, there would be 6,000 mw of electrical generation facilities: half of it in the Mid-Yellowstone, 2,000 mw in the Tongue, and 1,000 mw in the Powder. The Mid-Yellowstone would have one synthetic gas plant. With high-level development, the addition of a 1,000-mw power plant in the Bighorn Subbasin would bring to four the total of subbasins with energy conversion plants. The Tongue Subbasin would have yet another power plant under high-level development, for a basin total of 3,000 mw, and would contain a 250-mmcf/d synthetic gas plant and a 100,000-b/d synthetic crude oil plant as well. The Mid-Yellowstone Subbasin would have one synthetic crude oil plant and two synthetic gas plants in addition to its power plants. The Lower Yellowstone Subbasin also would enter the picture with a 2,300-t/d fertilizer plant. Four subbasins would remain unaffected by direct impacts of energy facilities under high-level development even in the year 2000; Upper Yellowstone, Billings Area, Clarks Fork Yellowstone, and Kinsey Area. WATER USE ASSOCIATED WITH PROJECTED ENERGY DEVELOPMENT . Annual water and coal consumption requirements for the conversion plants envisioned have been calculated (see table 16). Using the water- use information in table 16 and information on the expected numbers of energy conversion .facilities in each subbasin, a comprehensive picture of water use by subbasin for the years 1980, 1985, and 2000 is presented in tables 17, 18, and 19. The basin-wide totals for all uses in 1980, 1985, and 2000 are 18,770, 61,995, and 321,175 af/y, respectively, under high- level development. -31- Table 15. Coal Conversion in the Yellowstone Basin in 2000 Electric Generation SNG Sync rude Fertilizer Subbasin a (mw) (mmcf /d) (b/d) (t/d) LOW-LEVEL DEVELOPMENT Bighorn 0 0 0 0 Mid-Yellowstone 1,500 250 0 0 Tongue 500 0 0 0 Powder 0 0 0 0 Lower Yellowstone 0 0 0 0 TOTAL 2,000 250 0 0 INTERMEDIATE-LEVEL DEVELOPMENT Bighorn 0 0 0 0 Mid-Yellowstone 3,000 250 0 0 Tongue 2,000 0 0 0 Powder 1,000 0 0 0 Lower Yellowstone 0 0 0 0 TOTAL 6,000 250 0 0 HIGH-LEVEL DEVELOPMENT Bighorn 1,000 0 0 0 Mid-Yellowstone 3,000 500 100,000 0 Tongue 3,000 250 100,000 0 Powder 1,000 0 0 0 Lower Yellowstone 0 0 0 2,300 TOTAL 8,000 750 200,000 2,300 aThe four subbasins not listed (Upper Yellowstone, Billings Area, Clarks Fork Yellowstone, and Kinsey Area) are not expected to include sites for coal conversion facilities. -32- Table 16. Annual water and coal requirements for coal processes Process Water Thermal-electric generation 15,000 af/y/1,000 mw Gasification 9,000 af/y/250 mmcf/d Syncrude 29,000 af/y/100,000 b/d Fertilizer 13,000 af/y/2,300 t/d Slurry Strip Mining 750 af/mmt 50 af/mmt -33- Coal 4 mmt/1,000 mw 7.6 mmt/250 mmcf/d 18 mmt/100,000 b/d 3.5 mmt/2,300 t/d Table 17. Water use in coal mining and electrical generation by 1980 by subbasin (af/y) Subbasin a Tongue Mid-Yellowstone Powder Bighorn TOTAL Tongue Mid-Yellowstone Powder Bighorn TOTAL Tongue Mid-Yellowstone Powder Bighorn TOTAL Elec. Generation LOW-LEVEL DEVELOPMENT 0 15,000 0 0 15,000 Strip Mining 1,490 1,360 330 330 3,510 INTERMEDIATE-LEVEL DEVELOPMENT 0 1,540 15,000 1,400 0 350 0 350 15,000 3,640 HIGH-LEVEL DEVELOPMENT 0 1,610 15,000 1,450 0 360 0 360 15,000 3,780 Total 1,490 16,360 330 330 18,510 1,540 16,400 350 350 18,640 1,610 16,450 360 360 18,780 aFour subbasins (Upper Yellowstone, Billings Area, Clarks Fork Yellowstone, and Kinsey Area) are not expected to experience water depletion associated with coal development. The Lower Yellowstone Subbasin would be subject to coal development only by the year 2000. -34- Table 18. Water use in coal mining, transportation and conversion processes by 1985 by subbasin (af/y) Subbasin a Elec. Total Generation Slurr~ Export Strip Mining Tongue Mid-Yellowstone Powder Bighorn TOTAL 0 15,000 0 0 15,000 LOW-LEVEL DEVELOPMENT 0 0 0 0 0 2,570 2,200 570 570 5,910 2,570 17,200 570 570 20,910 INTERMEDIATE-LEVEL DEVELOPMENT Tongue 0 0 3,480 3,480 Mid-Yellowstone 30,000 0 3,ll0 33 'llO Powder 0 0 780 780 Bighorn 0 0 780 780 TOTAL 30,000 0 8,150 38,150 HIGH-LEVEL DEVELOPMENT Tongue 0 6, 720 4,480 11 '200 Mid-Yellowstone 30,000 10,430 3,890 44,310 Powder 0 1,500 1,000 2,500 Bighorn 0 3,000 1,000 4,000 TOTAL 30,000 21,650 10,370 62,010 aThe four subbasins not shown (Upper Yellowstone, Billings Area, Clarks Fork Yellowstone and Kinsey Area) are not expected to experience water depletion associa- tion with coal development. The Lower Yellowstone Subbasin would be subject to coal development only by the year 2000. bit is assumed that half of the water for slurry in the Tongue and Powder subbasins will be from deep ground water, and half fromsurface water. In the Mid-Yellowstone and Bighorn subbasins, all water for slurry is assumed to come from surface supplies. -35- Table 19. Water use in coal m1n1ng, transportation and conversion processes by 2000 by subbasin (af/y) INCREASE IN DEPLETION Elec. Gasi fi-Syn-Ferti-Slurryb Strip Subbasin a Generation cation crude lizer Export Mining Total LOW-LEVEL DEVELOPMENT Bighorn 0 0 0 0 0 B60 860 Mid-Yellowstone 22,500 9,000 0 0 0 3,680 35,180 Tongue 7,500 0 0 0 0 3,950 ll ,450 Powder 0 0 0 0 0 860 860 Lower Yeilowstone 0 0 0 0 0 0 0 Total 30,000 9,000 9,350 48,350 INTERMEDIATE-LEVEL DEVELOPMENT Bighorn 0 0 0 0 4,420 1,470 5,890 Mid-Yellows tone 45,000 9,000 0 0 15,380 6,110 75,490 Tongue 30,000 0 0 0 9,900 7,000 46,900 Powder 15,000 0 0 0 2,210 1,670 18,880 Lower Yellowstone 0 0 0 0 0 0 0 Total 90,000 9,000 31,910 16,250 147,160 HIGH-LEVEL DEVELOPMENT Bighorn 15,000 0 0 0 ll ,100 2,050 28 '150 Mid-Yellowstone 45,000 18,000 29,000 0 38,700 8,710 139,410 Tongue 45,000 9,000 29,000 0 24,860 10,170 ll8 ,030 Powder 15,000 0 0 0 5,550 2,050 22,600 Lower Yellowstone 0 0 0 13,000 0 0 13,000 Total 120,000 27,000 58,000 13,000 80,210 22,980 321,190 aThe four subbasins not shown (Upper Yellowstone, Billings Area, Clarks Fork Yellowstone, and Kinsey Area), are not expected to experience water depletion associated with coal development. bit is assumed that half of the water from slurry in the Tongue and Powder subbasins will be from deep ground water and half from surface water. In the Mid-. Yellowstone and Bighorn subbasins, all water for slurry is assumed to come from surface supplies. -36- The use of irrigated agriculture in the Yellowstone Basin has been increasing for the past few years, possibly reversing (at least temporarily) a long-term downward trend. Forecasting the extent of further expansion of irrigated agriculture to the year 2000 is complicated. General economic conditions, federal import and export policies, and world eating habits greatly affect crop prices. Many agricultural products grown in the basin through irrigation methods are used for the production of beef, which has a highly variable market. Farmer preferences and peer influences are significant.but unpredictable in determining whether a farmer will decide to expand irrigation. Finally, adequate land and an accessible water supply are necessary. This study considers water and land availability and economic constraints in projecting the amount of irrigation in the Yellowstone Basin through the year 2000. Previous studies of irrigated agriculture illustrate a range of approaches to these problems. Some of these studies forecast future develop- ment, and others analyze specific projects or geographical areas for , irrigation feasibility. The OBERS Series C projections (U.S. Water Resources Council 1972) were based on estimates of anticipated supply and demand and historical trends. However, because irrigated agri~ulture has been declining until recently, the OBERS study predicted only small increases in Montana's irrigated acreage to meet anticipated national demand in the year 2020. It became obvious that OBERS study predictions were wrong when the projections for 2020 were surpassed in 1974. So DNRC developed new pro- jections based on the OBERS red meat projections (Montana DNRC 1976). Neither of these studies considered the availability of suitable land or the economic limitations of irrigated agriculture. The study reported here takes these factors into account. The Bureau of Reclamation (USSR 1955, 1959, 1963, 1971, 1972) has conducted irrigation studies in several areas of the Yellowstone Basin. Information is available for the Powder, Tongue, and Bighorn rivers, and for several projects along the mainstem of the Yellowstone. The economic analysis of these projects was updated for the Yellowstone Level 8 Study. A single-purpose irrigation study used in its original form (Frederiksen 1976) analyzed additional projects for inclusion in the Level 8 Study. Both of these studies considered large projects only and either explicitly ar implicitly assumed_there would be a cooperative effort to build and operate them. However, recent irrigation development in the basin has occurred primarily through private development with little or no cooperation among farmers to coordinate the installation of water-delivery systems; therefore, this study analyzes irrigation development in the Yellowstone Basin by postulating a collection of individual developments rather than cooperative projects. -37- t~ETHODS The objective of this study is to provide agricultural water-demand projections for a hydrologic model of the Yellowstone River Basin. Data were gathered and analyzed to provide general information on water demand, rather than identification of any specific development project. Three classes of information were used to identify potential water demand: 1) identi- fication of irrigable land, 2) calculation of irrigation costs, and 3) analysis of the ability to pay these costs based on farm budgets. IDENTIFICATION OF IRRIGABLE LAND By systematically appraising soil, relief, and climate, parcels of land may be classified based on their suitability for irrigation. Land classification surveys made by the Water Resources Division, DNRC, were designed to investigate the theoretical potential of the land in the Yellow- stone Basin to sustain irrigated farming. The term "irrigable land," as used here, denotes land with soils, topography, and drainage features appropriate for irrigation by either ,gravity or sprinkler methods. Such land is divided into classes on the basis of its relative potential for irrigated farming. Class 1 irrigable land has potentially high productive value; class 2 ~irrigable land has intermediate value, and class 3 irrigable land has the lowest suitability for irrigation among the classes. To perform the classification process for the Yellowstone River Basin, broad assumptions were necessary in areas where little soil information was available; conse- quently, this survey should not be considered adequate for detailed plans. Table 20 lists the classification criteria. The land classification survey identified 2,200,000 acres of irrigable land in the basin. However, the survey considered neither water availability no.r economic limitations of potential irrigation systems. For this study, water was considered to be available only from the Yellowstone River and its four main tributaries in Montana (Clarks Fork, Bighorn, Tongue, and Powder). Preliminary economic limitations were defined by using calculations from first drafts of the farm-budgets and water- delivery analyses. Th~se preliminary calculations helped define potentially irrigable land as that no more than 3 mi from the river and no more than 450 ft above the river. Hence the total of potentially irrigable land was reduced to 440,000 acres. That land was divided into categories according to lift (50-ft increments), and pipeline length (~-mi increments) for each subbasin (table 21). Irrigation costs were calculated for each category. CALCULATION OF IRRIGATION COSTS In this study irrigation costs were divided into water-delivery costs and water-application costs. Water-delivery cost was defined as the total cost of pumping water from the river to the point of application. Water-application cost was defined as the cost of owning and operating a center-pivot sprinkler system. -38- J ·I .I 'I I .:1 I Table 20. Land classification specifications Soil or Land Characteristics l. Dominant texture of root zone 2. Depth to clean sand, gravel and cobble 3. Hard rock, sandstoBe or nonsaline shale 4. Textural 11odi fiers c a. Volume of tillage layer: Gravel ( -3 in) Cobble (3-10 in) b. Stoniness of surfaced and tillage layer, stones generally greater than 12 in in diameter c. Rockiness (small out- crops within soil type) 5. Available waterholding capacity (to a maximum depth of 4 ft) 6. Permeability 7. Salinity and/or alkalinitye 8. Slope 9. \;ater table drainage 10. Drainage overflo1• 11. Climate Class 1 - Only Slight Limitationsa Fine sandy loam to friable clay loam 40 in minimum 60 in minimum No tillage problem 15 percent No tillage problem No tillage problem Less than 2 percent of bedrock exposed. l·lore than 6 in l·loderately slow--.20 in/ hr to moderate--2.00 in/hr, may exceed 2 in if suffici- ent water holding capacity is maintained--by field observation of soil texture and structure Electrical conductivity not to exceed 4 millimhos/cm;may be higher under good leach- ing and drainage conditions. Sut not to exceed 8 millim- hos/cm in top 4 ft 0 to 4 percent Easily maintained below 5 ft depth during growing season :llo overflow Growing season greater than 90 days SOURCE: l-lontana DNRC (unpublished). CONVERSIONS: ft in 30.4 em 2. 54 em Class 2 - l·loderate Limitationsa Loamy sand to permeable clay 20 in minimum 40 in minimum l·loderate tillage problem 15-50 percent -~ in 15 percent (3-10 in) Cultivation not impractical. Stones 12 in diameter occupy 0.01 to 0.1 percent of the surface, and 0.15 to 1.5 cubic yards/acre-foot 2 percent of surface may have bedrock exposed. l·lore than 4 in Slow--.06 in/hr to moderately rapid--2.00 to 6.30 in/hr-- by field observation of soil texture and str11cturc. Electrical conductivity not to exceed 8 millimhos/cm; except under good leaching and drainage conditions. Host horizons will have less than 8 millimhos/cm. Less than 8 percent Practical to maintain below 40 in de-pth most of the time in growing season (requires drainage) Free of overflow in grm•ing season Growing season greater than 90 days Class 3 - Severe Limitations" Loamy sand to clay (sands with su ffic.i ent 1'/IIC. can be included) 10 in minimum 30 in minimum Severe tillage problem -50 percent -3 in 15-50 percent 3-10 in Cultivation impractical unless cleared. Stones 12 in diameter; occupy 0.1 to 3 percent of the surface, and 1.5 to 50 cubic yds/acrc-fool. 2 to 10 percent surface may have bedrock exposed. l·lore than 2 in Very slow--less lhan .06 in/hr only in thin layers. To rapid--greater than 6.30 in/hr if upper 4 ft. of soil has sufficient water holding capacity--by field observation of soil texture and structure. Electrical conductivity not to exceed 0 millimhos/ em in top 2 ft. Lower l1orizons may l1e hiqher under good leaching and drainage conditions, but not to exceed 15 millimhos/cm. 15 percent (sprinkler irri- 4ation on slopes more than 8 percent) Can maintain below 20 in most of the growing season. Ovnrflow may be hazard to crops in 2 or 3 of 10 yrs Growing season may be less than 90 days aAny one deficiency below the limits of a class is cause for downgrading to next lower class. h10 or more such deficiencies may cause downgrading two classes if judgment indicates they arc additive. Combinations of less-severe deficiencies may or may not effect a change in ·class. bSoils known to be underlain by saline shale at depths as shallow as 60 in are excluded from Closs l through 3. cln areas where the planned agricultural use is of demonstrated suitability, any modifier can he rated irrignhle for special uses not requiring tillage. dFor detailed description see USDA, 1951 Soil Survey 1-innual, pp. 217 'lnd 220. eSlight or moderate salinity or alkalinity may exclude soils from Classes 1 through 3 if associated with a slow-permeable substratum, or saline shale, or both. If leaching is not practical, u soil may be excluded from irriguhle clAss if ex- changeable sodium is greater than 3.0 millequivalents per 100 grams and/or if sodium absorption ratio is greater than 12 millequivalcnts per 100 grams, in any so.il with cation-exchange capacity less than 25 millequivalento per 100 grams. -39- Table 21. Irrigable acreage by lift (fl), pipeline length (mi) and subbasin in Yellowstone River Basin Lift Pipe length 50 100 150 200 250 300 )50 400 450 Total UPPER YELLOWSTONE SUBBASIN .5 JB,076 1,014 39,090 1.0 1,404 3,962 1,601 6,967 1.5 670 1,235 J, 252 l,OB7 6,244 2.0 2,391 1,533 2,649 3,613 10 ,1B6 2.5 0 3.0 0 Total JB,076 5,479 1,235 3,252 0 5,495 0 4,250 4,700 62,4B7 CLARKS FORK YELLmiSTONE SUBBASIN .5 2,160 392 766 442 3, 760 1.0 203 203 1.5 4'i6 3,432 2,157 6,025 2.0 1,006 1,006 2.5 3 '715 J. 715 3.0 B91 B91 Total 2,160 595 1,442 766 3. 715 4,765 0 2,157 0 15,600 BILLINGS AREA SUB BAS IN .5 3 ,JOB J ,324 329 2,147 222 9,330 1.0 347 71 B,OB4 1,305 1,254 447 11,50B 1.5 110 3, 549 5B5 442 B7B 5,564 2.0 165 99B 27B 2,325 3,766 2.5 446 446 3.0 11B 662 780 Total 3,765 3,67B 11,962 4,037 1,440 2,354 27B 3,21B 662 Jl, 394 BIGHORN SUBOASIN .5 4,47B 1,309 5, 7B7 1.0 1,60B 3,451 949 1,054 7,062 1.5 2,191 2,191 2.0 1 ,431 7BJ JB4 2. 59B 2.5 l,JB7 5Bl 1,96B 3.0 3,734 1,159 4,B93 Total 6,U~6 I ,Vl~ ~,UU4 L,~~6 u J~4 u u u l4,49~ I~ID-YELLOI1STONE SUBBASIN .5 16,000 1,691 17,691 1.0 3,180 4 ,J5B 4,616 2,B02 297 15' 253 1.5 4,004 2,270 4,522 309 2,071 13,176 2.0 B20 257 2,693 6,6Bl ),353 1,149 14,953 2.5 42B 3,534 4 ,B51 B,B13 3.0 1 979 2 459 1 5JB 5 976 lola! 20,000 l0,7JB 9,2BB D,2B7 B,l72 B,76B J,609 0 0 75,B62 KINSEY AREA SUBBASIN • 5 J,24B l,lBO 4,42B 1.0 539 539 1.5 JOB 2,035 731 3,074 2.0 464 546 1,405 2,415 2.5 0 J.O 0 Total 3,556 2,499 549 l,lBO 0 1,277 1,405 0 0 10,456 TONGUE SUBBASIN .5 21,947 0 21,947 1.0 0 1.5 9BJ 1,004 1,9B7 2.0 0 2.5 529 529 3.0 0 Total 21,947 0 0 9BJ 1,004 529 0 0 24,463 POWDER SUBBASIN • 5 74.224 74,224 1.0 9Bl 9Bl 1.5 993 1,2BB 2,2Bl 2.0 2,612 2,612 2.5 6,B72 6,B72 J.O 904 27 040 27 944 Total 75.205 0 0 u 995 J,900 I, 776 Ll ,040 0 114,914 l011ER YELlOWSTONE SUBBASIN .5 23,677 l,B04 1, 775 27,256 1.0 .l,B13 4,992 4,BB7 11 ,692 1.5 2. 599 792 JB6 12,JB9 16,166 2.0 805 4,B07 2,120 1,603 564 537 290 10.726 2.5 350 5,101 5,451 ).0 96) 355 1 )41 6 56) 9 222 Total 25,490 11,163 7,374 3,211 1,603 564 l,B7B 29.230 0 00.513 -40- Water Delivery Costs The cost of deliveri~g water to the farm depends on the lift, distance, and amount of water delivered. Because of the large size of the study area and limitations of data, plans could not be tailored fa~ individual farm sizes, irrigation layouts, and soils data. Therefore, several assumptions and generalizations were made. A hypothetical 320 acre farm was used as the basis for all calculations. Water would be diverted at the rate of 1 cfs/50 acres (6.4 cfs/farm). Crop water requirements were set at 2.84 acre-feet/acre, including a 65 percent irrigation efficiency factor (USDA 1974). Therefore, the annual water re- quirement for the 320-acre farm would be 908 acre-feet. We assumed that the pumps would be electric and would require 1,717 hours of operation per year. The cost of electricity was assumed to be $.01/kWh. Using the foregoing assumptions, a computer program was used to calculate the annual cost of delivering water to the farm. All equations and cost factors were provided by the U.S. Bureau of Reclamation (USBR), and were updated to January 1976 prices. The initial investment for vertical pumps was determined from the equation: c = (QI)(6.10TDH + 600) where: c = cost of pumps ($) Q = flow rate (6.4 cfs) I = Cost index factor (2.09) TDH = Total dynamic head Total dynamic head equals static lift plus friction loss. Static lift was divided into 50-ft increments from 50 to 450 ft, and friction loss was computed using the Chezy-Manning formula with a roughness coefficient of n = 0.010. where: v = velocity (6.4cfs/area of pipe) n = Mannings coefficient (0.010) L = pipe length R = hydraulic raidus (pire diameter/4) The total investment in pumps, housing, electrical panels, and installa- tion was assumed to be four times the cost of the pumps (USBR cost analyses). The initial cost of the pipe was provided by the USBR (tables 22 and 23), and excavation costs were determined from the equation: -41- Excavation cost = 3 WDL/27 where: W = width (twice the pipe diameter in ft) D = depth (6 ft plus pipe diameter) L = pipe length Annual investment costs were obtained by amortizing the initial invest- ment of pumps and pipe over 10 years at 10% interest, using a capital re- covery factor of 0.16275. Annual operation costs were calculated from the equation: Operation cost= (1.8Q"47 )(TDH)"46 (T/168)"34 (1.2W +I ) c w where: Q = flow rate (6.4 cfs) TDH = total dynamic head T = operation time (1,717 hours) W = workers wages ($5.83/hour) c I = costs index factor (1.87) c Maintenance costs were calculated .from the equation: Maintenance cost = (2Q·11 )(TDH)"41 (af)"43 (0.49W + I ) c w where: Q = flow rate (6.4 cfs) TDH = total dynamic head af = water pumped (908 acre-feet/year) W = workers wages ($5.83/hour) c I = cost index (1.87) w Finally, electricity costs were calculated from the equation: C = (UQT)(TDH)/8.8E where: U = electricity cost/k~vh ($.01/k~~h) Q = flow rate (6.4 cfs) T = time of operation (1,717 hours) TDH = total dynamic head E = pump efficiency factor (.7) -42- The total annual costs of operation, maintenance, and electricity were added to the amortized cost of the pumps and pipe. All calculations were repeated for each pipe size, and the most economical system was selected. ·Water delivery costs were then calculated for each lift and dis- tance category, and are displayed in table 24. Table 22. Concrete pipe costs ( $/ft) Diameter (in) Head (ft) 12 18 24 30 50 8.94 14.72 21.26 28.34 100 9.27 15.26 22.89 30.52 150 9.59 16.35 23.98 32.70 200 10.79 18.53 27.25 37.06 Table 23. Steel pipe costs ($/ft) Diameter (in) Head ( ft) 12 18 24 30 36 42 48 50 10.90 21.80 32.70 43.60 57.77 70.85 87.20 100 14.17 25.07 35.97 46.87 61.04 78.48 93.74 150 18.53 29.43 40.33 51.23 65.40 81.75 102.46 200 25.07 35.97 46.87 57.77 80.66 100.28 123.17 300 38.15 49.05 59.95 70.85 91.56 112.27 143.88 350 45.78 56.68 67.58 78.48 99.19 118.81 154.78 400 49.05 59.95 70.85 81.75 102.46 134.07 164.59 450 56.68 67.58 78.48 89.38 110.01 143.88 176.58 -43- Table 24. Annual water-delivery costs ($/acre) Elevation Length (mi) 50 100 150 200 250 300 350 400 0.5 55 68 79 105 116 136 147 167 1.0 79 93 133 144 168 184 207 223 1.5 103 117 172 202 213 250 261 299 2.0 128 142 212 247 258 304 315 362 2.5 152 167 251 292 303 358 369 424 3.0 176 192 291 337 348 412 423 487 a Steel pipe is unsuitable for these pressures. Water Application Costs Water application costs were derived from information provided by Montana State University (Montana State University 1969). - 450 178 247 310 373 a a Table 25 itemizes the cost of owning and operating one center-pivot sprinkler system. Changes that were made in the CES data to make the costs compatible with farm budget estimates are included under the column labeled NOTES. The initial cost of all equipment was amortized over 10 years at 10 percent interest (Capitol Recovery Factor = 0.16275) and added to the annual operating costs. The data then were indexed to December 1975 prices (Water Resources Council unpublished) to yield an annual cost of $66/acre. Initial investment Annual payment ~1aintenance Electricity Labor Taxes Insurance TOTAL per acre Table 25. Center-pivot irrigation costs Costs $48,022 7,816 158 652 175 768 288 9,857 66 -44- Notes 10% over 10 years 0.33% of investment 65,180 kWh/yr ® 1 mill/kWh $2.50/hr, 70 hrs/yr 160 mills on 10% of investment .6% of investment 148 irrigated acres FARM BUDGETS AND THE ABILITY TO PAY FOR IRRIGATION The potential for expanding irrigated land, of course, depends heavily on returns that can be expected on the investment. For each subbasin,farm budgets were prepared reflecting local cropping patterns. The budgets in- cluded the specific costs and returns associated with irrigated-crop pro- duction, plus generalized farm costs such as investment, maintenance, and repair of buildings and fences. Because the budgets included all costs associated with an irrigated farm (except water delivery and application). including payments to th~ fa~mer for his labor, management, and investment, profit after sale of the irrigated crops was assumed to he available to pay for irrigation. Historical records (Montana Department of Agricultura 1946-74) were used to develop cropping patterns for each subbasin. All crops produced in each area were placed into one of four categories. Sugar beets represented all high-value cash crops such as beets or dry beans. Barley represented the grain crops, alfalfa represented all hay, and corn silage represented silage crops including ~nsiled hay and beet tops. All calculations were based on the hypothetical 320-acre farm because data were readily available from the USBR for that siz~ of operation. The farmstead, roads, ditrhes, and wasteland accounted for 18 acres (5.6 percent); the remaining 302 acres were assumed to be available for crop production. Far convenience, costs and revenues were divided into four categories: fixed costs, variable costs, revenues, and perquisites. Fixed Costs Fixed costs included those incurred regardle~s of the acreage planted to a particular crop. Depreciation, repair, taxes, and investment are all fixed co~ts; they are listed in table 26. Depreciation was calculated on all buildings, machinery~and equipment using a 6.5 percent sinking fund factor over the expected life of the item. Repair costs were assumed to be 2 percent of the value of buildings and improvements, and 2.5 percent on machinery and equipment. A 7.1 percent return was calculated on all investments. Taxes were assumed to be levied against 30 percent of the assessed value on land and buildings and 20 percent on machinery and equipment. The assess- ed value of an acre of irrigated land was assumed to be $48.00. Buildings and improvements were assumed to be assessed at 40 percent, and machinery and equipment at 50 percent of their average values. The mill levy in the Yellowstone Basin was assumed to average 160 mills. Depreciation and repair costs for automobiles and trucks, based on mileage estimates, are shown in table 27. Fixed costs for insurance, telephone, and electricity also are included in table 27. -45- Table 26. Inventory of buildings, machinery and equipment; investment, repair, depreciation, and taxes for a hypothetical 320-acre farm t~arket Annual Annual Expected Annual Annual Item Value Investment Repairs Life (yrs) Depreciation Tax Land $ 80,000 $ 5,680 $ 737 House 22,200 1,576 $444 50 $65 426 Garage 2,200 158 44 40 13 42 Granary 1,665 ll8 33 20 43 32 Shop 1,665 ll8 33 20 43 32 Fuel Tanks 444 32 9 20 12 9 Well 888 63 18 30 10 17 Plow 1,332 95 33 12 77 21 Disk . 1,554 llO 39 15 64 25 Harrow 355 25 7 20 9 6 Sugar Beet 7,082 503 177 12 408 ll3 Equip. Drill 1,554 llO 39 20 40 25 Planter 1,787 127 45 15 74 26 Cultivator 1,415 100 35 12 81 23 Loader 1,132 80 28 12 65 18 Wagon 666 47 17 15 28 11 Sprayer 710 50 18 15 29 11 Baler 3,885 276 97 10 288 62 \Hndrow 3,996 284 100 10 296 64 Auger 699 50 17 15 29 11 Small tools 311 22 8 5 55 5 Trucks 9,435 670 a a a 151 Auto 3,885 276 a a a 62 Tractors 7,215 512 b b b 115 TOTAL $ll,082 $1,241 $1,729 $2,047 ~Depreciation and repair costs are computed in table 27. Depreciation and repair costs are computed in table 29. -46- Table 27. Miscellaneous fixed costs for a hypothetical 320-acre farm Item Amount Used Rate Cost ($) DEPRECIATION & REPAIR Auto Truck (~ T) Truck ( 2 T) INSURANCE Buildings Vehicles TELEPHONE ELECTRICITY TOTAL Perquisites 4,000 mi 5,000 mi 3,500 mi $32,634 $ .14/mi $ .14/mi $ .28/mi $10.80/$1,000 560 700 980 352 165 90 210 $3,057 Farmers receive certain benefits (perquisites) living on the farm. A nonfarm person usually pays the cost of owning and maintaining a house, but on a farm such items are part of the economic enterprise. The farmer--not the farm enterprise--theoretically reaps the benefit from the farm's invest- ment in them. Table 28 lists these farm perquisites. Technically, perquisites are items of revenue not available for capital investment; as such, they are subtracted from fixed costs. Table 28. Farm perquisites (house, garage, well) Item Perquisite value ($) Depreciation 88 Investment 1,797 Repairs 506 Taxes 486 Insurance 273 TOTAL $3,150 -47- / Table 29. Variable costs per irrigated acre by crop Amount Cost/Unit Total Cost Item Used ($) ($) SUGAR BEETS Fertilizer: N. 100.8 lbs 0.22 22.18 P205 43.3. lbs 0.16 6.93 2 Labor: Family 8.4 hrs 2.25 18.90 Hired 11.7 hrs 2.50 29.25 Tractor 7.1 hrs 2.78 19.74 Seed 2.5 hrs 2.78 6.95 Custom Harvest 23.31 23.31 Ensiled Tops 10.5 tons 1.30 13.65 TOTAL 140.91 CORN SILAGE Fertilizer: N2 110.4 lbs 0.22 24.29 P205 59.0 lbs 0.16 9.44 Labor: Family 6.0 hrs 2.25 13.50 Hired 4.1 hrs 2.50 10.25 Tractor 3.4 hrs 2. 78 9.45 Seed 0.5 bu 25.00 12.50 Silage Storage 21 tons 1.30 27.30 TOTAL 106.73 ALFALFA Fertilizer: N2 0 P205 48.0 lbs 0.16 7.68 Labor: Family 5.4 hrs 2.25 12.15 Hired 2.8 hrs 2.50 7.00 Tractor 4.1 hrs 2.78 11.40 Seed 3.0 lbs 1.86 5.58 Twine 5 tons hay 0.61 3.05 TOTAL 46.86 BARLEY Fertilizer: N2 65.4 lbs 0.22 14.39 P205 38.1 lbs 0.16 6.09 Labor: Family 3.2 hrs 2.25 7.20 Hired 0 Tractor 2.0 hrs 2.78 5.56 Seed 2.0 bu 3.70 7.40 Weed Spray 1.15 1.15 Custom Combine 7.70 7.70 TOTAL 49.49 -48- Variable Costs In addition to the fixed costs associated with the farm enterprise,many costs, such as fertilizer, seed, labor, and tractor use, vary with the crop type and acreage grown. Table 29 lists these variable costs per acre for a hypothetical farm. All costs were tailored to a specific crop and an anticipated yield under irrigation. Fertilizer use was based on the amount needed to produce the expected yield. Tractor costs were included as variable costs primarily because of the format of available data. Revenues Table 30 lists irrigated-crop production and sales per acre. Expected yields assume better-than-average management skills and reflect amounts of labor, fertilizer, and chemical sprays used to ensure good crop growth. Sales prices were based on Water Resources Council price standards (U.S. Water Resources Council 1975). Prices for silage (corn and beet tops) were based on Water Resources Council hay prices and adjusted to reflect nutrient content. Table 30. Irrigated-crop production and sales per acre Crop Yield Sales Price/Unit Total Revenue per acre Sugar Beets Beets 21 tons $34.97 $734 Tops 10.5 tons 18.73 197 CROP TOTAL 931 Corn Silage 21 tons 18.73 393 Al fa! fa 5 tons 44.59 223 Barley Grain 74 bushels 1.90 140 Straw 16 tons 2.68 43 CROP TOTAL 183 An allowance for the farmer's management skills was included in all budgets. This allowance amounted to 10 percent of·the net profit, and was calculated by reducing the absolute value of all costs and profits by 10 percent. Table 31 summarizes all costs and returns and calculates the management allowance. -49- Table 31. Farm budget summary with management allowance Management Net Item $Value Allowance ($) Value ($) Investment -ll '082 1,108 -9,974 Repairs -1,241 124 -1 'll7 Depreciation -1,729 173 -1,556 Taxes -2,047 205 -1,842 Miscellaneous -3,057 306 -2,751 Perquisites + 3,150 315 +2,835 Fixed Costs & Perquisites -14,405 Variable Costs (per acre) Sugar beets -141 14 -127 Corn Silage -107 ll -96 Alfa1 fa -47 5 -42 Barley -49 5 -44 Variable Returns (per acre) Sugar beets +931 93 +838 Corn Silage +393 39 +354 Alfalfa + 223 22 +201 Barley +183 18 +165 -50- Irrigation Feasibility The farm budgets prepared for each subbasin were based on cropping patterns listed in table 32. Variable costs and revenues were multiplied by the acres of each irrigated crop and combin~d with fixed costs of farming (except for the cost of water application systems) to obtain the figures shown in table 33. Then irrigation payment capacities were calculated per acre, and application-system costs (listed in table 25 as $66/acre) were subtracted from that amount to determine the landowner's capacity to pay for water-delivery systems (table 34). This per acre capacity to pay for pumping was compared with pumping costs per acre to determine the maximum pumping distance for each subbasin (table 35). Finally, the pumping distances were compared with the 440,000 acres of potentially irrigable land in the basin (table 21) to determine the total feasibly irrigable acreage. Table 36 displays the results in acres by subbasin--237,472 acres basin-wide; approximately 80 percent is within .5 mi of the water source and less than 50 feet above it. Table 32. Cropping patterns by subbasin, 320-acre farm Cropping Pattern (acres) Subbasin Farmstead Grain Hay Silage Cash Crop Upper Yellowstone 18 51 239 3 9 Clarks Fork 18 51 239 3 9 Billings Area 18 88 121 24 69 Bighorn 18 79 169 9 45 Mid-Yellowstone 18 73 178 9 42 Tongue 57 196 15 33 Kinsey Area 18 54 184 24 39 Powder 18 36 217 18 30 Lower Yellowstone 18 88 115 30 69 IRRIGATION AND WATER DEPLETION To allocate the 237,480 acres of feasibly irrigable acreage to the three development levels, we assumed that the low level of development would irrigate one-third of that figure, the intermediate level two-thirds, and the high level all 237,480 acres. Under assumptions of this study, annual irrigation-water requirements for the feasibly irrigable acreage in each subbasin would be constant at 906 af/farm, or 3.0 af/acre ~ssuming 3Q2 acres under irrigation. It is further assumed that one-third of the water withdrawn for application to crops eventually finds its way back to the rivers. Hence, net water depletion from irrigation development is assumed to be 2.0 af/acre. Development is assumed to rise steadily to completion in the year 2000. Low-level development of basin farmland--irrigating a total of one-third of the feasibly irrigable acreage in each subbasin--would deplete 158,000 af/y to water 79,160 acres (see table 37). -51- Intermediate-level development would irrigate a total of 158,310 acres and deplete the basin's water supply by over 316,000 af/y. High-level development would irrigate the entire 237,480 acres of feasibly irrigable land and cause depletion of nearly 475,000 af/y. -52- Table 33. Costs and returns by subbasin, 320-acre farm Variable Costs and Returns ($) Payment Cost($) Grain Hay Silaae Cash Crop Cap a- Subbasin Fixed Cost Return Cost Return Cost Return Cost Return city ($) Upper Yellowstone 14,405 2,224 8,415 10,038 48,039 288 1,062 1,143 7,542 36,960 Clarks Fork 14,405 2,224 8,415 10,038 48,039 288 1,062 1,143 7,542 36,960 Billings Area 14,405 3,872 14,520 5,082 24,321 2,304 8,496 8,763 57,822 70,733 Bighorn 14,405 3,476 13,035 7,098 33,969 864 3,186 5,715 37,710 56,342 Mid-Yellowstone 14,405 3,212 12,045 7,476 35,778 864 3,186 5,334 35,196 54,914 Tongue 14,405 2,508 9,405 8,232 39,396 1,440 5,310 4 ' 191 27 '6 54 50,989 Kinsey Area 14,405 2,376 8,910 7 '728 36,984 2,304 8,496 4,953 32,682 55,306 Powder 14,405 1,584 5,940 9,ll4 43,617 1 '728 6,372 3,810 25,140 50,428 Lower Yellowstone 14,405 3,872 14,520 4,830 23,115 2,880 10,620 8,763 57,822 71,327 Table 34. Payment capacity available for pumping (per acre) Irrigation Payment Capacity Payment Sprinkler for Basin Capacity Cost Pumping Upper Yellowstone $ 122 66 $ 56 Clarks Fork 122 66 56 Billings Area 234 66 168 Bighorn 187 66 121 t1id-Yellowstone 182 66 ll6 Tongue 2169 66 103 Kinsey Area 183 66 117 Powder 167 66 101 Lower Yellowstone 236 66 170 Table 35. ~1aximum pumping distance (mi) Subbasin Lift (ft) 50 100 150 200 250 300 350 400 Upper Yellowstone 0.5 Clarks Fork 0.5 Billings Area 2.5 2.5 1.0 1.0 1.0 0.5 0.5 0.5 Bighorn 1.5 1.5 0.5 0.5 0.5 Mid-Yellowstone 1.5 1.0 0.5 0.5 0.5 Tongue 1.5 1.0 0.5 Kinsey Area 1.5 1.0 0.5 0.5 0.5 Powder 1.0 1.0 0.5 Lower Yellowstone 2.5 2.5 1.0 1.0 1.0 0.5 0.5 0.5 -53- Table 36. Feasibly irrigable acreage by lift and pipeline length, high level of development (acres) Lift (ft) Pipeline length (mi) 0-50 50-100 100-150 150-200 200-250 250-300 Total UPPER YELLOWSTONE SUBBASIN 0 .5 38,076 0 0 0 0 0 38,075 CLARKS fORK SUBBASIN 0 • 5 2,160 0 0 0 0 0 2,160 BILLINGS AREA SUBBASIN 0 -• 5 3,308 3,324 329 2,147 0 222 9,330 . 5 -1.0 347 71 8,084 1,305 0 0 9,807 1.0 -1. 5 110 0 0 0 0 0 110 1.5 -2.0 0 165 0 0 0 0 165 TOTAL 3,765 3,560 8,413 3,452 0 222 19,412 BIGHORN SUBBASIN 0 .5 4,478 0 1,309 0 0 0 5,787 • 5 -1.0 1,608 3,451 0 0 0 0 5,059 1.0 -1.5 0 2 191 0 0 0 0 2,191 TOTAL 6,086 5,642 1,309 0 0 0 13,037 MID-YELLOWSTONE SUBBASIN 0 .5 16,000 1,691 0 0 0 0 .5 -1.0 3,180 4,358 0 0 0 0 TOTAL 19,180 6,049 0 0 0 0 TONGUE SUBBASIN 0 • 5 21,947 0 0 0 0 0 21,947 KINSEY AREA SUBBASIN 0 • 5 3,248 0 0 l,lBO 0 0 4,42B • 5 -1.0 0 0 0 0 0 0 0 1.0 -1.5 308 0 0 0 0 0 308 TOTAL 3,556 0 0 1,180 0 0 4,736 PO\'/DER RIVER SUBBASIN 0 .5 74,224 0 0 0 0 0 74,224 .5 -1.0 981 0 0 0 0 0 981 TOTAL 75,205 0 0 0 0 0 7 5' 205 LmiER YELLmiSTONE SUBBASIN 0 -.5 23,677 1,804 1 '775 0 0 0 27,256 • 5 -1.0 1,813 4,992 100 0 0 0 6,905 1.0 -1. 5 0 2,599 0 0 0 0 ' 2,599 1.5-2.0 0 805 0 0 0 0 805 2.0 -2.5 0 105 0 0 0 0 105 TOTAL 25,490 10,305 1,875 0 0 0 37,670 BASIN SUMMARY 0 -.5 187,118 6,819 3,413 3,327 0 222 200,899 . 5 -1.0 7,929 12,872 8,184 1,305 0 0 30,290 1.0 -1. 5 418 4,790 0 0 0 0 5,208 1. 5 -2.0 0 970 0 0 0 0 970 2.0 -2.5 0 105 0 0 0 0 105 TOTAL 195,465 25,556 11' 597 4,632 0 222 237,472 NOTE: This table should not be considered an exhaustive listing of all feasibly irrigable acreage in the Yellowstone Basin; it includes only the acreage identified as feasibly irrigable according to the geographic and economic constraints explained in this report. -54- Table 37. The increase in water depletion for irrigated agriculture by 2000 by subbasin Acreage Increase in Subbasin Increase Depletion (af/y) HIGH LEVEL OF DEVELOPMENT Upper Yellowstone 38,080 76,160 Clarks Fork 2,160 4,320 Billings Area 19,410 38,820 Bighorn 13,040 26,080 Mid-Yellowstone 25,230 50,460 Tongue 21,950 43,900 Kinsey Area 4,740 9,480 Powder 75,200 150,400 Lower Yellowstone 37,670 75,340 TOTAL 237,480 474,960 INTERMEDIATE LEVEL OF DEVELOPMENT BASIN TOTAL 158,320 316,640 LOW LEVEL OF DEVELOPMENT BASIN TOTAL 79,160 158,320 NOTE: The numbers of irrigated acres at the low and intermediate levels of development are not shown by subbasin; however, those numbers are one-third and two-thirds, respectively, of the acres shown for each subbasin at the high level of development. -55- Communities in southeastern Montana will demand more water if population increases accompany energy development. (Municipal population growth in the Yellowstone River Basin presumably would be unaffected by agricultural development, such as expanded irrigation.) The method used to project popu- lation increases due to energy development relied on the Montana Futures Process (MFP), developed by the Montana Department of Community Affairs. MFP simulates projected economic and demographic conditions. The economic calcula- tion combines economic bases and several assumptions to simulate employment levels by industrial sectors in labor market areas (LMAS). The demographic calculation simulates population levels from a combination of the simulated labor-force participation rates. MONTANA FUTURES PROCESS Although MFP can be used to estimate population levels for the 14 Labor Market Areas (LMAS), it is not designed to project population changes at the municipal level. The estimated labor-market population levels therefore had to be allocated among municipalities and communities in each labor market. This allocation was made according to informed judgments concerning likely spatial development of the new population based on historical trade patterns in each labor market area. MFP combines trends in employment and economic exports to avoid simulation of the effects of external economic changes while accounting for the region's population and employment baselines. The direct and indirect effects on employment of hypothesized developments are merged with long-term employment trends to yield simulated employment levels. These simulated employment levels are transformed into simulated population levels using employment and population multipliers assumed in the demographic calculation. The structure of the system is depicted in figure 4. Hypothesized development~ Montana I/0 Simulated Demographic Simulated Model __ ....,.employment ___. submodel ______..population / level level Employment base trends Figure 4. Montana Futures Process simulation-model structure. -56- ECONOMIC CALCULATION The economic calculation is based on employment trends of twenty-eight employment sectors (two for each LMA) at the state and LMA levels (figure 5). the LMA data were produced by grouping county employment data from 1969 to 1973 (U.S. Department of Commerce 1975) at the LMA level. Because of the short length of this series at the LMA level, the longer 1963-74 state-level series (Montana Department of Labor and Industry 1975) was used to produce long-term projections for the LMAs. The economic calculation relied on secondary data (U.S. Department of Commerce 1972, 1974, 1975a, 1975b) to analyze employment linkages (through an input-output model) in the state. Because this project was concerned with employment changes rather than industrial output changes, the input-output (I/0) matrix, which is usually formulated in terms of outputs, was transformed into employment terms. This transformation was based on output and employment ratios for Montana weighted by productivity projections from the Bureau of Labor Statistics (U.S. Department of Labor 1975). Because the I/0 matrix was constructed at the state level, it was necessary to allocate state-wide employment changes associated with a specific energy development level to 14 LMAs. The allocation of secondary employment (i.e., jobs resulting from the economic impact of jobs directly related to energy development) generally was based on the change in base activity. In other words, secondary employment was allocated to the LMA where the primary employment would occur, except for financial service and trade employment, which was partially allocated to one or more LMAs by taking into account distance from marketing centers and historical trade patterns. After the effects on employment of projected development levels were calculated and allocated to the LMAs, employment changes contingent on levels of energy development were merged with existing Montana employment trends by sector. The total employment estimations that resulted represented a simulated employment level for each LMA. Thus each si~ulated employment level repre- sents the sum of existing employment trends in each LMA plus the employment changes that would be associated with levels of energy development. DEMOGRAPHIC CALCULATION Multiplying a simulated employment level by the commonly used employment- population multiplier produces a simulated population level. The employment- population multipliers chosen here are keyed to LMA population data and range from 2.1 to 2.4, but all converge gradually to 2.0 by the year 2000. The convergence is consistent with a 25-percent increase projected over the next 25 years in the labor-force participation rate. The overall effect of a change in the participation rate would be to dampen employment-related migration, because employment opportunities would be absorbed internally. Because of this, the population multiplier assumed to apply in the future by MFP is, in general, lower than that which exists now. -57- I (.]1 co I Figure 5. Labor market areas in Montana. '··-··-------' ""?··-·· ) ----------------·-r-··---------J·--------·-·;·----------- . . I ··-------~---·-··-·· --:·-___ .. -.. T .. -.. --·--! · r 1 • I ·1 . I ') c-~ LINCOLN, N KALISPE!LL rj 0 0 f < >" ~RAVALLI ,/· ( . '"\ . .1 ·./ G L A c I E R ! T 0 0 L E ! HAVRE LMA SHELBY! LMA ! H I L L ! O r·-·--t.,,... I ~ L IBERTY • ·---. .J "'1...-, I.--... ~- L A I N E i , DANIELS~HERIOAN: 'v A L L E yl-~-----~ ! ,) ~ 0 [ GLASGOW l-MA L-----, .J •ROOSEVELT: , ~ I PHILLIPSr ·-·---·t. ,_ ___ --1 T E T 0 N LMA-Labor market area SMSA-Standard metropolitan statistical area MUNICIPAL POPULATION To estimate municipal water needs associated with hypothesized levels of energy development, it was necessary to allocate population increases in each LMA among affected municipalities. Because the MFP is not designed to simulate municipal population changes, additional information was re- quired to translate LMA employment and population changes to the city level. During this study, therefore, considerable attention was given to infor- mation on the likely spatial development pattern. The pattern was then compared with the distribution of existing settlement. Specifically, the economic activities associated with projected levels of development were disaggregated into subbasins, and we assumed that workers hired for jobs directly related to energy development would live in towns near each development area. A worker directly hired for work in any given energy development was assumed to head a household of 2.5 persons in the town closest to the energy development. The secondary population of workers generated by the primary activity was allocated among the towns of the region on the basis of past trade patterns in each basin. The total effect foreseen by the MFP for each town therefore includes the workers directly related to energy development, their families, and service sector population resulting from the new population in that town and other towns in its market area. The data in table 38 were derived from this study's assumptions of energy-development levels and from employment information from Freudenthal et al. (1974). After the direct-worker requirements were further refined according to subbasins, these requirements were put into the MFP model. The MFP model produced the total population for the indicated municipalities under conditions of low, medium, and high energy development, and the results are shown in table 39. INCREASED WATER USE ASSOCIATED WITH POPULATION GROWTH Table 40 summarizes the projected population increase (from table 39) for all subbasins of the Yellowstone Basin for 1985 and 2000 and lists the result- ing increases in water depletion under three levels of energy development. -59- Table 38. Permanent, direct energy-related employees in the Yellowstone Basin, 1985 and 2000 Subbasin 1985 2000 Mining Conversion Transportation Mining Conversion Transportation TONGUE Low 972 0 164 1687 0 283 Intermediate 1544 0 120 2087 360 346 High 2060 0 238 5148 2890 523 ROSEBUD Low 778 180 109 1298 1210 165 Intermediate 1200 360 158 2688 1390 320 High 1600· 360 188 4000 3740 280 POWDER Low 220 0 21 411 0 69 Intermediate 343 0 58 757 180 101 High 458 0 55 1140 180 154 BIGHORN Low 220 0 21 411 0 69 Intermediate 343 0 58 757 0 124 High 458 0 55 1140 180 161 -60- I 0"1 -I Table 39. Population simulations for low, medium and high energy development 1970a 1985 2000 Low Medium , High Low Medium Ashland 531 847 986 2,127 2,379 3,423 Billings 63 '729 79,472 79,872 80,197 94,999 95,533 Birney 13 91 129 129 60 70 Broadus 799 1,568 1,988 3,158 4,138 6,096 Busby 300 831 877 1,011 1,160 1,038 Colstrip 200 2,231 3,606 4,455 5,044 5,824 Forsyth 1,873 3,372 4,195 4,640 5,189 5,664 Glendive 6,441 7,168 7,168 7,168 8,341 8,341 Hardin 2,733 4,016 4,377 5,977 4,783 5,458 Lame Deer 650 934 944 2,337 1,062 1,012 Lodge Grass 806 885 939 977 1,090 1,215 Miles City 9,023 11,596 12,100 12,955 15,890 16,641 Sidney 4,551 5,120 5,120 5,120 6,032 6,032 aBaseline populations for Billings, Sidney, and Glendive are based on 1975 estimates. High 7,236 98,294 137 10,692 2,036 15,107 10,249 8 '713 7,094 1,442 1,462 20,254 6,404 Table 40. Population increases and water depletiona increases from municipal water use in the Yellowstone River Basin in 1985 and 2000 Level of Development Low Intermediate High Low Intermediate High Population Increase 1985 26,482 30,652 38,602 2000 56,860 62,940 94,150 Increase in Depletion (af/y) 2,970 3,430 4,320 5,880 6,960 10,620 aDepletion is assumed to be 100 gal per person rounded to the nearest 10 acre-feet. -62- The preceding sections present assumptions and methods used to estimate water requirements in the Yellowstone River Basin to meet the demands of energy development, irrigation, and municipal growth during the remaining years of the century. Three levels of development were considered. Table 41 summarizes the water demands arising from the activities assumed for each level of development by the year 2000. Table 42 itemizes the energy-development activities and associated water demands that appear in table 41. Appendix A details the demands of energy, irrigation, and municipal growth month by month that year in each of the subbasins. The projections shown in table 41 are the first step in estimating the impact of potential development on the Yellowstone Basin. Part II of this report contains the second step--calculation of how the streamflow in the basin would be affected by such development. In turn, these streamflow calculations helped define the physical, biological, and economic effects of water consumption in the Yellowstone River Basin contained in the other reports of this series. -63- I m ~ I Table 41. Water requirements by demand source in the Yellowstone Basin in 2000 Irrigation Municipal Energy a Level of develop-Acreage Associated Population Associated Associated ment Increase Depletion (af/y) Increase Depletion (af/y) Depletion (af /y) Low 79,160 158,320 56,860 5,880 48,350 Intermediate 158,320 316,640 62,940 6,960 147.160 High 237,480 474,960 94,150 10,620 321,190 aDetails of water requirements for energy use are in table 42. bThis total assumes that the same level of development occurs in all categories of consumption. Total In- crease inb Depletion (a f /y) 212,550 470,760 806,770 I 0'1 (J'1 I Level of Development Low Intermediate High Low Intermediate High Low ! Intermediate High I * Table 42. Increased water requirements for coal development in the Yellowstone Basin in 2000 ' Coal Development Activity Electric Gasi fi-Ferti-Strip Generation cation Sync rude lizer Export Mining COAL MINED (mmt/y) 8.0 7.6 0.0 0.0 171.1 24.0 7.6 o.o 0.0 293.2 32.0 22.8 36.0 3.5 368.5 CONVERSION PRODUCTION 2000 mw 250 mmcfd 0 b/d 0 t/d 6000 mw 250 mmcfd 0 b/d 0 tid 8000 mw 750 mmcfd 200,000 b/d 2300 t/d WATER CONSUMPTION (af/y) 30,000 9,000 0 0 * 9,350 90,000 9,000 0 0 31 '910 16,250 120,000 27,000 58,000 13,000 80,210 22,980 Total 186.7 324.8 462.8 48,350 147,160 321,190 No water consumption is shown for export under the low level of development because, for that development level, -it is assumed that all export is by rail, rather than by slurry pipeline. by Satish Nayak -67- MODEL VARIETIES Although many different types of water models have been proposed and used for water planning purposes over the past decade, these models have been classified for the purposes of the Yellowstone Impact Study into two categories: optimizing (or economic) models and watershed models. Optimizing models assume that the analyst is interested in finding the optimal solution providing lowest possible cost or maximum possible profit under a given set of constraints. These constaints may include water re- quirements, minimum flows, financial restraints, and other special considera- tions. These models are primarily meant for economic studies determining the operating policy for a system of reservoirs, new dam sites from a given set of potential sites for future demands, the allocation of water among several competitive users based on return or cost, or combinations of these. The Yellowstone Impact Study did not consider optimizing models for two reasons. First, the study did not address itself to such economic problems. Second, these models consider surface waters only and the study needed a model that could model the entire hydrologic characteristics of a basin. Watershed models, on the other hand, attempt to model the hydrologic characteristics of a basin by defining the relationships among the principal components of the hydrologic system, for example, precipitation, snow, tempera- ture, snowmelt, runoff, evapotranspiration, percolation, and ground water. The following five watershed models were examined for use in the study: 1) The Utah State Model; 2) Streamflow Synthesis and Reservoir Regulation (SSARR); 3) HYD-2; 4) SIMLYD-II; and 5) The State Water Planning Model (SWP). THE UTAH STATE MODEL The Utah State Model (Utah State University, 1973) emphasizes water quality. This model is divided into two parts: the hydrologic system and the salinity system. The hydrologic system includes programs which model precipitation (including snow), surface inflow and outflow, ground-water in- flow and outflow, and evapotranspiration determined through soil moisture. The salinity system consists mainly of the soil-salt system with its inter- action with diversion, surface flow and ground-water flow. The Utah State Model requires the following data: 1) inflow and outflow; 2) precipitation, including snowfall; 3) temperature; -68- 4) reservoir; 5) soil type with water holding capacity; 6) crop for finding potential evaptranspiration; 7) diversion; 8) salt concentration of ground-water and of reservoir water; and 9) soil chemistry for water quality. This hybrid model uses an analogue computer to analyze complex rela- tionships and a digital computer to calculate mass balance and salinity. Calibration is achieved by adjusting the parameters of the equations itera- tively unti1 the smallest value is reached for the objective function which is (Diff) where Diff equals the measured outflow minus the predicted out- flow. Because of its hybrid computational procedure and main emphasis on water quality, the Utah State Model was not selected for the Yellowstone Impact Study and so it is difficult to say how involved data gathering might have been. Based on the experience of the SWP model and its similarity with the Utah State Model, it appears that the data preparation would be a long process. Calibration seems to be difficult since the model must predict not only outflow but also salt concentration. The Utah State Model, which will handle two years of data on a monthly basis for one river basin, appears to be useful in determining how different water management practices (for example, irrigation policies, cropping pattern, leaching) will affect water quality downstream. STREAMFLOW SYNTHESIS AND RESERVOIR REGULATION (SSARR) The SSARR, developed by the U.S. Army Corps of Engineers, North Pacific, Portland, Oregon, is a good model for determining the daily operation of a system of reservoirs and for forecasting floods and flows. The character- istics of the SSARR model include a surface-water system, a snow system, a soil moisture system, a ground-water system, and flood routing. These characteristics are very broad and a detailed description of them can be found in Pro ram Descri tion and User Manual for SSARR Streamflow S nthesis and Reservoir Regulation U.S. Army Corps of Engineers 1972 • The SSARR requires massive amounts of data taken daily and even. hourly. The time increments can be as small as 0.1 hour in the case of flood routing. Many of the data that this model requires would be available only if special studies were conducted to collect them. In a broad sense, the following types of data are needed: 1) inflow and outflow; 2) precipitation including _snow; 3) temperature; 4) reservoir storage including area-capacity curves; and 5) tables for parameters such as soil moisture index against percentage of runoff, precipitation against evaporation reduction factor, per- centage of season runoff against percentage of snow-covered areai and many more. The detailed list can be found in the SSARR manua • -69- The SSARR is calibrated by a trial-and-error method that appears to be a long and difficult process since there are many interacting empirical parameters needing adjustment as more data become available. Although this model can predict daily flows, the Yellowstone Impact Study requires analyses over longer periods, and so the SSARR model was not selected. HYD-2 Program HYD-2, a generalized hydrologic model of a river system that can analyze up to fifteen stream-flow control points, is essentially an accounting model needing no calibration (USDI 1974). At each control point, some or all of which may be reservoirs, a mass balance is carried out and all losses or gains are accounted for. Although this program models only the surface water system, gains and losses due to ground-water activities are a part of the model. This model requires the following data: 1) inflow and outflow; 2) demand at each control point; 3) reservoir storage with area-capacity curves; 4) pan evaporation coefficients at each reservoir site; and 5) losses or gains at each control point due to ground-water activity in the area. Since the main data requirements are the inflow and outflow values and estimated ground-water activity at each control point, the data preparation is less complicated than for the Utah State, the SSARR, or the SWP. This model can simulate the monthly yield of a subbasin for fifty years but cannot be used _for water-quality calculations. HYD-2 was developed by the U.S. Bureau of Reclamation (USDI 1974). SIMYLD-II SIMYLD-II (Texas Water Development Board 1972) is based on the concept that a physical water resource system can be transformed into a capacitated network flow problem. Essentially an accounting model, since the mass balance equation must be satisfied at each control point, SIMYLD-II needs no calibration and has optimization built into it. This model's data re- quirements are similar to those of HYD-2 and are as follows: 1) inflow and outflow; 2) reservoir storage with area-capacity curves; 3) demand or diversion at each model point; 4) pan evaporation coefficients at each reJervoir site; 5) priorities for meeting the demands; and 6) operating rules for the reservoirs. SIMYLD-II is used primarily for two purposes: first, to simulate the least costly operation of a system subject to a specified sequence of demand and hydrology; and second, to find the yield of a subbasin or reservoir within a basin. SIMYLD-II does not have the capability for water-quality calculations. This model, designed to simulate the operation of more than -70- one reservoir in a system, assigns to each reservoir a priority that is converted to a cost in order to find the optimal solution. THE STATE WATER PLANNING MODEL The State Water Planning Model (SWP) (Montana University Joint Montana Resources Council 1972), a watershed model which can closely simulate the hydrology of a river basin, includes four major subsystems: a surface water system dealing with aspects such as precipitation, runoff, inflow, and reser- voirs; a snow system dealing with snowfall, snowmelt, and sublimation losses; a ground-water system simulating ground-water activities such as deep percola- tion, ground-water storage, and ground~water outflow; and a soil-water system dealing with soil moisture and evapotranspiration losses. This model has been modified to include water quality calculations in total dissolved solids (TDS). The SWP requires extensive data preparation including: (a) inflow and outflow; (b) precipitation including snowfall; (c) temperature including frost data; (d) pan evaporation coefficients at each reservoir site; (e) soil type with water holding capacity; (f) crop data for finding consumptive use and potential evapotranspiration; (g) diversion data; and (h) regression equations for TDS calculations. All relationships among the elements of the model are expressed as a system of linear equations that represent the basin characteristics and are obtained from knowledge about the area and the relationships described in hydrologic literature. Calibration criteria are based on a zero trend in the available ground-water capacity. Calibration is accomplished by running the program iteratively and changing some of the relationships in the system of equations. This model can be used to determine the yield of a basin under a given operating policy. Although SWP is not meant to provide information for controlling or correcting the water quality of the outflow, water quality calculations can be made on the outflow. MODEL COMPARISON Although the Utah State Model and the SSARR programs were not used, pre- liminary evaluation of these programs showed that they would not meet the requirements of the study. The Utah State Model was eliminated mainly for its hybrid computational procedure and its narrow emphasis on water quality, although other factors indicated that it would be unsatisfactory. This study required a model that could simulate much longer periods than the twenty-four months that the Utah State Model could simulate. Also, the Utah State Model's data preparation and model calibration appeared to be a longer and more difficult process than that in other models that could provide information more useful to the study. The SSARR was eliminated because of its narrow -71- range simulating the day-to-day operation of a system of reservoirs, and because it requires massive amounts of data that have not been collected. The HYD-2, SIMYLD-II, and SWP programs were all run for detailed evaluation and comparison. The results of the evaluation and comparison may be found in table 43 and the criteria used to evaluate the models are listed in table 44. When the comparison was made, it was apparent that SIMLYD-II has all the capabilities that HYD-2 has plus additional capabilities and therefore HYD-2 was dropped from consideration. The SWP and the SIMLYD-II programs were both good models for the study, but the SWP was more complete than SIMYLD- II. Also, the SWP had water quality abilities that SIMYLD-II lacked. And using the SWP had another advantage: since the program was developed under a grant from the Water Resources Division of DNRC to the Water Resources Research Center at Montana State University, Bozeman, Montana, experts who worked on that project would be available for any necessary modification of the SWP program. Therefore, the State Water Plan (SWP) was selected for the Yellowstone Impact Study and applied to the Yellowstone Basin. -72- Type of Model a Data Calibration Simulation Table 43. Model comparison State Water Plan A hydrologic model using a system of equations defining the interaction of ground-water, sur- face water, snow- melt, and other subsystems. Only one reservoir per basin may be . simulated. Simulation, :in a limited sense, can be carried out for basins without a reservoir. No optimization. Temperature depend- ent data are required. Soil moisture data are required. Lengthy calibration is required. Com- puter time for each calibration run approximately equals that for a simulation run. HYD-2 An accounting model mainly simulating sur- face waters. More than one reservoir per basin may be simulated. Simulation, in a limited sense, can be carried out for basins without a reservoir. No optimization. No temperature dependent data are required. No soil moisture data are re- quired. No calibration is needed. SIMYLD-II An accounting model mainly simulating surface waters. More than one reservoir per basin may be simulated • Simulation cannot be carried out if shortages occur. Optimization is possible. No temperature dependent data are required. No soil moisture data·are re- quired. No calibration is needed. All three models may be used for finding the yield of a basin. The operating criteria are less rigid and limited for the SIMYLD-II model than for the SWP or HYD-2 models. -73- Table 43 Continued. Computer time Learning time Water quality State Water Plan Presently, each computer run costs approxi- mately $30.00 for 360 months. SWP is not an "off-the-shelf" model. A good understanding of the subsystems and their interrela- tionships is required. A knowledge of matrix inversion is desirable. Water quality is calcu- lated but not direct- ly controlled. HYD-2 Presently, each computer run costs approxi- mately $6.00 for 360 months. HYD-2 is an "off- the-shelf" model of the accounting variety. No prov1s1on for water quality. SIMYLD-II Presently, each computer run costs approxi- mately $12.00 to $14.00 for 360 months. SIMYLD-II is an "off-the-shelf" model of the accounting variety. The optimization method requires an understanding of network flow theory. No provision for water quality. aData requirements and preparations are more complex and time consuming for SWP than for HYD-2 or SIMYLD-II. Monthly data is acceptable to SWP up to 360 months and HYD-2 and SIMYLD-II up to 600 months. -74- Table 44. Suggested model evaluation criteria 1. Validity of results. 2. Ease of verification. 3. Ease of learning and use. 4. Cost/benefit. 5. Data requirements. 6. Ease of modifying to simulate different situations (flexibility). 7. SmallP.st time increment which can be used. B. Accounts for known physical, hydrologic relationships. 9. Assumptions required and their validity. 10. Economics built in (optimizing). 11. Subbasin interaction capability. 12. Calibration effort required. 13. Sophistication of output. 14. Ease of debugging problems. 15. Outputs available in addition to yields and flows. 16. Prediction capability. 17. Existing documentation. 18. Routing capability. ~ 19. Water quality. l 20. Physical availability to other users. ,I -75- HOW THE SWP MODEL WAS USED The SWP was modified to include water quality calculations and to make the program ready to use in each subbasin with a minimum of changes. Because watershed models must be tailored to each subbasin, the program was divided into two sections, one that included subroutines independent of the subbasin under study and another containing subroutines dependent on that subbasin. By limiting the amount of reprogramming of the model necessary for each subbasin, considerable time and money was saved. The revised program includes many new subroutines. The model consists of sixteen linear equations that describe the inter- relationship of the four major subsystems: including a surfac,e water system, a snow system, a ground-water system, and a soil water system. Each equation represents a secondary datum whose value is obtained during the calibration phase of the modeling. The primary input of the equations consists of inflow, outflow, precipitation, reservoir storage, and temperature. The system of linear equations is solved for each month of the study period, keeping a link from one month to the next, especially in variables dealing with storage. Despite the program changes and the inclusion of water quality calcula- tions, the program's variable names, formats, and basic character remained essentially the same as the program developed by Boyd and Williams (Montana University 1972). The water quality subroutine, added to meet the requirement of the Yellow- stone Impact Study for water quality calculations,can take twelve monthly regression equations for total dissolved solids (TDS) based on flows. The subroutine calculates the TDS for the incoming flow as well as the outgoing flow and has provisions for two level~ of salt pickup by return flows. A brief description of procedure used w1th the SWP follows. CALIBRATION Calibration of all subbasins was based on data (see "Data Preparation," below) covering the 360 monthly time increments from 1944 through 1973. Calibration begins by using a simple program to calculate the initial coefficients of the model. These initial coefficients are then used in an annual version of the SWP model that is then run with the data covering the thirty individual years. The initial coefficients are adjusted and the model is reiterated two or three times until final values for the annual model's coefficients are reached. The annual model (which becomes the monthly model with the reduction in scale of some factors and the addition of systems simulating such details as -76- snow pack and soil moisture) also acts as a basis for assigning certain co- efficients. The monthly model is calibrated by running data covering the 360 months using the annual ~odel's coefficients and adjusting them until the model is consistent with the data. The calibration of the monthly model requires more runs and adjustments of the coefficients of the annual model since the monthly model uses 360 months of data and considers twice as many variables. In addition, although the model uses the relationships between monthly average temperature and variables such as snowmelt, potential evapo- transpiration, and soil moisture, the responses of these variables are more dependent upon maximum and m1n1mum temperatures; therefore, determining the final coefficients for the monthly model requires some subjective judgment. The monthly model used in this study differs slightly from the original SWP model. The subsystems for ice formation and irrigation diversion devia- tion were eliminated to reduce the size of the model's matrix. The sub- systems for subsurface outflow, subsurface inflow, and snowfall were treated outside the system of equations, another step to reduce the matrix size. SIMULATIONS After the model had been calibrated for a particular subbasin, it was ready for simulations. Scenarios describing low, intermediate, and high water use (which are explained in Part 1 of this report) were run for each subbasin. The model can perform simulations of the following situations and policies: 1) Keeping a reservoir as full as possible, making releases only when required to augment flows and releasing excess flows only when the reservoir is full. 2) Keeping a reservoir as full as possible making releases to augment irrigation flows (when the reservoir inflow is less than the irrigation flow) plus a minimum required flow such as the Department of Fish, Wildlife and Parks would request; and 3) A system that has no reservoirs and so has no capacity to augment or regulate flows except through additional diversion. DATA PREPARATION Inflow and outflow data for all subbasins were obtained from computer files (USDI) and Water Supply Papers provided by the USGS. Precipitation and temperature data were obtained from the SWP model data bank (Montana Univer- sity) and the U.S. Climatological Records. Montana Agricultural Statistics (Montana Department of Agriculture 1946-74) provided crop data for determining the potential evapotranspiration on a monthly basis for all subbasins. Root zone capacity was calculated from the soils maps provided by the Soil Conserva- tion Service. Bureau of Reclamation data on diversion projects in the Yellow-' stone Basin were used to estimate the diversion requirements for most of the subbasins on the mainstem. A brief description of the procedure used in preparing the data follows. -77- Priority The largest use of water in the Yellowstone Basin is for agriculture, including irrigated farming, dryland farming, and ranching. Municipal and industrial water uses, though important, are relatively small, at present, compared to agricultural water use. With recent attention on the coal development and thermal energy production potential in the southeastern part of Montana, the water demand for energy has become significant. In this study, water for energy was treated as an industrial demand. Municipal and agricultural demands were given priority over energy demand for all simulation studies. Exports and Imports It is assumed that all diversions from the stream are meant for use in that subbasin; however, there are situations calling for diverted water to be used in a neighboring subbasin. In such cases, this water is treated as an export in one subbasin and an import in the receiving subbasin. In most cases, diversion will be all along the length of the river, but, for the model, diversions are summed to give the net diversion for the subbasin. Actual diversion data from projects in the basin were used as the basis for calculating totaJ diversion in that basin. If the data were not complete, an average value was used in place of the missing data or period. In basins where the diversion data were incomplete or nonexisten~ like the Powder River Basin, the diversion data were created by using consumptive use requirement, area, precipitation, and the irrigation practice used. The total irrigated acreage for different subbasins was obtained from irrigated cropland harvested data found in Montana Aaricultural Statistics (Montana Department of Agriculture 1946-74). Streamflow. Inflow and outflow data for each subbasin were obtained from the gaging stations nearest to the subbasin boundary. In some cases the gaging stations were either deep inside or outside the drainage boundaries. In such situations, flows were estimated from the proportions of the drainage area, a regression equation, or both, or from some relevant information that can be used in predicting flows. Each basin was treated differently de- pending on availability of information. Precipitation. To obtain the average precipitation for the area under consideration, all weather stations with thirty years of records were con- sidered. If the station had a few missing observations, they were syn- thesized by using regression analysis or by averaging. In a few cases, where the stations were not uniformly spaced or did not cover the entire area, the Thiessen polygon method was used. In these cases, mean precipitation was calculated by using the following expression: A.P. p =~~ m ~ A. 1 where: P = mean precipitation for the subbasin in inches m -78- P. = precipitation of the ith measuring station in inches l A. =area corresponding to the ith measuring station in acres l If the gaging stations were all uniformly spread over the area, then: p = m where: P = average precipitation for the subbasin in inches m P. = precipitation of the ith measuring station in inches l n = total number of measuring stations Temperature. Temperature data were treated exactly the same way as pre- cipitation data. All weather stations with adequate records were used in calculating the mean value. Missing data or values were created using an appropriate method. The Thiessen polygon method for finding average tempera- ture was used whenever appropriate: · A.T. T -L l l m -A. l where: T = average temperature for the subbasin in Fahrenheit degrees m T. = temperature at the ith measuring station in Fahrenheit degrees l A d . t th . th . t t . . . = area correspon 1ng o e 1 measur1ng s a 1on 1n acres l The following equation was used to obtain the average value of the temperature in cases where the measuring stations were uniformly spaced over the basin: T m where: T = average temperature for the subbasin in Fahrenheit degrees m .th T. = temperature at the 1 measuring station in Fahrenheit degrees l n = total number of measuring stations. Reservoir Storage. Reservoir storage was considered only if storage could be used as a regulating device for the flows. In subbasins having more than one reservoir, the reservoirs were lumped to give the net storage capacity of the basin. Channel storage was not considered because it could not be used for regulation of flows. Root Zone Capacity. A wide range of soil types exists within the root zone of the drainage area. Each of these soil types exhibits a different capacity for holding percolating waters. This information was used to deter- mine the field capacity of the subbasin (i.e. the area weighted average of soil moisture holding capacity) using the following equation: FC = lA.C. J. J. where: FC = field capacity of the subbasin in million acre-feet A. = area in million acres per soil type J. c. = root zone capacity in feet for A. J. J. Potential Evapotranspiration. Potential evapotranspiration values were determined on a monthly basis for individual ~egetative types. For agricul- tural crops, the Modified Blaney Criddle method (USDA 1970) was used and for native vegetation the Thornthwaite method (USDA 1970) was applied. These quantities were added together to provide the net potential evapotranspiration for each basin by month. The crop acreage data were obtained from Montana Agricultural Statistics (Montana Department of Agriculture 1946-74). THE ANNUAL AND MONTHLY MODELS ANNUAL MODEL Definition of the model began with determining the relationships between the variables. Since the study used the SWP model, the study model used the same nomenclature and relationships as the original SWP. Definitions of the annual model's variables (expressed in million acre-feet) follow: Xl = Surface outflow X2 = Surface inflow X3 = Initial storage X4 = Terminal storage X5 = Precipitation X6 = Surface loss or the consumptive use X7 = Subsurface outflow XB = Subsurface inflow X9 = Initial available capacity XlO = Terminal available capacity Xll = Percolation Xl2 = Subsurface discharge The following equations defined the model's relationships: 1) Surface loss: X6 = -Xl + X2 + X3 -X4 + X5 -Xll + Xl2 2) Subsurface outflow: X7 = Cl + (K3) (Xl) 3) Subsurface inflow: XB = C2 + (K4) (X2) 4) Terminal available capacity: XlO = X7 -XB + X9 -Xll + Xl2 -80- 5) Percolation: Xll = SF (K7)(X2) + KB(X3+X4) + (KlO)(Xl2) + X5 6) Subsurface Discharge: Xl2 = C4 -C3(X9 + XlO) 7) Assumptions: XS = (K2) (X7) x7 + x8 = Kl cx1 + xz) (K6) (Xl2) = C4 X9 = XlO X9 = X5 + X2 (As/Ab) where: X2 = average inflow into Montana's portion of the Yellowstone Basin A = area of the subbasin in acres s Ab = area of Montana's portion of the Yellowstone Basin in acres SF = scale factor Initial Coefficients (C and K Values) Choosing the model's initial coefficients (K values) is the most diffi- cult part of this procedure and requires subjective judgment based on a thorough knowledge of the hydrology of the basin. Once these K values had been selected, they were read into a simple program using thirty-year average values of Xl, X2, X3, X4, and X5 for the basin. The output of this program consisted of initial coefficients for the annual version of the model (Cl, C2, C3, C4) and the initial values of X9 and SF. These C values, in turn, were used to run an annual version of the model using data from each of the ihirty years. Each time a run was made, the C values were adjusted so that X9 = XlO which implies that during the thirty-year period, the ground-water storage is neither built up nor depleted. Once the condition of zero trend was achieved, the C values had been adjusted until they became the values of the annual model's coefficients. The coefficients of the monthly model could then be developed from the coefficients of the annual model through a similar though more complex process. Table 45 shows the values of Kl through KlO used for each of the nine subbasins as well as the final values of Cl, C2, C3, C4, and SF. In addition to these values, the initial value of X9, the average value of XlO and the sum of all X6 are listed in the same table. 1 A bar above the variable X's indicates an average value. -81- I co rv I Coefficient Kl K2 K3 K4 K5 K6 K7 K8 K9 KID Area in M Acres C1 C2 C3 C4 SF x9 Initial x-10 Sum of all X6 Upper Yellowstone .050 .960 .015 .015 .050 2.000 1.000 .zoo 1.000 .500 3.805440 .106151 .131857 . Oll646 .448829 .020880 9.606533 ?.634332 93.982705 Clarks Billings Fork Area .040 .030 .960 .970 .015 .015 .015 .015 .060 .060 2.000 2.00 1.000 1.00 .200 .250 1.000 2.000 .500 .500 1.001376 . 019017 .079541 .0210U6 .071450 .010041 .068000 .109762 .590000 .176100 .034300 2.677895 2.020000 2. 734140 2.167467 67.403834 78.002623 Table 45. l~odel Coefficients Hid-Kinsey Lower Bighorn Yellowstone Tongue Area Powder Yellowstone .040 .030 .030 .008 .030 .020 .965 .970 .970 .960 .980 .960 .020 .015 .015 .006 .015 .OlD .020 .015 .015 .006 .015 .010 .060 .060 .020 .060 .020 2.000 2.000 2.000 1. 250 2.000 1.250 1.000 1.000 1.000 .500 1.000 .500 .250 .250 .250 .250 .250 .250 2.000 2.000 2.000 2.000 2.000 2.000 • 500 .500 .500 .500 . 500 .500 2.266788 2.463360 .933812 2.51090 3.980582 .056322 .122501 .005217 • 018502 .005478 .95738 .054806 .ll5654 .005004 .016296 .006587 .087535 .033500 .069932 .003042 .017350 .003684 .004054 .397499 . 954247 .061278 . 2188ll .05367h .228189 .026370 .035561 .003572 .027458 .004255 . 013678 2.788641 3.033000 3.382400 1. 201977 3.624976 5.550416 2.968178 3.4ll503 3.392497 1.279755 3.63?492 5.625278 66.565216 N.A. 82.419387 27.323242 87.031952 139.858505 MONTHLY HODEL The monthly model was derived from the annual model by adding more structure. For example, an annual model, having no temperature-dependent variables, treats evaporation losses from the reservoir or from streams or from vegetation as a single loss. The monthly model, however, attempts to separate these losses into different components such as evapotranspiration, evaporation from reservoirs, and the losses from the stream surface, thus accounting for seasonal temperature variation. The precipitation, for example, is assumed to be snowfall or rainfall depending upon the temperature. The monthly model was composed of the following five subsystems: 1) SSl: Stream-Reservoir 2) SS2: Snow 3) SS3: Runoff 4) SS4: Ground \1ater 5) SS5: Soil Water These five iubsystems require the following fifteen parameters, expressed in million acre-feet: 1) SSl Parameters. 2) SS2 Xl = stream out flow X2 = stream in flow X3 = initial reservoir storage X4 = terminal reservoir storage X6 = stream-reservoir evaporation Parameters. Xl4 = sublimation Xl5 = initial snow storage Xl6 = terminal snow storage 3) SS3 Parameters. X5 = precipitation X20 = runoff evaporation loss X27 = irrigation import 4) SS4 Parameters. X7 = ground-water out flow X8 = ground-water inflow X9 = initial ground-water capacity loss XlO = terminal ground-water capacity 5) SS5 Parameters. X23 = initial soil-water storage X24 = terminal soil-water storage X25 = evapotranspiration loss -83- 6) SSl-2 (Stream-Reservoir-Snow) Parameters. XlB = ice formation X31 = irregular ice formation ( X31 < 0, T ~ 32°) 7) SS2-l (Snow-Stream-Reservoir) Parameter. X31 = irregular snowmelt (X31>0, T:::S32°) 8) SSl-3 (Stream-Reservoir-Runoff) Parameter. X28 = irrigation diversion 9) SS3-l (Runoff-Stream-Reservoir) Parameters. Xl9 = ground-water runoff plus irrigation runoff X31 =precipitation runoff (T>32°) 10) SSl-4 (Stream-Reservoir-Ground Water) Parameter. Xll = stream-reservoir percolation 11) SS2-3 (Snow-Runoff) Parameters. Xl7 = snowmelt X22 = irregular snowmelt ( X22 < 0, T :::s 32°) 12) SS3-2 (Runoff-Snow) Parameters. Xl3 = snowfall X22 = irregular ice formation (X22>0, T ~ 32°) 13) SS3-5 (Runoff-Soil Water) Parameters. X21 = ground-water infiltration plus irrigation infiltration X22 = precipitation infiltration ( T > 32°) 14) SS4-3 (Ground Water-Runoff) Parameter. Xl2 = ground-water discharge 15) SS5-4 (Soil Water-Ground Water) Parameter. X26 = soil-water percolation -84- Three additional parameters were defined: X29 = irrigation diversion deviation X30 = irrigation runoff X32 = 1.0, a system constant Unity-Coefficient Equations The five subsystems gave rise to five balance equations: 1) Xl -X2 -X3 + X4 + X6 + Xll + XlB -Xl9 -X27 + X28 -X31 = 0 2) Xl3 -Xl4 + Xl5 -Xl6 -Xl7 + XlB + C(9,22)X22 + C(9,3l)X31 = 0 3) X5 + Xl2-Xl3 + Xl7-Xl9-X20-X21-X22 + X27 + X28 + C(l5,3l)X3~= 0 4) X7 -XB + X9 -XlO -Xll + Xl2 -X26 = 0 5) X21 + C(l6,22)X22 + X23 -X24 -X25 -X26 = 0 C(9,22) = 1.0 when T ::; 32°, otherwise C(9,22) = 0; C(9,31) = 1.0 when T::; 32°, otherwise C(9,31) = 0· ' C(l5,31) 0 . = 0; = -1.0 when T>32 , otherwise C(l5,31) C(l6,22) = 1.0 when T>32°, otherwise C(l6,22) = 0 For parameters other than measured data and those that can be obtained from the balance equations, empirical relationships were obtained either from the annual model by scaling them accordingly or by choosing a relationship as given in the third volume of Devel~p~ent of a ~tate_Water Plan~ing Model Montana University.l972). The emp1r1cal relat1onsh1ps follow. Stream-Reservoir Evaporation Loss 1) X6 = C(l,2)X2 + C(l,l9)Xl9 + C(l,28)X28 + C(l,3l)X31 + C(l,32)X32 C(i,j) equals the coefficient for the jth variable in the ith row. For X6, all coefficients are temperature dependent, and the exact relationship varied from one subbasin to the next. The general expression for these coefficients for this equation is: 1 This system of equations uses unity coefficients, C(i,j) coefficients, and C (i,j) coefficients. Unity coefficients normally belong to a balance equa- tion and remain the same for all subbasins. C(i,j) coefficients are temperature-dependent coefficients that vary from one subbasin to another. C (i,j) coefficients are independent of the temperature and usually are obtained from the annual.model either by scaling down the coefficients or carrying them as they are. C(i,j) and C (i,j) coefficients may be found in appendix B. -85- C(i,j) = aT+ bT 2 where: T = actual temperature a and b = constants selected so that the curve of the function duplicates the curve made when evaporatjon loss is plotted against temperature The losses due to evaporation are proportionately larger at higher temperatures than at lower temperatures. This nonlinearity with temperature is built into these coefficients. Note that, except for X32, all flows are streamflows, nnd the losses are called stream losses. The coefficient C(l,32) accounts for the losses from the reservoirs. The coefficient C(l,32) is calculated in subroutine SURFAC as follows by multiplying the pan evaporation coefficient by reservoir surface area. ~ ;t ream-Reservoir Percolation 2) Xll = C(2,3)X3 + C(2,4)X4 + C(2,19)Xl9 + C(2,22)X22 + C(2,28)X28 + C(2,3l)X31 These coefficients do not depend on temperatures, and are usually ob- tained from the annual model. C(2,3) equals C(2,4) which equals l/12th of the corresponding annual coefficient. C(2,2) has the same value as the correspond- ing annual coefficient (C value). Ground-Water Discharge 3) Xl2 = C(3,9)X9 + C(3,10)Xl0 +(C3,32)X32 The values for C(3,9), C(3,1Qj and C(3,32) are obtained by dividing the corresponding annual coefficients (C values) by 12. Sublimation 4) Xl4 = C(4,15)Xl5 + C(4,16)Xl6 Sublimation losses were considered to be 2 to 5 percent of the snow cover. A sublimation loss is actually a function of dew point, wind, and temperature, but except for temperature no other data are readily available. Since the losses are not high, an average value was used for all winter months irrespective of the temperature. The average value changed from one subbasin to next. Snowmelt 5) Xl7 = C(5,l))Xl3 + C(l0,15)Xl5 A C(5,13) = -2- -86- C(l0,15) = A where: 2 + Xl5 A = C(T-32)K6 + (~-32) + K7(X5 (bK6)+b 2 ' T = actual temperature b = number of degrees above 32 at which all snow melts. K6 and K7 are the factors which affect the rate of snowrnel t. The first component in the above expression accounts for the ternper~ture effect on snowmelt, whereas the second one considers the impact of rainfall on snowmelt rate. In the event that A is greater than 1.0, A is set equul to 1, thus ensuring that snowmelt will not exc~ed the snowpack. Ground-Hater Runoff plu~ Irrigation Runoff 6) Xl9 = C(6,12)Xl2 + C(6,27)X27 + C(6,28)X28. Runoff Evaporation Loss 7) X20 = C(7,5)X5 + C(7,12)Xl2 + C(7,17)Xl7 + G(7,28)X28 8) X21 = C(8,12)Xl2 + C(8,27)X27 + C(8,28)X28 Terminal Surface \:later Storaqe 9) X24 = X21 + C(9,22)X22 + X23 -X25 -X26 ~1hen FCil" ·1n X24 = rc 1,. · v1hen X24<FC 11" , and ·1n ·1n X24 = FC 1·1hen X24 > FC where: rc,,. = minimum soil moisture capacity ·1n Evaoor8tion Loss 10) X25 = X21 + C(l0,22)X22 + X23 -X24 -X26 X25 = PET, l'lhen X24 < FC 11 . '1n where: PET = potential evapotrans~iration Percolation ~ X24 ~ FC 11) X26 = C(ll,2l)X21 + C(ll,22)X22 + C(ll,23)X23 + C(ll,32)X32 C(ll,32) = RE (X24-FC) when X24>FC, othen1ise C(ll,32) = 0 -87- where: RE is a fraction between 0 and 1. The term (X24 -FC) is the excess water that soil cannot absorb and hence it must either be runoff or should percolate into ground water or both. RE(X24 -FC) is the amount of excess water that goes into ground water. Precipitation Runoff or Balance 12) X31 = Xl -X2 -X3 + X4 + X6 + Xll + Xl8 -Xl9 + X28 These twelve equations coupled with balance equations 2 through 5 (the first balance equation and the precipitation runoff equation are equivalent) constituted the monthly model. There were five fewer equations in this model than the model developed at the Water Resources Research Center under Boyd and Williams (1972), mainly due to the different treatment of equations for X7, XS, and Xl3 and the elimination of equations for Xl8 and X30. Since X7, XS, and Xl3 depend on known quantities Xl, X2, and X5, respectively, there was no need to consider them as a part of the system of equations for the solution procedure. Equations for Xl8 and X30 were considered to be unnecessary for the study. Exclusion of these equations reduces the matrix size from 21 x 21 to. 16 x 16 and thereby reduces cost in computer time by 30 to 40 percent. Calculations for X7 and XS are carried out in the mainline program, whereas Xl3 (the snowfall system) is obtained from the subroutine COMPUT. CALIBRATION OF THE MONTHLY MODEL AND CONTROLLABLE VARIABLES Though the monthly model was derived from the annual model, it still needed calibration. The calibration procedure was similar to the one used in the annual model, except that the number of controllable variables was larger than for the annual model. Some of the important controllable vari- ables follow. Rainfall Moving Average Outflow from a basin, besides being a function' of many variables, was dependent on the precipitation in that basin. Furthermore, all the outflow in a given month was not necessarily due to all the precipitation in that month. It is more than likely that the precipitation in a month influences the outflow for up to a month or two later. For the calibration of the Yellowstone River Basin, the precipitation effect was carried over to the next month. For months when all precipitation was determined to be snowfall, the precipitation averaging was ignored. E = a(g) + (1-a)t where: E = effective rainfall a = fraction of precipitation in a month resulting in outflow in that month -88- I·, ~ I g = current month's precipitation t = previous month's precipitation Snowfall and Snowmelt The snow subsystem serves as a mechanism in the model to delay the runoff due to snowfall from the winter months when the snow falls to the summer months when it all melts. ( T-b Xl3 = 1 -~)(X5) where: Xl3 = snowfall T = temperature in degrees Fahrenheit b = temperature in degrees Fahrenheit below which all precipi- tation is snowfall X5 = precipitation The value of b was chosen with the topography of the area and the climate conditions in mind. For example, in the Bighorn Subbasin, the value of b was 20°F. The snowmelt rate was another important factor in the calibration phase of the monthly model. Spring runoffs from the basin were mainly due to the snowmelt, and runoff and snowmelt were matched to reflect the cause and effect relationship. From the system of equations, one can see that the snowmelt was a prime component of the soil moisture system, which in'turn was a major contributor to the ground water recharge. Thus, a snowmelt rate eventually affected the ground water, potential evapotranspiration, and runoff. Soil Water Percolation Rate X26 = SF (X5 + X23) (d + X5 + X23) where: X26 = soil water percolation SF = scaling factor X5 = precipitation X23 = initial soil water storage d = dampening factor (X5 + X23) The term (d + X5 + X23) takes into account the effect of precipitation and the soil moisture condition on the pecolation rate. The dampening factor d is in most cases equal to 1.0, and by changing the value of SF the ground water recharge could be changed. -89- Initial values for the above controllable variables were selected using experience and knowledge of the basin. The initial run was then made. The output from this run became the basis for making changes in some of the controllable variables, and the model was rerun. This iterative process was continued until: 1) The initial ground water storage equaled the terminal ground water storage for the· study period; 2) The average ground water storage equaled the average ground water storage from the annual model; and 3) The total system loss in the monthly model equaled the total system loss in the annual model. The first two conditions were easier to satisfy than the third condition. For the third condition, a variation up to 5 percent was considered to be acceptable, whereas the first two conditions were met well within the second decimal place of accuracy. The monthly model was said to be calibrated if all of the three conditions were satisfied simultaneously. The system of equations for the calibration of a subbasin are gathered below: 1) X6 = C(l,2)X2 + C(l,l9)Xl9 + C(l,28)X28 + C(l,3l)X31 + C(l,32)X32 2) XlO = X7 -XB + X9 -Xll + Xl2 -X26 3) Xll = C(3,2)X2 = C(3,3)X3 + C(3,4)X4 + C(3,19)Xl9 + C(3,28)X28 + C(3,3l)X31 4) Xl2 = C(4,9)X9 + C(4,10)Xl0 + C(4,32)X32 5) Xl4 = C(5,15)Xl5 + C(5,16)Xl6 6) Xl6 = Xl3 -Xl4 + Xl5 -Xl7 + XlB + C(6,22)X22 + G(6,3l)X31 7) Xl7 = C(7,13)Xl3 + C(7,15)Xl5 8) Xl9 = C(8,12)Xl2 + C(8,27)X27 + C(8,28)X28 9) X20 = C(9,5)X5 + C(9,12)Xl2 + C(9,17)Xl7 + C(9,28)X28 10) X21 = C(l0,12)Xl2 + C(l0,27)X27 + C(l0,28)X28 lJ) X22 = X5 + Xl2-Xl3 + Xl7-Xl9-X20-X21 + X27 + X28 + C(ll,3l)X31 12) X24 = X21 = C(l2,22)X22 + X23-X25-X26, when FC~1in$X24-s;:FC X24 = FCMin' when X24 < FCMin X24 = FC, when X24 > FC -90- 13) X25 X25 = X21 + C(l3,22)X22 + X23 -X24 -X26, when X24 ~ FCM. 1n = PET, when X24<FCM. 1n 14) X26 = C(l4,2l)X21 + C(l4,22)X22 + C(l4,23)X23 + C(l4,32)X32 C(l4,32) = RE(X24-FC) when X24>FC, otherwise C(l4,32) = 0 15) X29 = X28 (Dummy Equation) 16) X31 = Xl -X2 -X3 + X4 + X6 -Xll + Xl8 -Xl9 + X27 + X28 CALIBRATION PROGRAM AND NEW SUBROUTINES Although the calibration program used in the Yellowstone Impact Study was essentially the same as the one prepared by the Montana Water Resources Research Center (Boyd and Williams 1972), the program was modified to make the logic less dependent on the basin parameters. In the original version of the modeJ,basin parameters were fed into the main program and the program was run. If the model was used for some other basin with different parameters, the corresponding changes would have had to be incorporated and the whole program would have had to be run again. Three subroutines--INITIA, EXPORT, and SURFAC--were added and one subroutine--COMPUT--was modified in order to make the logic less dependent on the basin parameters. The result was an essentially data and basin independent calibration program that could be easily used on all nine subbasins. Figure 6 shows the hierarchy of the subroutines and their relationship to each other. These subroutines were called from left to right. Figure 6. Calibration program subroutines A brief description of the new subroutines is given below. INI TIA The initial values for different subbasins could be read either through changes in the subroutines or from the data card. In the original program, the following initial values were specified in the main logic, and the whole program was compiled and run. If the initial values changed, the original program had to be recompiled. The initial values specified were: 1) Initial precipitation for averaging precipitation (SAVE); -91- 2) Field capacity (FC) and minimum field capacity (FCM. ) ; l.n 3) Coefficients for moving average rainfall ( Q) ; 4) Beginning year and ending year ( 1'1, N); and 5) Number of months ( NP). Since these values could be read outside the main program, the rest of the revised program was subbasin independent. With this idea in mind, the sub- routine INITIA was created. The values that were read into INITIA are: 1) 2) 3) 4) 5) 6) 7) 8) 9) SAVE--initial precipitation for averaging; FC, FCM. --field capacity, minimum field capacity; l.n a--precipitation averaging factor; ;.J,N--beginning and ending year; Rl,Pl--coefficients for calculating X7 (ground-water outflow); R2,P2--coefficients for calculating XB (ground-water inflow); RE--groundwater recharge factor (ground-water recharge due to saturation of field capacity); NP--number of months for study period; and MP--number of months for calibration. In most cases, the number of months for study period should be the same as for calibration, however, if calibration is for a shorter period MP would be different from NP. Note that the subroutine INITIA has coefficients for calculating X7 (ground-water outflow) and XB (ground-water inflow). The following relation- ships were used to calculate X7 and X8: X7 = (Pl)(Xl) + Rl XB = (P2)(X2) + R2 where: Xl = outflow from the basin X2 = inflow to the basin Since Xl and X2 were primary values (i.e., they were read in as an input to the system) X7 and XB could also be read in as primary values because of the above relationships. !n the original program, X7 and XB were a part of the system of equations. This increased the matrix size. As mentioned above, X7 and XB did not need to belong to this system of equations, since their values were known as soon as -92- I } I . Xl and X2 were known. This feature was exploited in reducinQ the mntrix size. With the addition of INITIA in the program, X7 and XB are calculated right after Xl and X2 are read. EXPORT This subroutine was added to handle exports from the subbasin. The export variable 5(27) may, at times, have depended on the month NM. In case that export was zero, S(27) = 0 for all NM. (NM = month considered.) SURFAC In the original calibration program, evaporation loss from the reservoir was calculated as a certain percentage of the storage. More accurate evapora- tion losses may be calculated by multiplying the pan evaporation coefficient by surface area. When the daily pan evaporation coefficient was available, there was no need for any correction, such as for wind or humidity. l~ultiplyinq the pan evaporation coefficient by the surface area.gives a fairly accurate estimate of evaporation losses. Since the unit of time for the study was one month, the average pan evaporation coefficient value for the month could be used without any correction factor. This subroutine could take 36 storage levels in some uniform steps. The actual surface are~ was interpdlated linearly between two adjacent levels. COMPUT In the original program, snowfall had been treated as a part of the system of equations. Since snowfall is a function of precipitation and temperature, both of which are known, snowfall could be calculated outside the system of equations. The COMPUT subroutine was modified to calculate snowfall. Other than this change, this subroutine was essentially the same as the original subroutine. SIMQUAL--THE SIMULATION PROGRAM Although SIMQUAL, as the modified simulation program was named, retained the basic character of the original SWP model, SIMQUAL contained some new features which included water quality calculations, changes in the output format, and different criteria for the operation of reservoirs. The SIMQUAL program had many new subroutines compared to the original SWP program (Montana University 1972). Figure 7 shows the hiemrchy of SIMQUAL's subroutines. -93- Figure 7. Simulation program subroutines Subroutines DEPLET, COMPUT, SURFAC, EXPORT, INITIA, and QUALTY were sub- basin dependent; all others were subbasin independent. Subroutines common to the simulation and calibration programs (those which occur both in figure 6 and in figure 7) remained essentially the same except COMPUT. Changes in the COMPUT subroutines were due to rearrangement of the system of equations. The new subroutines are described briefly. DEPLET This subroutine, added to the main program, handled any reallocation of water as between two states or regions. As an example, for the Yellowstone Impact Study, inflows from the Tongue River, the Powder River, or the Bighorn River had to be reduced to allow for Wyoming's share of ~ater from these rivers. The amount to be allocated was based on the compact between the two states. As the name implies, this subroutin~ allowed for this depletion. During the simulation phase, any changed inflow to the subbasin may be read in1 the sub- routine DEPLET. Arguments of the subroutines are month IT and inflow 5(2). SURFAC Subroutine SURFAC calculated the evaporation loss from a reservoir based on the surface area of the reservoir and the pan evaporation coefficient for that month. It is assumed that the average value of a pan evaporation co- efficient for each month will takP. into account factors such as temperature, humidity, and wind on an average basis. -94- INITIA This subroutine defined the initial values of some of the By creating this subroutine, the main program became independent of the subbasin and scenarios. MODIST MODIST was a short form of monthly distribution, ranking the data on a monthly basis and finding ninetieth p~rcentile and median values (i.e. flows that are exceeded in 90 percent of those months and 50 percent of those months, for a particular month). It also calculated the mean value on a monthly basis. For ranking the data, subroutines SORT and COMPAR were called. Subroutine PLOT was called to plot the ninetieth percentile and fiftieth percentile values. Arguments of the subroutine were NMO, AA, and YY. AA corresponds to monthly data, NMO is number of months, YY, if zero implies water quality year, otherwise water year. QUAL TV This subroutine was called by the OUTPUT subroutine to calculate total dissolved solids (TDS) based on outflow. Arguments of the subroutine QUALTY were Q, RF, DIV, EN, OF, IT, TDS, TDSF, TDSQ, TDSL, TDSLl, TDSFl, TDSL2, and TDSF2 where: Q = outflow or release; RF = return flow; DIV = diversion requirement (irrigation plus energy and instream flows); EN = energy flow; OF = outflow RF plus instream plvs spill; and IT = counter on month. These arguments, required for TDS calculations, were transferred back to the OUTPUT routine for further calculations and output. TDS calculations are shown schematically in figure 8. -95- I Q, TDSI II (Outflow from the model) I jQUD, LUDj fqrR, LIRl IOEN, LEN! I QUD QRET ll_~c_D~_:> ______ --QEN I QUD + QRET, LUD + LIR QCONS + QEN, LEN (salts contained in out flow) (salts lost from the system) where: Q = net outflow = QUD + QIR + QEN QUD = undiverted water in million acre-feet QIR = diverted irrigation water in million acre-feet = QRET + QCONS QRET = return flow in million acre-feet QCONS = consumptive use of diverted irrigation water in million acre-feet QEN = energy plus consumptive industrial water LUD, LIR, LEN = total dissolved solids in tons in QUD, QIR, and QEN, respectively. Figure B. Schematic representation of TDS calculations. Figure 8 shows that the total salt lost from the system was due to industrial or energy water. Salts in the irrigation diversion were assumed to come back to the mainstem through return flow. Thus the outflow was QUD + QRET with total load of LUD + LIR. TDS was calculated using a monthly regression equation: TDS = f(Q,c) where: Q = flow in million acre-feet; c = a constant; and f = a function giving the relationship between TDS and (Q,c) -96- LUD = TDSI(QUD LIR = TDSI ( QIR) LEN = TDS I( QEN) Outflow TDSI = LUD + LIR QUD + QRET In addition to finding the outgoing quality, the following quantities were also calculated in this subroutine: 1) Total load diverted in tons for irrigation, TDST: 2) TDS in parts per million, TDS(ll); 3) Outgoing load in tons, TDSL(II); 4) Outgoing TDS, TDSF(ll); 5) Total load in the stream TDSQ(II); 6) Total outgoing load with half ton/acre salt pick up, TDSLl(Il); 7) Total outgoing load with one ton/acre salt pick up, TDSL2(II); and 8) TDSFI(II), TDSF2(II) outgoing water quality with half-ton and one-ton salt pick up per acre, respectively. Water quality calculations were based on yearly intervals extending from April through March, whereas other calculations were based on the water year which extends from October through September. Consequently, the first six months and the last six months of the thirty-year study period were ignored in water quality calculations. The total load in tons that was diverted for irrigation is from April through October. This diverted load returned to the stream during the same year--April through March--with the distribution shown in table 46. Table 46. Percentage by month of TDS returning to ~treamflow. Apr. May June July Aug. Sept. Oct. Nov. Dec. Jan. Feb. Mar. 11% 14% 18% 18% 4% -97- The subroutine QUALTY was called after every simulated twelve months. This was mainly due to different amounts of salt load in the stream from one year to the next. PRINT This subroutine was primarily meant for printing headings on the monthly values of outflow, inflow, and water quality in TDS. Arguments of the sub- routine were AA, NMO, and YY. AA corresponded to monthly data, NMO to the number of months, and YY, if zero, implied water quality year (April through March), otherwise water year. MEAN This subroutine mainly calculated the simple average or time weighted average and volume weighted average of TDS. These averages were calculated by the month and also by the year. Arguments of the subroutine were NMO, AA, BB, and YY. AA contained TDS data and BB, the flow data. NMO and YY have the same meaning as defined above. SORT and COMPAR These subroutines were called by the MODIST subroutine for ranking the data in ascending order. PLOT Subroutine PLOT plotted the fiftieth and ninetieth percentile values (i.e. those values exceed 50 and 90 percent of the time) of outflow, inflow, and water quality. Arguments of the subroutine were NMO, AA, BB, SF, and YY. AA corresponded to fiftieth percentile data and BB represented ninetieth percentile data. SF was the scale factor and equaled 80 percent of the largest value of fiftieth percentile data; YY, if zero, implied water quality year, (April through March), otherwise water year. -98- TYPES OF SIMULATION When all subbasins had been calibrated, they were ready for simulation runs. An ideal model--for simulation is the one that allows a wide range of operating criteria to be used in each simulation. Unfortunately, most models can carry out simulations only over a given set of rules and a limited number of operating criteria. The swp model is no exception. In this study, the SWP was used to study three types of simulations. Type 1 In type 1 simulations, the operating rules were to release water from the reservoir to meet the minimum flow requirement, to keep storage as high as possible, but to give releases to maintain minimum flows a higher priority than storage. Under such conditions, the annual yield was the maximum amount of water that could be withdrawn from the reservoir for each year of the study period while maintaining a minimum storage level. Type 2 In type 2 simulations there was no storage in the basin and consequently what could not be used was lost from the system. The maximum amount of water that could be used was dictated by the minimum flows in the study period. Type 3 Type 3 simulations differed from type 1 in the operating policy. The operating policies were to release wat~r from the reservoir to give the irri- gation demand highest priority and always satisfy that demand (d), and to store water in the dam if the inflow to the dam exceeded the demand plus the reservations for minimum flows. If the inflow was less than the demand d, thenthe flow was augmented by the release from the dam to meet the demand d. If the inflow was less than 6 + d, where n is the minimum required flow, but more than d, then nothing could be stored and inflow was passed through the dam. If inflow exceeded n + d, the excess inflow over n + d could be stored, if storage space were available. The simulation program as written by Boyd and Williams (1972) was useful for type 1 simulations. The main logic of the program had to be modified to include type 3 simulations. Besides changing the logic, the simulation program was modified to include water quality calculations based on total dissolved solids ( TDS) • -99- ;I :I SCENARIOS Each subbasin had up to three scenarios for simulating high, inter- mediate, and low water use. In each scenario the demands for irrigation, energy, and municipal use were lumped together. The model in this form did not discriminate among the demands explicitly based on their use; however, it discriminated among them indirectly whenever necessary. For example, if the total demand for irrigation, energy, and municipal water could not be satisfied for the period of study, then the program assumed that the irri- gation and municipal demands had a higher priority than the energy demand. Satisfying the ir~igation and municipal demands implied that although all of the irrigation and municipal demands could be satisfied, there would not be enough water to meet all of the energy demand. The same model could be run satisfying part of the energy demand. Finding the demand that could be satisfied was essentially the same as finding the yield of the subbasin. Since the quality of water leaving the subbasin was a function of irrigation diver- sion return flows, it was important to identify the satisfied demands. For subbasins that had no reservoir, the portion of the logic for storing water was eliminated and other portions of the program were changed. In type 3 simulations, the data were arranged in a different way. For example, suppose that the total demand for irrigation plus energy, municipal, and instream requirements is d and the minimum flow demand is 6. As per the operating rule, water can be stored if the inflow exceeds b + d. The dam can release water to meet d, but can release no water to augment the flows for the minimum flow requirement. The demand d is read in as RA(I) in the program and d + 6 is read in as FG(I). The decision to store or to release water is de- termined by the inflow. If the inflow exceeds FG(I), water can be stored. The amount to be stored will depend on the storage level. In case the inflow is between RA(I) and FG(I) there would be no need to augment the flows since demand RA(I) would be satisfied. Water would not be stored because the inflow is less than FG(I). For inflows less than RA(I), flows would be augmented to meet demand RA(I). The main consequence of the above mentioned operating rule was the reduction in the yield of the subbasin, because the reservoirs were not allowed to store as much as they could. In simulation, the system of equations used was exactly the same as used in calibration with the exception of the role played by the following equation: X31 = Xl -X2 -X3 + X4 + X6 + Xll + XlB -Xl9 + X27 + X28 The above equation was used for solving for X31 in the calibration phase, but in the simulation this was used for solving for Xl or X4. Xl = X2 + X3 -X4 -X6 -Xll -XlB + Xl9 -X27 -X28 + ·x31 or X4 = Xl + X2 + X3 -X6 -Xll -Xl8 + Xl9 -X27 -X28 + X31 An implicit assumption in this logic is that the demand d has higher priority than the minimum flow demand, but this can be changed if necessary. I -100- Thus, by interchanging the role of XI nr X4 with X31, the same equati~n could be used in simulation. When the above equation was used for solving for XI, the set of equations was said to be in mode 1. When solving for X4, it was said to be in mode 4. The equations for the simulation follow: 1) XI = X2 + X3 -X4 -X6 -Xll -XlB + Xl9 -X27 -X28 + X31 2) X6 = C(2,2)X2 + C(2,19)Xl9 + C(2,28)X28 + C(2,3l)X31 + C(2,32)X32 3) XlO = X7 -XB + X9 -Xll + Xl2 -X26 4) Xll = C(4,2)X2 + C(4,3)X3 + C(4,4)X4 + C(4,19)Xl9 + C(4,28)X28 + C(4,3l)X31 5) Xl2 = C(5,9)X9 + C(5,10)Xl0 + C(5,32)X32 6) Xl4 = C(6,15)Xl5 + C(6,16)Xl6 7) Xl6 = Xl3-Xl4 + Xl5-Xl7 + XlB + C(7,22)X22 + C(7,3l)X31 8) Xl7 = C(B,l3)Xl3 + C(B,l5)Xl5 9) Xl9 = C(9,12)Xl2 + C(9,27)X27 + C(9,28)X28 10) X20 = C(l0,5)X5 + C(l0,12)Xl2 + C(l0,17)Xl7 + C(l0,28)X28 11) ~ X21 = C(ll;l2)Xl2 + C(ll,27)X27 + C(ll,28)X2B 12) X22 = X5 + Xl2 -Xl3 + Xl7 -Xl9 -X20 -X21 -X27 + X28 + C(l2,3l)X31 13) X24 = X21 + C(l3,22)X22 + X23- X25-X26 when FCMin~X24 ~ FC X24 = FCM. when X24 < FCM. 1n 1n 14) X24 = FC when X24 > FC X25 = X21 + C(l4,22)X22 + X23 -X24 -X26 when X24 < FCM. otherwise 1n X25 = PET 15) X26 = C(l5,2l)X21 + C(l5,22)X22 + C(l5,23)X23 + C(l5,32)X32 where: C(l5,32) = RE(X24 -FC) when X24 = FG, otherwise C(l5,32) = 0 16) X29 = X28 (Dummy equation). -101- .. Reordering of equations and coefficients was necessary becamse of the inverse subroutine used in the program. The logic was changed from mode 1 to mode 4 and vice versa, depending upon the storage condition. If the storage was full, the system was solved for outflow Xl, and hence mode 1, otherwise, in mode 4. AREA SIMULATIONS THE UPPER YELLOWSTONE, CLARKS FORK YELLOWSTONE, AND KINSEY AREA SUBBASINS These three subbasins were not simulated. Rather the projected water requirements for these subbasins for each of the three levels of development were merely subtracted from their historical outflow, so that the simulations for downstream subbasins would reflect all upstream water use in addition to their own. THE BILLINGS AREA SUBBASIN Inflow to the Billings Area Subbasin for a particular level of develop- ment was the sum of the outflows from the Upper Yellowstone and Clarks Fork Yellowstone subbasins for the same level of development. By using a similar procedure for each subbasin, the cumulative effect of development could be simulated for the lower subbasins in the Yellowstone basin. The water requirements for the low, intermediate, and high levels of development in the Billings Area Subbasin are shown in table 47. These re- quirements reflect only the water that would be needed to meet irrigation and municipal demands. None of the levels of development called for water to meet energy demands or minimum-flow requirements. For all three levels of development, flows would be neither augmented nor stored because the sub- basin has no dam to regulate flows. The results of the simulations of the three levels of development are shown in tables 48 and 49. The simulation indicated that the Billings Area Subbasin would have enough water to meet the demands of a high level of development, although the demands would reduce the flows in June, July, August, and September below their historical levels. The demands of the low and intermediate levels of development would not significantly reduce historical flows. Generally, none of the simulations indicated appreciable degradation of water quality although it is likely that the few low-flow months under the high level of development would result in a drastic-degradation in water quality. THE BIGHORN SUBBASIN Because of the presence of the Yellowtail Dam, the Bighorn Subbasin would meet its demands under high and intermediate levels of development. The low level of development was not considered for this subbasin because the water -102- requirements would be insignificant compared to the historical flow of the river. Table 50 shows the flow requirements for the intermediate and high levels of development. These flow requirements include energy, irrigation, and municipal demands but no minimum-flow requirements. In both levels of development, it was assumed that the Yellowtail Dam would be available to augment or store streamflows throughout the simulation period. A depletion allowance consistent with the Yellowstone River Compact was made in the Big- horn Subbasin's inflows. · · Table 47. Billings area subbasin water requirements (in acre-feet). Projected Level of Development Month Low ' Intermediate High Oct 485 685 905 Nov 290 295 325 Dec 290 295 325 Jan 290 295 325 Feb 290 295 325 Mar 290 295 325 Apr 485 685 905 May 2,815 5,240. 7,895 June 3,590 6,895 10,235, July 6,500 12 '715 18,955 Aug -5,140 10,000 14,880 Sept 2,425 4,565 6,730 TOTAL 22,890. 42,260 62,130 "'"::-,, The results of the simulations of the high and intermediate levels of development are shown in table 51. The demands of the high level of develop- ment would easily be satisfied without affecting natural· flows significantly, although the ninetieth-percentile flows (those flows exceeded 90 percent of . the time in a given month) would be low for July and August. This, however, was due to the operational policy used for the dam in the simulation. In any event, a release from the dam exceeded the requirement orily if it was a spill from the dam. Like the high level of development simulation, the intermediate level of development simulation indicated little effect on the natural outflow. In either case, the water quality of the outflow would remain almost unchanged from the natural outflow's water quality because the total demand for both simulations would be small compared to the natural outflow. Total dissolved solids would vary from 477 to 634 mg/1 for the intermediate level and from 477 to 650 mg/1 for the high, a small range due to the Yellowtail Dam which reduces fluctuations in water quality. -103- Table 48. Outflow of the Billings area subbasin (in acre-feet). Level of Development Low Intermediate High Fiftieth Ninetieth Fiftieth Ninetieth Fiftieth Ninetieth Month percentile percentile percentile percentile percentile percentile Oct 245,036 163,456 244,956 163,380 244,866 163,295 Nov 219,666 188,062 219,982 188,379 220,263 188,660 Dec 178,411 133,290 178,661 133,545 178,882 133,769 Jan 153,036 100,470 153,219 100,663 153,367 100,820 Feb 159,451 120,568 159,567 ]20,690 159,657 120,787 MHr 210,452 143,850 210,636 144,040 210,786 144,195 Apr 241,904 167,308 241,574 166,985 241,219 166,637 May 697,674 360,719 691,032 334,079 684,165 327,214 June 1 '545 ,894 1,065,127 1,537,069 1,056,308 1,528,209 1,047,449 July 804,278 379,376 787~143 362,245 769,993 345,099 Aug 230,954 119,876 217,809 106,737 204,654 93,589 Sept 184,038 108,507 178,382 102,850 172,690 97,157 NOTE: A fiftieth-percentile flow is the flow that is exceeded 50 percent of the time in a particular month, and the ninetieth-percentile flow is that flow that is exceeded 90 percent of the time in a particular month. Table 49. Average outflow (in acre-feet) and TDS (in mg/1) of the Billings area subbasin Level of Development · Low Intermediate High Natural Month Flow TDS Flow TDS Flow TDS Flow Oct 248,041 268 247,966 269 247,881 270 262,944 Nov 227,485 278 227 '776 279 228,059 279 227,424 Dec 173,022 305 173,270 306 173,488 306 173,048 Jan 15:3,559 312 153,747 312 153,900 313 153,655 Feb 167,798 289 167,916 289 168,009 290 167,954 Mar 222,461 267 222,650 268 222,803 268 222,558 Apr 249,442 253 249,117 253 248,768 254 253,506 May 688,842 156 682,185 156 675,321 157 746,377 June 1,565,048 117 1,556,220 117 1,547,358 118 . 1,636,944 July 830,338 131 813,202 132 796,052 134 932,201 Aug 252,659 228 239,513 231 226,358 235 344,169 Sept 199,550 283 193,892 286 188,199 289 263,177 TOTAL 4,978,245 4,927,454 4,876,196 5,383,957 -104- I t ; I· ,' ' i ,, Table 50. Bighorn subba~in water requirements (in acre-feet) Level of Development Honth Intermediate High Oct 750 2, 775 Nov 490 2,385 Dec 490 2,385 Jan 490 2,385 Feb 490 2,385 Mar 490 2,385 Apr 750 2,775 May 3,880 7,470 June 4,920 9,035 July 8,830 14,900 Aug 7,010 12,170 Sept 3,360 6,685 TOTAL 31,950 67,735 Table 51. Outflow (in acre-feet) and TDS (in mg/1) of the Bighorn Subbasin Level of Development Intermediate High Fiftieth Ninetieth Fiftieth Ninetieth Month Percentile Percentile Average TDS Percentile Percentile Average TDS Oct 194,045 140,169 197,372 625 188,241 134,252 191,535 627 Nov 184,077 142,153 184,734 ' 631 180,204 138,223 180,780 632 Dec 164,977 109,022 160,842 612 160,974 104,977 156,861 613 Jan 143,349 100,767 153,433 552 139,343 96,807 149,412 554 Feb 144,398 107,600 169,476 477 140,336 103,678 165,413 477 Mar 211,631 157,238 232,825 503 207,573 153,146 228,792 504 Apr 204,188 119,215 201,080 624 198,322 113,168 195,063 626 May 259,527 135,198 282,443 592 236,007 109,680 256,963 595 June 566,793 137,846 546,688 594 534,673 105,791 514,631 596 July 261,441 30,130 312,457 579 204,851 2,340 260,706 584 Aug 81,338 36,351 lll ,056 625 35,368 2,340 67,477 650 Sept 155,622 91,851 157,206 634 131,494 57,261 128,967 640 TOTAL 2,709,612 2,496,600 NOTE: See note to table 48. -105- THE MID-YELLOWSTONE SUBBASIN The water requirements for the low, intermediate, and high levels of development in the Mid-Yellowstone Subbasin are given in table 52. These re- quirements include demands for energy, irrigation, and municipal use but no minimum flow requirement. The Mid-Yellowstone Subbasin was assumed to have no ability to augment or store flows. Table 52. Mid-Yellowstone subbasin water requirements (in acre-feet) Level of Development Month Low Intermediate High Oct 3,320 6,950 12,700 Nov 3,070 6,445 11 '940 Dec 3,070 6,445 11,940 Jan 3,070 6,445 11,940 Feb 3,070 6,445 11,940 Mar 3,070 6,445 11,940 Apr 3,320 6,950 12,700 May 6,350 13,005 21,780 June 7,360 15,025 24,815 July 11,165 22,595 36,160 Aug 9,380 19,055 30,860 Sept 5,845 11,995 20,265 TOTAL 62,090 127,800 218,980 The fiftieth-and ninetieth-percentile outflow values for all simulated levels of development in the Mid-Yellowstone Subbasin are given in table 53. The ninetieth-percentile flows would be high for all months but August. Dur- ing the simulated month of August 1961, there was some shortage for both the intermediate and high levels of development; this was the only shortage indicated. The average values of TDS, displayed along with average flows in table 54, indicate that water quality would become slightly poorer during the simu- lated low flows of 1961, When the large proportion of irrigation return flow in the outflow substantially decreased water quality. THE TONGUE SUBBASIN Table 55 gives the water requirements for the Tongue River under the low, intermediate, and high levels of development. The "Projected Demand" columns show demands for irrigation, municipal use, and energy. At the high level of development, not all of the irrigation, municipal, and energy requirements could be satisfied. Since the irrigation and municipal demands have higher priority, only 4,435 acre-feet of the projected energy demand of 9,835 -106- acre-feet per month could be met. For the high level of development, the "Projected Demand" column also shows minimum-flow requirement judged by the Montana Fish and Game Department to be a "bare-bones" requirement: 900 acre- feet per month for June through February, 2700 acre-feet per month for March, April, and May. For the remaining two levels of development, the minimum-flow requirement is shown only in the second column. For the intermediate develop- ment level that minimum-flow requirement is 60 percent of the instream flow assumed by the Water Work Group of the Northern Great Plains Resources Program (NGPRP ]974); for the low level of development, all of the NGPRP-assumed instream flow was included. A reservoir with a capacity of 320,000 acre-feet was assumed for the high and intermediate levels of development, and a reservoir with a capacity of 112,000 acre-feet was assumed for the low level of develdp- ment. Table 53. Outflow of the Mid-Yellowstone subbasin (in acre-feet) Level of Development Low Intermediate High Fiftieth Ninetieth Fiftieth Ninetieth Fiftieth Ninetieth Month Percentile Percentile Percentile Percentile Percentile Percentile Oct 462,205 323,536 459,151 320,492 448,648 310,188 Nov 409,310 333,575 406,677 330,930 398,081 322,045 Dec 337,255 217,102 334,446 214,307 325,382 205,456 Jan 296,842 194,918 293,910 191,983 284,947 182,934 Feb 302,286 225,893 299,204 222,809 290,037 213 '586 Mar 388,389 294,533 485,442 291,594 476,136 282,481 Apr 465,915 326,058 462,291 322,432 451,155 311 '278 May 988,032 439,194 975,673 426,837 935,515 386,800 June 2,129,436 1,175,717 2,114,182 1,160,467 2,064,900 1,111,223 July 1,080,117 408,825 1,053,213 381,985 968,080 325,307 Aug 305,904 142,989 284,700 121,804 215,827 64,785 Sept 342,057 210~790 331,134 199,867 291,202 137,652 NOTE: See note to table 48. The fiftieth-and ninetieth-percentile flows for the three simulations are given in table 56. The 320,000 acre-foot reservoir used in the intermediate- and high-level simulations could satisfy a total annual demand of about 130,000 acre-feet. The fiftieth-and ninetieth-percentile values would be almost equal for those two levels of development, implying that the outflow consisted only of the irrigation return flows plus instream requirements. -107- Table 54. Average outflow (in acre-feet) and TDS (in mg/1) of the Mid-Yellowstone subbasin Level of Development Low Intermediate High Natural Month Flow TDS Flow TDS Flow TDS Flow Oct 460,062 460 457,015 460 446,660 465 478,565 Nov 417,964 486 415,323 486 406,554 490 423,122 Dec 323,390 558 320,589 558 311,654 562 341,435 Jan 300,485 476 297,545 576 288,413 581 318~323 Feb 344,890 529 341,800 529 332,483 532 368,217 Mar 493,392 441 490,452 441 481,304 443 493,009 Apr 456,588 462 452,962 462 441,822 467 466,004 May 941,441 311 929,090 313 889,073 320 1,013 '584 June 2,103,569 198 2,088~318 201 2,039,064 203 2,164,446 July 1,166,987 269 1,140,055 271 1,059,693 280 1,326,683 Aug 359,878 504 338,680 508 272,129 530 501,157 Sept 362,990 524 352,061 529 310,895 556 442,866 TOTAL ·7,731,636 7,623,890 7,279,744 8,337,411 Table 55. Tongue subbasin water requirements (in acre-feet) Level of Development Low Intermediate High Projected Projected Demand Projected Projected Demand Projected Month Demand Plus Minimum Flow Demand Plus Minimum Flow Demand -Oct 1,175 7,175 4,370 7,970 6,000 Nov 955 6,955 3,930 7,530 5,400 Dec 955 9,055 3,930 8,790 5,400 Jan 955 9,055 3,930 8,790 5,400 Feb 955 9,055 3,930 8,790 5,400 Mar 955 12,995 3,930 11,130 5,400 Apr 1,175 14,975 4,370 12,650 6,000 ~1ay 3,810 29,310 9,335 24,935 13,960 June 4,685 30,185 11,390 26,690 16,595 July 7,985 30,185 17,975 31,300 26,470 Aug 6,445 12,445 14,900 18:500 21,860 Sept 3,370 9,370 8,760 12,360 12,645 TOTAL 33,420 180,760 90,750 179,435 130,530 -108- Table 56. Outflow of the Tongue River subbasin (in acre-feet) . Level of Development Low Intermediate High Fiftieth Ninetieth Fiftieth Ninetieth Fiftieth Ninetieth Month Percentile Percentile Percentile Percentile Percentile Percentile Oct 6,585 1,562 4, 770 1,170 2,655 2,655 Nov 6,365 4,943 4,335 2,338 1,997 1,997 Dec 8,390 5,667 5,665 2,862 1,778 1 '778 Jan 8,320 1:319 5,300 4,624 l,ss8 1,558 Feb 8,245 5,834 5,150 2,745 1,339 1,339 Mar 23,812 12,260 7,640 7:640 3,358 3,358 Apr 23,129 11,375 8,860 5,133 3,578 3,578 May 44,807 15,337 17,205 9,237 5,113 5,113 June 103,865 4,479 57,310 2,045 40,320 3,472 July 13,994 1,315 2,630 2,630 4,849 4,845 Aug 1,315 1,315 2,630 2,630 4,849 4,849 Sept 6,730 730 4,182 1,460 3,094 3,094 NOTE: See note to table 48. Table 57. Average outflow (in acre-feet) and TDS (in mg/1) of the Tongue subbasin Level of Development Low Intermediate High Natural Incoming Month Flow TDS Flow TDS Flow TDS Flow TDS Oct 9,078 516 4,567 752 2,744 779 16,995 607 Nov 9,832 670 4,816 766 2,261 793 18,369 696 Dec 9,964 739 5,514 798 2,080 835 12,893 756 Jan 10,496 675 5,609 753 2,168 768 11 '092 719 Feb 16,584 412 8,740 464 3,992 494 16,414 491 Mar 40,952 416 26,354 432 20,830 422 39,248 431 Apr 27:936 542 18,732 560 14,194 555 32,325. 550 May 51,155 440 36,080 470 26,765 464 48,955 443 June 101,622 262 76,818 283 65,115 285 95,469 265 July 18,857 381 11,263 517 8,453 562 30,657 348 Aug 2,589 857 2,869 1,137 4,849 768 9,397 423 Sept 6,391 597 3,700 785 3,094 752 12,167 507 TOTAL 305,456 205,062 156,545 343,981 -109- Table 57 gives the values of average outflows and levels of TDS for each level of development in the Tongue Subbasin. Under the low level of develop- ment; water quality calculations showed only slight degradation. Under the intermediate level of development, TDS calculations indicate a slight de- terioration in water quality. Because most of the outflow during August would consist of irrigation return flows, that month would have the worst water quality. At the high level of development, TDS levels indicate poor water quality in most months, a result of what would be reduced outflow having a large proportion of irrigation return flows. lnstream flows would be crucial in maintaining water quality. By increasing the instream requirement, water quality degradation could be reduced, especially in low-flow months. Under the low level of development, the irrigation, municipal, and energy demand as well as all of the NGPRP-requested minimum flow could be completely satisfied, even assuming the smaller reservoir. The fiftieth-and ninetieth- percentile values (table 56) indicate that August would be the only critical month at this level of development. For the intermediate level of development, the total water demand was about 91,000 acre-feet. As explained above, the 320,000-acre-foot reservoir would yield 130,000 acre-feet annually, leaving 40,000 acre-feet per year available for other uses. Up to 60 percent of the minimum flow suggested by the NGPRP could be satisfied with this water. This minimum flow would not be augmented by releases of stored water from the dam. If the natural inflow to the reservoir is less than or equal to the minimum-flow requirement, then no water could be stored. If the natural inflow is more than the minimum-flow requirement, then the excess could be stored or used to meet the "projected demand" of table 55. In either case, stored water could be released to meet ·projected consumptive demand. The fiftieth-and ninetieth-percentile flow values show that, except in July and August, there would be water in the stream in addition to the return flows. THE POWDER SUBBASIN Table 58 gives the water requirements used in simulations of the Powder Subbasin. The high level of development called for 230,000 acre-feet for irrigation water alone; the assumed active storage in the subbasin was only 275,000 acre-feet. After five trial simulations, it became apparent that not all of the water demand of the intermediate and high levels of development could be satisfied. Instead, those two projected levels of development were replaced by the "55 percent" level, which consisted of 55 percent of the high- level irrigation demand, the full high-level municipal demand and no water for energy or for minimum-flow requirements. Nor were minimum-flow requirements considered for the low level of development. -110- Table 58. Powder subbasin water requirements (in acre-feet) Level of Development Month Low 55 Percent Oct 820 1,335 Nov 70 95 Dec 70 95 Jan 70 95 Feb 70 95 Mar 70 95 Apr 820 1,335 May 9,850 16,225 June 12,855 21,185 July 24,140 39,800 Aug 18,870 31,115 Sept 8,345 13,745 TOTAL 76,050 125,215 The simulation recognized Wyoming's 42-percent share of the Powder River's water by including only 58 percent of the historical inflows' values in the simulation, with the exception that in no month were the historical inflows' values reduced by more than 7,140 acre-feet (42 percent of 17,000 acre-feet) regard~ess of the size of the historical monthly flow. The annual yield of the subbasin was calculated assuming a reservoir having a yield of 125,000 acre-feet. This yield was based on the assumption that the reservoir's inflow included flows from the Little Powder River, an impossibility at the.Moorhead site, which is the most probable location for the reservoir. The 125,000-acre-foot yield might be achieved if two dams were built, one on the Little Powder and one on the Powder. The_results of the simulations are given in table 59. If a dam were built, the water quality of the river below the dam would be changed. Seasonal variations in water quality would be averaged, resulting in a net improvement in water quality. The amount of improvement is unknown. Even at the low level of development the irrigat~on demand would be 76,000 acre-feet, a third of which would come back to the river as return flo"w. TDS levels would range from 1,000 to 3,400 mg/1. Mixing in the reservoir could achieve substantial improvement in water quality. At this level of development, the fiftieth-and ninetieth-percentile values were the same for most months, meaning that the outflow would consist mostly of the return flows from irrigation. The average flows for each month, however, would be much higher than the fifti- eth-percentile flow, showing the variability in the flow of the river. -111- Table 59. Outflow (in acre-feet) and TDS (in mg/1) of the Powder subbasin Level of Development Low 55 Percent Fiftieth Ninetieth Fiftieth Ninetieth Month Percentile Percentile Average TDS Percentile Percentile Average TDS Oct 2,000 2,000 5,856 2,079 3,000 3,000 3,363 3,799 Nov 1,250 1,250 6,542 1,630 1,800 1,800 2,706 3 '22'6 Dec 1,000 1,000 4,673 1,937 1,500 1,500 2,356 3,216 Jan 750 750 4,257 1,976 1,130 1,130 2,085 3,000 Feb 2,982 500 13,043 1,036 750 750 6,136 1,402 Mar 34,922 750 61,954 739 1,130 1,130 46,946 750 Apr 30,600 3,315 43,997 1,061 19,797 1,500 30,941 1,149 May 51,484 16,066 55,376 1,096 31,586 4,040 38,324 1,310 June 84,438 3,500 102,888 1,028 63,416 5,260 89,507 1,116 July 4,500 4,500 20,483 1,552 6,760 6,760 14,383 3,372 Aug 4,500 4,500 4,970 3,548 6,760 6,760 6,760 8,089 Sept 2,500 2,500 3,667 3,145 3,760 3,760 3,760 4,084 TOTAL 327,706 247,267 NOTE: See note to table 48. In the 55 percent simulation, the outflows would consist mostly of irriga- tion return flows. The fiftieth-percentile flows would be high in the months of April, May, and June due to spring runoff and snowmelt in the upper portion of the basin. All ninetieth-percentile flows would be irrigation return flows. The irrigation projected for the 55 percent level would drastically degrade the water quality at the mouth of the river. The average TDS of inflows would be 1,200 mg/1, while that of the outflows would range from 1,100 to 4,000 mg/1 in most months. Again, however, mixing in a reservoir could reduce TDS loads significantly. THE LOWER YELLOWSTONE SUBBASIN The water requirements projected for the levels of development are given in table 60. demands for irrigation, energy, and municipal specified. high, intermediate, and low These requirements include use. No minimum flow was Inflow to the Lower Yellowstone Subbasin would be the sum of the outflows of the Powder and Kinsey Area Subbasins. Because no reservoir was assumed for the Lower Yellowstone Subbasin, the flows could not be stored or augmented. -112- Table 60. Lower Yellowstone subbasin water requirements (in acre-feet) Level of Development Month Low Intermediate High Oct 410 785 2,255 Nov 30 30 1,125 Dec 30 30 1,125 Jan 30 30 1,125 Feb 30 30 1,125 Mar 30 30 1,125 Apr 410 785 2,255 May 4,930 9,825 15,815 June 6,430 12,840 20,335 July 12,080 24,135 37,290 Aug 9,450 18,860 29,380 Sept 4,180 8,320 13,555 TOTAL 38,040 75,700 126,510 The results of the simulations are shown in table 61 and 62. The fiftieth-and ninetieth-percentile flows under all levels of development indicate that the demands could be satisfied but that a shortage would occur when demand exceeded inflow. A shortage would have occurred in August 1961 for all levels of development. The intermediate level of development would have less impact on flows than would the high level of development and the low level of develop- ment would have no significant impact. TDS concentrations would increase, but even under the high level of development, average water quality would remain relatively good due to the high flows during periods of large irrigation return flows. During months of low flows, water quality-degradation would be greater. The simulations for the Lower Yellowstone Subbasin are important in that they represent the effect of all projected development in the Yellowstone Basin. The annual average outflow of the Lower Yellowstone Subbasin for the low, inter- mediate, and high levels of development would be 7,731,626 acre-feet, 7,623,890 acre-feet, and 7,279,803 acre-feet, respectively. The average annual outflow, 1944-73, was 8~317,411 acre-feet. On the average, there would be enough water to satisfy the projected demand, but in some months of some years there would not be enough even for low-level development, as indicated by the · simulated shortage in August 1961. -113- Table 61. Outflow of the lower Yellowstone subbasin (in acre-feet) Level of Development Low Intermediate High Fiftieth Ninetieth Fiftieth Ninetieth Fiftieth Ninetieth Month Percentile Percentile Percentile Percentile Percentile Percentile Oct 453,165 305,608 450 '778 305,093 437,762 294,921 Nov 441,005 340,600 422,969 337,869 410,592 325,594 Dec 350,824 234,670 339,545 231,366 325,177 217,052 Jan 316,982 201,851 301 ,5B9 198,777 295,093 183,233 Feb 338~537 249,182 329,219 243,590 313,099 228,098 Mar 612,714 304,539 512,839 296,179 574,039 279,314 Apr 538,938 388,858 513,823 363,422 496,380 346,372 May 1,037,764 480,471 1,001 '548 440,103 953,657 387,916 June 2,217,203 1,123,425 2,155,473 1,101,047 2,091,092 1,051,323 July 1,085,902 393,907 1,049,411 358,134 961,489 296,861 Aug 353,761 138 '179 323,394 109,601 251,367 48,601 Sept 326,062 174,059 309 '139 160~003 266,401 98,503 NOTE: See note to table 48. Table 62. Average outflow (in acre-feet) and TDS (in mg/1) of the lower Yellow- stone subbasin Level of Deve~opment Low Intermediate High Natural Month Flow TDS Flow TDS Flow TDS Flow Oct 466,078 552 459,071 561 445,522 570 504,187 Nov 439,383 577 429,514 585 417,049 594 452 '667 Dec 339,180 636 331,424 640 317,270 646 354,445 Jan 321,902 648 314,522 653 299,309 664 342,515 Feb 377,602 565 363,556 572 346,679 579 396,331 Mar 652,078 496 613,719 504 . 607,521 508 707,417 Apr 588,151 538 564,206 544 547,420 548 617,821 May 988,728 368 943,250 377 893,574 386 1,050,604 June 2,304,475 291 2,240,210 291 2,186,485 291 2,379,886 July 1,231,810 304 1,179,48B 307 1,091,427 313 1,420,334 Aug 384,481 451 353,74B 458 284,934 482 483,946 Sept 345,388 557 327,167 566 282,328 583 426,303 TOTAL 8,439,256 8,119,875 7,719,518 9 '136 ,456 -114- -115- ! ~ \ 1 1. ' ,. . ~r I"• f: ~-: .. ~; ~·~· l\ A-1 A-2 PROJECTED WATER REQUIREMENTS IN THE YELLOWSTONE RIVER BASIN IN THE YEAR 2000 TABLES Monthly and annual water requirements in the upper Yellowstone subbasin, year 2000, under three levels of development Monthly and annual water requirements in the Clarks Fork Yellowstone subbasin • • • • • • • • • • • • • A-3 Monthly and annual water requirements in the Billings area subbasin • • • • • • • • • • • • • • • • • • • • A-4 Monthly and annual water requirements in the Bighorn subbasin to year 2000 under three levels of development • • • • • A-5 Monthly and annual water requirements ~n the Mid-Yellowstone sub~ basin to year 2000 under three levels of development . . . . A-6 Monthly and annual water requirements in the Tongue subbasin to year 2000 under three levels of development . . . A-7 Monthly and annual water requirements in the Kinsey area subbasin to year 2000 under three levels of development . . . . . A-8 Monthly and annual water requirements in the Powder subbasin to year 2000 under three levels of development . . . . . . A-9 Monthly and annual water requirements in the lower Yellowstone subbasin to ·year 2000 under three levels of development . . -117- PAGE 118 119 120 121 . 122 . 123 124 125 126 TABLE A-1. Monthly and annual water requirements in Upper Yellowstone subbasin, year 2000 under three levels of development (af). ENERGY IRRIGATION MUNICIPAL TOTAL Divert Deplete Divert Deplete Divert Deplete Divert Deplete LOW-LEVEL DEVELOPMENTb Jan Feb Mar Apr 380 250 380 250 May 4,950 3,300 4,950 3,300 Jun 6,470 4,315 6,470 4,315 Jul 12,180 8,125 12,180 8,125 Aug 9,520 6,350 9,520 6,350 Sep 4,190 2,790 4,190 2,790 Oct 380 250 380 250 Nov Dec ANNUAL 38,070 25,380 38,070 25,380 INTERMEDIATE-LEVEL DEVELOPt1ENTc Jan Feb Mar Apr 760 510 760 510 May 9,900 6,600 9,900 6,600 Jun 12,950 8,630 12,950 8,630 Jul 24,370 16,250 24,370 16,250 Aug 19,040 12,695 19,040 12,695 Sep 8,380 5,585 8,380 5,585 Oct 760 510 760 510 Nov Dec ANNUAL 76,160 50,780 76,160 50,780 HIGH-LEVEL DEVELOPMENTd Jan Feb Mar Apr 1,140 760 1,140 760 May 14,850 9,900 14,850 9,900 Jun 19,420 12,950 19,420 12,950 Jul 36,560 24,370 36,560 24,370 Aug 28,565 19,040 28,565 19,040 Sep 12,565 8,380 12,565 8,380 Oct 1,140 760 1,140 760 Nov Dec ANNUAL 114,240 76,160 114,240 76,160 aThe irrigation diversion rate is 3 acre-feet/acre; the depletion rate is 2 acre-feet/acre. bAssumptions: (no energy development); (12,690 acres of new irrigation)e; (negligible increase in population.) cAssumptions: (no energy development); (25,390 acres of new irrigation)e; (negligible increase in population). dAssumptions: (no energy development); (38,080 acres of new irrigation)e; (negligible increase in population). eirrigation is assumed to be developed with loans at 10 percent amortized over 10 years. -118- I ·I :,l >' .·• ~ ; ~:. ·~ .. ~ " :'1 '1 TABLE A-2. Monthly and annual water requirements in Clarks Fork Yellowstone subbasin, year 2000 under three levels of development (af). ENERGY IRRIGATIONa MUNICIPAL TOTAL Divert Deplete Divert Deplete Divert Deplete Divert HIGH-LEVEL DEVELOPMENTb Jan Feb Mar Apr 65 40 65 May 840 560 840 Jun 1,100 735 1,100 Jul 2,080 1,385 2,080 Aug 1,620 1,085 1,620 Sep 710 475 710 Oct 65 40 65 Nov Dec ANNUAL 6,480 4,320 6,480 Deplete 40 560 735 1,385 1,085 475 40 4,320 NOTE: The assumptions for both the low and intermediate levels of development were that there would be a negligible increase in energy development, population, and number of acres irrigated. Therefore, the amount of water depletion would also be negligible and is not shown. aThe diversion rate for irrigation is 3 acre-feet/acre; the depletion rate is 2 acre-feet/acre. bAssumptions: negligible increase in energy development, population; irrigate 2,150 new acresc. cAssumptions: , irrigation to be developed with loans at 10 percent amortized over 10 years. -119- TABLE A-3. Monthly and annual water requirements in Billings Area subbasin, year 2000 under three levels of development (af) ENERGY IRRIGATION 8 MUNICIPAL TOTAL Divert Deplete Divert Deplete Divert Deplete Divert Deplete LOW-LEVEL DEVELOPMENTd Jan 580 290 580 290 Feb 580 290 580 290 Mar 580 290 580 290 Apr 195 130 580 290 775 420 May 2,525 1,680 580 290 3,105 1,970 Jun 3,300 2,200 580 290 3,880 2,490 Jul 6,210 4,140 580 290 6,790 4,430 Aug 4,850 3,235 580 290 5,430 3,525 Sep 2,135 1,425 580 290 2,715 l '715 Oct 195 130 580 290 775 420 Nov 580 290 580 290 Dec 580 290 580 290 ANNUAL 19,410 12,940 6,960 3,480 26,370 16,420 INTERMEDIATE-LEVEL DEVELOPMENTe Jan 590 295 590 295 Feb 590 295 590 295 Mar 590 295 590 295 Apr 390 260 590 295 980 555 May 5,045 3,365 590 295 5,635 3,660 Jun 6,600 4,400 590 295 7,190 4,695 Jul 12,420 8,280 590 295 13,010 8,575 Aug 9,705 6,470 590 295 10,295 6,765 Sep 4,270 2,845 590 295 4,860 3,140 Oct 390 260 590 295 980 555 Nov· 590 295 590 295 Dec 590 295 590 295 ANNUAL 38,820 25,880 7,080 3,540 45,900 29,420 HIGH-LEVEL DEVELOPMENTf Jan 650 325 650 325 Feb 650 325 650 325 Mar 650 325 650 325 Apr 580 390 650 325 1,230 715 May 7,570 5,045 650 325 8,220 5,370 June 9,910 6,600 650 325 10,560 6,925 Jul 18,630 12,420 650 325 19,280 12,745 Aug 14,555 9,705 650 325 15,205 lO ,030 Sep 6,405 4,270 650 325 7,055 4,595 Oct 580 390 650 325 1,230 715 Nov 650 325 650 325 Dec 650 325 650 325 ANNUAL 58,230 38,820 7,800 3,900 66,030 42,720 a Agricultural irrigation diversion rate is 3 af/acre; depletion rate is 2 af/acre. bMunicipal water use at 200 gal/d/pers. for diversion; 100 gal/d/pers. depletion. cirrigation development carried on with 10 percent loans amortized over 10-year period. dAssumptions: (no energy development); (6,470 new irrigated acres)c; (31,270 increase in population). eAssumptions: (no energy increase in population). development), (12,940 new irrigated acres)~ (31 ,804 . f Assumptions: (no energy development), (19,410 acres new irrigation of feasible land)c, (34,565 increase in population). -120- TABLE A-4. Monthly and annual water requirements in Bighorn subbasin, year 2000 under three levels of development (af). ENERGY IRRIGATIONa MUNICIPALb TOTAL Divert Deplete Divert Deplete Divert Deplete Divert Deplete Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 70 70 70 70 70 70 70 70 70 70 70 70 ANNUAL 840 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL 490 490 490 490 490 490 490 490 490 490 490 490 5,880 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 28,140 70 70 70 70 70 70 70 70 70 70 70 70 840 490 490 490 490 490 490 490 490 490 490 490 490 5,880 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 2,345 28,140 LOW-LEVEL DEVELOPMENTd 130 1,700 2,220 4,180 3,260 1,435 130 13,055 90 1,130 1,480 2,785 2,175 960 90 8, 710 Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. INTERMEDIATE-LEVEL DEVELOPMENTe 260 3,390 4,430 8,340 6, 520 2,870 260 175 2,260 2,955 5,560 4,345 1,910 175 26,070 17,380 HIGH-LEVEL DEVELOPMENTf 390 5,085 6,650 12,520 9,785 4,300 390 39,120 260 3,390 4,430 8,345 6,525 2,870 260 26,080 Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. 80 80 80 80 80 80 80 80 80 80 80 80 960 Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. ·Neg. Neg. Neg. Neg. Neg. Neg. 40 40 40 40 40 40 40 40 40 40 40 40 480 70 70 70 200 1,770 2,290 4,250 3,330 1,505 200 70 70 13,895 490 490 490 750 3,880 4,920 8,830 7,010 3,360 750 490 490 31,950 2,425 2,425 2,425 2,815 7,510 9,075 14,945 12,210 6,725 2,815 2,425 2,425 68,220 aAgricultural irrigation diversion rate is 3 af/y/acre; depletion rate is 2 af/acre. 70 70 70 160 1,200 1,550 2,855 2,245 1,030 160 70 70 9,550 490 490 490 665 2,750 3,445 6,050 4,835 2,400 665 490 490 23,260 2,385 2,385 2,385 2,645 5,775 6,815 10,730 8,910 5,255 2,645 2,385 2,385 54,700 bMunicipal water use at 200 gal/d/pers. for diversion; 100 gal/d/pers. depletion. cirrigation development carried on with 10 percent loans amortized over 10-year period. dAssumptions: (17.1 mmt strip mine increase); (4,435 new irrigated acres)c; (2,334 increase in population). eAssumptions: (5.9 mmt slurry, 29.3 mmt strip mines increase); (8,690 new irrigated acres)c; (3,145 increase in population). fAssumptions: (1-1,000 mw 14.8 mmt slurty, 36.9 mmt strip mines increase); (13.040 acres new irrigation of feasible land) -121- TABLE A-5. Monthly and annual water requirements in Mid-Yellowstone subbasin, year 2000 under three levels of development (af). ENERGY IRRIGATIONa MUNICIPALb TOTAL Divert Deplete Divert Deplete Divert Deplete Divert Deplete Jan 2,930 Feb 2,930 Mar 2,930 Apr 2,930 May 2,930 Jun 2,930 Jul 2,930 Aug 2,930 Sep 2,930 Oct 2,930 Nov 2,930 Dec 2,930 ANNUAL 35,160 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 75,480 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 139,440 2,930 2,930 2,930 2,930 2,930 2,930 2,930 2,930 2,930 2,930 2,930 2,930 35,160 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 6,290 75,480 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 11,620 139,440 LOW-LEVEL DEVELOPMENTd 250 3,280 4,290 8,075 6,310 2, 775 250 25,230 170 2,190 2,860 5,380 -4,200 1,850 170 '16,820 280 280 280 280 280 280 280 280 280 280 280 280 3,360 INTERMEDIAT~-LEVEL DEVELOPMENTe 505 6,560 8,580 16,150 12,610 5,550 505 335 4,375 5, 720 10,765 8,410 3,700 335 310 310 310 310 310 310 310 310 310 310 310 310 50,460 33,640 3,720 HIGH-LEVEL DEVELOPMENTf 760 9,840 12,870 24,215 18,920 8,325 760 75,690 505 6,560 8,580 16,150 12,610 5,550 505 50,460 645 645 645 645 645 645 645 645 645 645 645 645 7,740 140 140 140 140 140 140 140 140 140 140 140 140 1,680 155 155 155 155 155 155 155 155 155 155 155 155 1,860 320 320 320 320 320 320 320 320 320 320 320 320 3,840 3,210 3,210 3,210 3,460 6,490 7,500 11,285 9,520 5,985 3,460 3,210 3,210 63,750 6,600 6,600 6,600 7,105 13,160 15,180 22,750 19,210 12,150 7,105 6,600 6,600 129,660 12,265 12,265 12,265 13,025 22,105 25,135 36,480 31,185 20,590 13,025 12,265 12,265 222,870 aAgricultural irrigation diversion rate is 3 af/acre; depletion rate is 2 af/acre. 3,070 3,070 3,070 3,240 5,260 5,930 8,450 7,270 4,920 3,240 3,070 3,070 53,660 6,445 6,445 6,445 6,780 10,820 12,165 17,210 14,855 10,145 6,780 6,445 6,445 110.980 11,940 11,940 11,940 12,445 18,500 20,520 28,090 24,550 17,490 12,445 11,940 11,940 193,740 bMunicipal water use at 200 gal/d/pers. for diversion; 100 qal/d/pers. depletion. clrrigation development carried on with 10 percent loans amortized over 10 year period. dAssumptions: (15-1,000 mw, 1-250 mmcfdgas, 59.9 mmt strip mines new de- velopment); (8,410 new irrigated acres)c; (15,887 increase in population). eAssumptions: (3-1,000 mw, 1-250 mmcfd gas, 20.5 mmt slurry, 102.6 mmt strip mines); (16,820 new irrigated acresf; (17,771 increase in population). fAssumptions: (3-1,000 mw, 2-250 mmcfd gas, 1-100,000 b/d syn-crude, 51.6 mmt slurry, 128.9 mmt strip); (25,230 acres new irrig of feasible land)c; (36,250 increase population). -122- TABLE A-6. ~1onthly and annual water requirements in Tongue subbasin, year 2000 under three levels of development (af). ENERGY I RR IGA TI DNa MUNICIPALb TOTAL Divert Deplete Divert Deplete Divert Deplete Divert Deplete Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL Jan Feb Mar Apr t~ay Jun Jul Aug Sep Oct Nov Dec ANNUAL Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL 955 955 955 955 955 955 955 955 955 955 955 955 ll ,460 3,900 3,900 3,900 3,900 3.900 3,900 3,900 3,900 3,900 3,900 3,900 3,900 46,800 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 ll8 ,020 955 955 955 955 955 955 955 955 955 955 955 955 11,460 3,900 3,900 3,900 3,900 3,900 3,900 3,900 3,900 3,900 3,900 3,900 3,900 46,800 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 9,835 118,020 L0\~-LEVEL DEVELOPMENTd 220 2,855 3, 730 7,030 5,490 2,415 220 21,960 145 1,900 2,490 4,685 3,660 1,615 145 14,640 Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. INTERMEDIATE-LEVEL DEVELOPMENTe 440 5,705 7,460 14,045 10,970 4,830 440 290 3,800 4,975 9,360 7,315 3,230 290 43,890 29,260 60 60 60 60 60 60 60 60 60 60 60 60 720 HIGH-LEVEL DEVELOPMENTf 660 8,560 11,195 21,070 16,460 7,245 660 65,650 440 5,710 7,465 14,050 10,975 4,830 440 43,910 130 130 130 130 130 130 130 130 130 130 130 130 1,560 Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. NeiJ. Neg. Neg. Neg. 30 30 30 30 30 30 30 30 30 30 30 30 360 G5 65 65 65 65 65 65 65 65 65 65 65 780 955 955 955 1,175 3,810 4,685 7,985 6,445 3,370 1,175 955 955 33,420 3,960 3,960 3,960 4,400 9,665 ll ,420 18,005 14,930 8, 790 4,400 3,960 3,960 91,410 9,965 9,965 9.965 10,625 18,525 21,160 31,035 26,425 17,210 10,625 9,965 9,965 185,430 aAgricultural irrigation diversion rate is 3 af/acre/; depletion rate is 2 af/acre. 955 955 955 1,100 2,855 3,445 5,640 4,615 2,570 1,100 955 955 26,100 3,960 3,930 3,930 4,220 7,730 8,905 13,290 ll,245 7,160 4,220 3,930 3,930 76,420 9,900 9,900 9,900 10,340 15,610 17,365 23,950 20,875 14,730 10,340 9,900 9,900 162,710 b~1unicipal water use at 200 gal/d/pers. for diversion; 100 gal/d/pers. depletion. cirrigation development carried on with 10 percent loans amortized over 10-year period. dAssumptions: (1-500 mw; 77 mmt strip mines new development); (7.320 new irrigated acreslc; (1.895 increase in population) ; no allowance for Wyoming water depletion, maximum reservoir stora~e 112,000 af minimum; reservoir level 67, DOD a f. If natural flow exceeds all demands (including fish and gHme needs), excess water is stored if space is available-releases made only to supplement consumptive demands. eAssumptions: (2-.l,OOO mw; 26.4 mmt slurry 132 mmt strip); (14,630 new irri- gated acres)c: (2,949 increase in population) maximum reservoir storage 320,000 af, minimum desirable is 50,000 af; instream flow is 60?o of NGPRP recommended flow and stored water is not used to meet this requirement, study period 1944-1973; l~yoming depletion is 40?o of flow at the state line, up to a maximum of 3,000 af; first priority is irriqation and municipal with enerqy production receiving balance •. 1'/atP.r not stored if natural outflow is less than or equal to instream needs. If more,_ stored or used consumptively, stored water may be released for consumptive purposes. fAssumptions (3-1,000 mw, l-250 mmcfld gas, 1,100,000 b/d syncrude, 66.3 mmt slurry, 165.8 mmt strip mine); (21,950 new irrigated acres)c, (6,829 increase in population). l·laximum storage is 320,000 af; no minimum; instream flow calculated for two cases: a) 45 cfs during 1·1arch, April, and May and 15 cfs at all other times, and b) instream flow zero (qugmented if no inflow available) study period 1944-73; l~yominiJ depletion 40?o of the flow at stateline up to maximum of 7,500 af; instream fish and game and irrigation demands receive priority, water for energy use after that; balance of energy water requirement comes by aqueduct from the mainstem of the Yellowstone River. -123- TABLE A-7. Monthly and annual water requirements in Kinsey Area subbasin, year 2000 under three levels of development (af) ENERGY IRRIGATIONa MUNICIPAL TOTAL Divert Deplete Divert Deplete Divert Deplete Divert LOW-LEVEL DEVELOPMENTc Annual 4,740 3,160 4,741 INTERMEDIATE-LEVEL DEVELOPMENTd Jan Feb Mar Apr -95 60 95 May 1,230 . 820 1,230 Jun 1,610 1,075 1,610 Jul 3,035 2,025 3,035 Aug 2,375 1,585 2,375 Sep 1,040 695 1,040 Oct 95 60 95 Nov Dec ANNUAL 9,480 6,320 9,480 HIGH-LEVEL DEVELOPMENTe Jan Feb Mar Apr 140 95 140 May 1,850 1,230 1,850 Jun 2,420 1,610 2,420 Jul 4,555 3,035 4,555 Aug 3,550 2,375 3,550 Sep 1,565 1,040 1,565 Oct 140 95 140 Nov Dec ANNUAL 14,220 9,480 14,220 aAgricultural irrigation diversion rate is 3 af/acre; depletion rate is .2 af/acre. Deplete 3,160 60 820 1,075 2,025 1,585 695 60 6,320 95 1,230 1,610 3,035 2,375 1,040 95 9,480 birrigation development carried on with 10 percent loans amortized over 10 year period. cAssumptions: (no energy development); (1,580 new irrigated b acres) ; (neg. increase in population). dAssumptions: (no energy development); (3 ,160 crease in population). irrigated b (neg. in-new acres) ; ~Assumptions: (no energy development); (4,740 acres new irrigation of feasible land) ; (neg. increase in population). -124- Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec TABLE A-8. Monthly and annual water requirements in Powder subbasin, year 2000 under three levels of development (af) ENERGY Divert 70 70 70 70 70 70 70 70 70 70 70 70 Deplete 70 70 70 70 70 70 70 70 70 70 70 70 IRRIGATIONa Divert Deplete LOW-LEVEL DEVELOPMENTd 750 9,780 12,785 24,070 18,800 8,275 750 500 6,520 8,525 16,045 12,535 5,515 500 MUNICIPALb TOTAL Divert Deplete Divert Deplete Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. Neg. 70 70 70 820 9,850 12,855 24,140 18,870 8,345 820 70 70 70 70 70 570 6,590 8,595 16,115 12,605 5,585 570 70 70 ANNUAL 840 840 75,210 50,140 Neg. Neg. 76,050 50,980 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 ANNUAL 18,840 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 1,800 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 ANNUAL 22,560 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 1,570 INTERMEDIATE-LEVEL DEVELOPMENTe 1,500 19,555 25,570 48,140 37,610 16,545 1,500 1,000 13,04,0 17,050 32,090 25,070 11,030 1,000 100 100 100 100 100 100 100 100 100 100 100 100 18,840 150,420 100,280 1,200 HIGH-LEVEL DEVELOPMENTf 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 1,880 2,255 29,330 38,350 72,190 56,405 24,815 2,255 22,560 225,600 1,500 19,550 25,570 48,130 37,605 16,545 1,500 150,400 190 190 190 190 190 190 190 190 190 190 190 190 2,280 50 1,670 50 1,670 50 1,670 50 3,170 50 21,225 50 27,240 50 49,810 50 39,280 50 18,215 50 3,170 50 1.670 50 1,670 1,620 1,620 1,620 2,620 14,660 18,670 33,710 26,690 12,650 2,620 1,620 1,620 600 170,460 119,720 95 2,070 95 2,070 95 2,070 95 4,325 95 31,400 95 40,420 95 74,260 95 58,475 95 26,885 95 4,325 95 2,070 95 2,070 1,975 1,975 1,975 3,475 21,525 27,545 50' 105 39,580 18,520 3,475 1,975 1,975 1,140 250,440 174,100 aAgricultural irrigation diversion rate is 3 af/acre; depletion rate is 2 af/acre. bMunicipal water use at 200 gal/d/pers. for diversion, 100 gal/d/pers. depletion. clrrigation development carried on with 10 percent loads amortized over 10-year period. dAssumptions: (17.1 mmt strip mines); (25,070 new irrigated acres)c; (3,339 increase in population. eAssumptions: (1-100 mw, 5.9 mmt slurry); (29.3 mmt strip mines); (50,140 new irrigated acres)c; (5,297 increase in population). fAssumptions: (1-1,000 mw, 14.8 mmt slurry); (36.9 mmt strip mines); 75-200 acres new irrigation of feasible land)c; (9,893 increase in population). -125- TABLE A-9. Monthly and annual water requirements in Lower Yellowstone subbasin, year 2000 under three levels of development (af) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ANNUAL ENERGY IRRIGA TIONa MUNICIPALb TOTAL Divert 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 13,020 Deplete Divert Deplete Divert 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 1,085 13,020 LOW-LEVEL DEVELOPMENTd 380 4,900 6,400 12,050 9,420 4,150 380 37,680 250 3,270 4,270 8,040 6,280 2,760 250 25,120 60 60 60 60 60 60 60 60 60 60 60 60 720 INTERMEDIATE-LEVEL DEVELOPMENTe 755 9,795 12,810 24,105 18,830 8,290 755 500 6,525 8,535 16,070 12,550 5,520 500 60 60 60 60 60 60 60 60 60 60 60 60 75,340 50,200 720 HIGH-LEVEL DEVELOPMENTf 1,130 14,690 19,210 36,165 28,255 12,430 1,130 113,010 755 9,795 12,810 24,100 18,830 8,290 755 75,335 80 80 80 80 80 80 80 80 80 80 80 80 960 Deplete Divert Deplete 30 30 30 30 30 30 30 30 30 30 30 30 360 30 30 30 30 30 30 30 30 30 30 30 30 360 40 40 40 40 40 40 40 40 40 40 40 40 480 60 60 60 440 4,960 6,460 12,110 9,480 4,210 440 60 60 38,400 60 60 60 815 9,855 12,870 24,165 18,890 8,350 815 60 60 30 30 30 280 3,300 4,300 8,070 6,310 2,790 280 30 30 25,480 30 30 30 530 6,555 8,565 16,100 12,580 5,550 530 30 30 76,060 50,560 1,165 1,165 1,165 2,295 15,855 20,375 37,330 29,420 13,595 2,295 1,165 1,165 126,990 1,125 1,125 1,125 1,880 10,920 13,935 25,225 19,955 9,415 1,880 1,125 1,125 88,835 aAgricultural irrigation diversion rate is 3 af/acre, depletion rate is 2 af/acre. bMunicipal water use at 200 gal/d/pers. for diversion, 100 gal/d/pers. depletion. cirrigation development carried on with 10 percent loans amortized over 10-year period. dAssumptions: (no energy development); (12,560 new irrigated acres)c; (3,381 increase population). eAssumptions: (no energy development); (25,100 new irrigated acres)c; (3,381 increase in population). fAssumptions: (1-2,300 t/d fertilizer plant); (37,670 acres new irrigation of feasible land)c; (4,125 increase in population). -126- Table B-1 Table B-2 Table B-3 Table B-4 Table B-5 Table B-6 CO-EFFICIENTS AND CONSTANTS FOR SUBBASIN MODEL RUNS TABLES Temperature-indenpendent coefficients . . . . . . Temperature-dependent coefficients: less than 32°F • • • • • • • Temperature-dependent coefficients: 0 greater than 32 F • • • • • Temperature-dependent coefficients: temperature . . . . . . . . . . . . temperature . . . . . . constants Initial values: independent of scenario Initial values: dependent on the scenario -127- PAGE 112 113 114 115 116 116 I ....... N co I Coefficients C(3,2) C(3,3) C(3,6) C(3,ll) C(3,19) C(3, 28) C(4,12) C(4,32) Upper Yellowstone .020893 .000347 .000367 -1.0 .010450 0.0 -• 7 .037402 Clarks Fork .017610 .000294 .000294 -1.0 .008805 0.0 -.427 .009147 TABLE B-1. Temperature-independent coefficients Subbasins Billings Mid-Kinsey Lower Area Bighorn Yellowstone Tongue Area Powder Yellowstone .034310 .26370 .004255 .003570 .035561 .004262 .013678 .000731 .000110 .000090 .000110 .000741 .000089 .000285 .000731 .000110 .000090 .000110 .000741 .000089 .000285 -24.0 -1.0 -.80 -.60 -24.0 -.40 -.80 .017155 .013185 .002128 .001785 .017781 .002131 .000839 -.034310 -.026370 -.002128 -.001785 -.035561 -.004262 -.013678 -6.0 -1.3 -1.0 -1.0 -6.0 -2.0 -1.0 .049167 .033125 .004473 .003660 .079521 .004473 .019016 I ...... N 1.0 I Upper Clarks Coefficients Yellowstone Fork C(l,2) .25EL .25EL C(l ,19) .50EL .5EL C(l ,28) -.2SEL -• 5EL C(l,31) 0.0 0.0 C(l ,32) 0.0 0.0 C(3,31) 0.0 0.0 C(4,9) -.00067 .00055 C(4,10) -.00067 .00055 C(S,l5) .024 .024 C(5,16) .024 .024 C(6,22) 0.0 0.0 C(6,31) -1.0 -1.0 C(7,13) 0.0 0.0 C(7,15) 0.0 0.0 C(8,12) .4-.5EL .4-.5EL C(8,28) 0.0 0.0 C(9,5) S.OEL S.OEL C(9,12) .5EL .SEL C(9,17) S.OEL S.OEL C(9,28) .BEL .BEL C(l0,12) 0.0 o.o C(l0,2B) 0.0 0.0 C(ll,31) 0.0 0.0 C(l2,22) 0.0 0.0 C(l4,21) 0.0 0.0 C(l4,22) 0.0 0.0 C(l4 ,23) o.o 0.0 p = .004 X EXP (.06 X (32 -T)) r = .004 X EXP (.205043 X (32 -T)) EL = evaporation loss TABLE B-2. Temperature-dependent coefficients 0 Temperature less than 32 F Billings Mid-Kinsey Lower Area Bighorn Yellowstone Tongue Area Powder Yellowstone .50EL .25EL .25EL .25EL .5EL ' .25EL .25EL .5EL .50EL .5EL .SEL .5EL .50EL .5EL -.5EL -.25EL -.25EL -• 25EL -• 5EL -.25EL -.25EL 0.0 o.o 0.0 o.o 0.0 o.o 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -.005666 -.0022 -.0002 -.0002 -.005829 -.0002 .0002 -.005666 -.0022 -.0002 -.0002 -.005829 -.0002 .0002 12 .012 .012 .012 p .012 .012 12 .012 .012 .012 p .012 .012 o.o 0.0 0.0 o.o 0.0 0.0 0.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 o.o 0.0 0.0 0.0 0.0 0.0 o.o 0.0 o.o 0.0 0.0 0.0 0.0 0.0 .5-.5EL .5-.5EL .4-.SEL .5-.5EL .5-.5EL .4-.5EL .4-.5EL 0.0 0.0 o.o 0.0 0.0 0.0 0.0 5.0EL 5.0EL 5.0EL 5.0EL 5.0EL 5.0EL 5.0EL .5EL .5EL .5EL .SEL .SEL .5EL • 5EL .SEL 5.0EL 5.0EL .5EL .5EL 5.0EL S.OEL l.OEL l.OEL .BEL .BEL l.OEL .BEL .BEL o.o 0.0 0.0 o.o 0.0 0.0 0.0 0.0 0.0 0.0 o.o 0.0 0.0 0.0 0.0 0.0 o.o 0.0 0.0 0.0 0.0 0.0 0.0 o.o 0.0 0.0 0.0 0.0 o.o 0.0 o.o 0.0 0.0 0.0 0.0 0.0 0.0 o.o 0.0 0.0 o.o o.o 0.0 0.0 0.0 0.0 0.0 o.o o.o I ....... w 0 I TABLE B-3. Temperature-dependent coefficients Temperature greater than 32°F Upper Clarks Billings Mid- Coefficients Yellowstone Fork Area Bighorn Yellowstone Tongue C(l,2) EL l.OEL .SEL .7SEL l.OEL l.OEL C(l,l9) EL l.OEL .SEL .SEL l.OEL l.OEL C(l, 2B) -.2SEL -.2SEL -.SEL -• 2SEL -.2SEL -.2SEL C(l,31) .SEL .SEL .SEL .SEL .SEL .SEL C(l ,32) EVP EVP .SEL EVP 0.0 EVP C(3,31) .0104SO .0104SO .Ol71SS .0191BS .013792 .0017BS C(4,19) -.00097 -.00097 -.OOS666 -.002792 -.001666 -.0002S4 C(4,10) -.00097 -.00097 -.OOS666 -.002792 -.001666 -.0002S4' C(S,lS) 0.0 0.0 0.0 o.o 0.0 0.0 C(S,l6) 0.0 0.0 0.0 o.o 0.0 0.0 C(B,22) 0.0 0.0 0.0 o.o 0.0 0.0 C(6,31) 0.0 o.o 0.0. 0.0 0.0 0.0 C(7,13) .5A .5A .5A .5A .5A .5A C(7,15) A A A A A A C(B,l2) .4-.5EL .4-.5EL .5-.SEL .5-.SEL .4-.SEL .S-.SEL C(B,2B) .3-.BEL .3-.BEL .3-EL ~3-.. BEL .3-.BEL .3-.BEL C(9~5) S.OEL S.OEL S.OEL 5.0EL 5.0EL 5.0EL C(9,12) .SEL .SEL .SEL .SEL .SEL .SEL C(9,17) S.OEL S.OEL .SEL S.OEL S.OEL 5.0EL C(9;2B) .BEL .BEL EL EL .SEL .BEL C(l0,12) .s .s .s ~5 .s .5 C(l9,2B) .7 .7 .7 .7 .7 .7 C(ll,3l) -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 C(l2,22) 1.0 1.0 1.0 1.0 1.0 1.0 C(l6,21) • Sd .5d .Sd .Sd .5d .Sd C(l6,22) . Sd .Sd .5d • 5d .Sd • Sd C(l6,23) d d d d d d EVP is calculated in Sub routine SURFACE and transferred to mainline. EL = evaporation loss A = snowmelt rate d = dampening factor ~~·--~---- Kinsey Lower Area Powder Yellowstone .SEL l.OEL . l.OEL .SEL l.OEL l.OEL .SEL -.2SEL -.2SEL .SEL .SEL .SEL .SEL EVP EVP .00177Bl .00212B .006B39 -.OOSB29 -.000307 -.00033B -.OOSB29 -.000307 -.00033B 0.0 0.0 0.0 0.0 0.0 0.0 0.0 o.o 0.0 0.0 0.0 0.0 .SA .SA .SA A A A .S-.SEL .4-.SEL .4-.SEL .3-EL .3-.BEL .3-.BEL 5.0EL 5.0EL S.OEL .SEL .SEL .SEL .5EL S.OEL 5.0EL EL .BEL .BEL .5 .s .5 .7 .7 .7 -1.0 -1.0 -1.0 1.0 1.0 1.0 .Sd • Sd • Sd .Sd • Sd • 59 d d d I ...... w ...... I Constants SF b K6 K7 c d F G M N p *D = A = T = X13 = X5 = X23 -. .-. ---------::.-------- TABLE B-4. Temperature-dependent coefficients Constants* D SF (X5 + X23) = (d + X5 + X23) A C(T-32)K6 + (Tz32)2 + K7 (XS + Xl5 ) = (bK6) + b 2 EL = CT + dT 2 Xl3 = (l -~ ) XS when 32 < T < M 32 Xl3 = 0 when T > M M - T Xl3 = --;;rp-XS when G ~ T ~ 32; except in Powder Subbasin, where Xl3 = 1 - 5 QRT (J-G ) XS 24 Xl3 = XS when T < G Subbasins Upper Clarks Billings Mid-Kinsey Lower Yellowstone Fork Area Bighorn Yellowstone Tongue Area Powder Yellowstone .01865 .036 .034029 .1470 .02120 . .03145 .0036 .012578 .0758 31.0 31.0 13.0 13.0 10.0 13.0 10.0 10.0 10.0 20.0 20. 50. 50.0 50.0 40.0 30.0 40.0 30. .05 5 .05 5 .12 -5 .07 5 .12 -5 .05 -5 .05 5 .07 5 .05 5 14Xl0=7 14Xl0=7 ll.8Xl0 _7 12Xl0=7 ll.8Xl0 _7 13.4Xl0_7 14Xl0=7 16Xl0=7 14Xl0=7 45Xl0 45Xl0 12.5Xl0 43Xl0 12.5Xl0 47.2Xl0 45Xl0 50Xl0 45Xl0 16.0 16.0 32.0 20.0 32.0 16.0 16.0 14.0 16.0 16.0 16.0 32.0 20.0 32.0 16.0 12.0 14.0 12.0 40.0 40.0 81.0 40.0 81.0 40.0 40.0 40.0 10.5 10.5 49.0 10.5 49.0 10.5 10.5 10.5 3.0 3.0 2.0 3.0 2.0 3.0 3.0 3.0 soil water percolation rate of snowmelt temperature in Fahrenheit snowfall precipitation initial soil water storage I ..... v.J N I Subbasins RE Q Billings Area .40 .85 Bighorn .40 .80 Mid-Yellowstone .40 .85 Tongue .40 .80 Powder .40 .80 Lower Yellowstone .40 .80 Subbasins Billings Area Bighorn Mid-Yellowstone Tongue Powder Lower Yellowstone Table B-5~ Initial values (independent of the scenario) SAVE FC FCMin Ql .24370 .825 .0825 .015 .317350 .94 .094 .02 .396737 1.125 .1125 .015 .015368 .852 .03834 .015 .305471 .830 .083 .015 .358272 1.66 .166 .010 Table B-6. Initial values (dependent' on the scenario) Scenario 53 High 0.0 Inter. 0.0 Low 0.0 High 1.1 Inter. 1.1 High 0.0 Inter. o.o Low 0.0 High .32 Inter. .32 Low .112 Inter. .Z75 Low • Z75 High 0.0 Inter. 0.0 Low 0.0 ---------~ ~-~ ~--~----- Q2 Pl P2 t-1 N .015 .006623 .005956 1944 1973 .02 .056322 .054806 1944 1973 .015 .010ll8 .009549 1944 1973 .015 .000435 .000417 1944 1973 .015 .000457 .000549 1944 1973 .OlD .095730 .087535 1944 1973 STD2 EN 0.0 0.0 0.0 0.0 0.0 0.0 1.1 .002345 1.1 .000490 0.0 • Oll620 0.0 .006290 0.0 .002930 .32 .004385 .32 .003900 .ll2 .000955 • 275 o.o • 275 .000070 o.o .001085 0.0 o.o 0.0 0.0 TABLES PAGE TABLE C-1 Yellowstone River at Billings: regression equations. 118 TABLE C-2 Tongue River near Miles City: regression equations. 119 TABLE C-3 Powder River at Locate: regression equations. 120 TABLE C-4 Big Horn River: regression equation. 121 TABLE C-5 Yellowstone near Miles City: regression equation. 121 TABLE C-6 Yellowstone River near Sidney: regression equations. 122 -133- TABLE C-1. Yellowstone River at Billings: regression equations Month Best Fit Equation 2 Significance r Jan log TDS = 3.16424 -.12912 log Q .073 NS Feb log TDS = 3. 54116 -.20614 log Q .106 NS Mar TDS = 1527.71 -235.17461 log Q .766 ** Apr log TDS = 4.24384 -.34054 log Q .645 ** May TDS = 924.22705 -131.16983 log Q .606 ** June log TDS = 2.57791 -.08230 log Q .063 NS July TDS = 935.46143 -135.05623 log Q .827 ** Aug log TDS = 4.27605 -.35261 log Q .850 ** Sept TDS = 1622.26001 -251.31508 log Q .868 ** Oct log TDS = 5.05812 -.48689 log Q .834 ** Nov TDS = 2255.61938 -368.94141 log Q • .806 ** Dec TDS = 2119.83569 -346.26465 log Q .510 ** ALL MONTHS log TDS = 4.82194 -.44798 log Q .934 ** NOTE: TDS = Average Monthly Total Dissolved Solids, mg/1 Q = Monthly Discharge, acre feet ** = Significant at 1~~ level * = Significant at 5% level NS = Not Significant at 5% level -134- TABLE C-2. Tongue River near Miles City: ~egression equations Month Best Fit Equations 2 Significance r Jan log TDS = 2.968046 -.00001178 Q .373 ** Feb log TDS = 2.8869196 -.0000093196 Q .718 ** Mar TDS = 1445.71 -217.25081 log Q .539 ** Apr TDS = 1524.68 -217.70712 log Q .867 ** May TDS = 1348.75 -191.64864 log Q .546 ** June TDS = 1221.21 -189.03383 log Q .750 ** July TDS = 1513.50 -260.70199 log Q .815 ** Aug TDS = 1686.28 -301.87476 log Q .819 ** Sept log TDS = 3.51775 -.20078 log Q .869 ** Oct TDS = 1647.14 -265.4541 log Q .787 ** Nov TDS = 3.69492 -.21753 .627 ** Dec TDS = 2375.20 -408.74805 .420 ** ALL MONTHS TDS = 1672.10 -267.88599 log Q .583 ** NOTE: TDS = Average Monthly Total Dissolved Solids, mg/1 Q = Monthly Discharge, acre feet ** = Significant at 1~~ level * = Significant at 5~~ level NS = Not Significant at 5% level -135- TABLE C-3. Powder River at Locate: r.egression equ~tions Month Best Fit Equations 2 Significance r Jan TDS = 2009.9 -.04002 Q .154 NS Feb TDS = 3965.75-663.84961 log Q .745 ** Mar log TDS = 3.14148 -.0000027288 Q .857 ** Apr TDS = 1603.99 -.00769 Q .764 ** May TDS = 2952.23 -408.35352 log Q .179 NS ' June log TDS = 3.50657 -.10353 log Q .256 NS July TDS = 4378.26 -707.0542 log Q .580 * Aug TDS = 2171.01 -136.30793 log Q .067 NS Sept log TDS = 3.35371 -.06055 log Q .170 NS Oct TDS = 3479.57 -521.59961 log Q .517 NS Nov log TDS = 3.37988 -.00002 Q .855 ** Dec log TDS = 3.40523 -.00002 Q .749 ** NOTE: TDS = Average Monthly Total Dissolved Solids, mg/1 Q = Monthly Discharge, acre feet ** = Significant at 1~~ level * = Significant at 5~~ level NS = Not Significant at 5% level -136- TABLE C-4. Big Horn River: regression equation Monthly Values for TDSSX are Jan = 551 Feb = 589 March = 609 Apr = 602 May = 610 June = 590 July = 527 Aug = 447 Sept = 475 Oct = 604 Nov = 567 Dec = 571 NOTE: TDS = 57.1 + .93596 TDSSX where TDS = Average Monthly Total Dissolved Solids, mg/1 TDSSX = TDS near St. Xavier TABLE C-5. Yellowstone near Miles City: regression e~uation Log TDS = 5.7522 -.545 log Q where TDS = Average Monthly Total Dissolved Solids in mg/1 Q = Monthly Discharge in acre feet -137- TABLE C-6. Yellowstone River near Sidney: regression equations Month Best Fit Equation 2 Significance r Jan log TDS = 4.45663 -.2983 log Q .655 ** Feb TDS = 2469.44 -339.72412 • 580 ** Mar TDS = 2785.62 -392.1665 .571 * - Apr ' log TOS = 2.83667 -.0000001614 Q .634 ** May TDS = 561.71 -.00017959 Q June TDS = 198.98 + .00003539 Q July TDS = 917.41 -101.69664 log Q .250 Aug TDS = 2303.31 -327.66333 log Q .602 ** Sept log TDS = 2.85842 -.0000002973 Q .543 * Oct TDS = 3745.50 -561.71338 log Q .722 ** Nov TDS = 3852.08 -579.99414 log Q .629 ** Dec TDS = 754.84 -.000344 Q .446 NS NOTE: TDS = Average Monthly Total Dissolved Solids, mg/1 Q = Monthly Discharge, acre feet ** = Significant at 101 10 level * = Significant at 50' 10 level NS = Not Significant at 5~o level -138- Federal Energy Administration. 1974. Project Independence Report. Frederiksen, Kamin, and Associates. 1976. Single Purpose Irrigation Study of the Yellowstone River Basin, Montana. Ireson, A. 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Williams. Bozeman. Northern Great Plains Resources Program. l974a. National and Regional Energy Considerations Work Group Report. Denver. 65 pp. 1974b. National and Regional Water Work Group Report. Denver. Rocky Mountain Association of Geologists. 1972. Mountain Region: United States of America. Geologic atlas of the Rocky Denver. 331 pp. Stanford Research Institute. 1974. Working paper on maximum credible imple- mentation scenarios for the impact of alternative automobile fuel. Menlo Park, CA. Texas Water Development Board. 1972. ,SIMYLD-II. U.S. Army Corps of Engineers. 1972. Streamflow Synthesis and Reservoir Regulation. Washington. U.S. Department of Agriculture. 1951. Soil Survey Manual. Agricultural Handbook II, 18. Soil Conservation Service. Bozeman. 1970a. Montana Soil and Water Conservation Needs Inventory. Soil Conservation Service. Bozeman. 197Gb. Modified Blaney-Criddle method of determining evapo- transpiration values for individual vegetative types. 1972. 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Report on Clarks Fork Division; Wyoming and Montana; Missouri River Basin project. 1963. Report on Yellowstone Division; Montana-North Dakota; Missouri River Basin project. 1971. Feasibility report on HaPdin Unit; Lower Big Horn Division. Pick-Sloan Missouri Basin program. 1972. Appraisal report on re-examination of Missouri-Yellowstone tributaries. Pick-Sloan Missouri Basin program; Montana-Wyoming. Department of Labor. Bureau of Labor Statistics. 1975. Productivity trends, 1980-85. Washington, D.C. Water Resources Council. 1972. OBERS projections series E, Volume 1. Concepts, methods and summary data. 1975. Unpublished price standards; computer printout. Utah State University. 1973. Utah State Water Model. By Hill et al. Western States Water Council. 1974. Western States Water Requirements for Energy Development to 1990. Salt Lake City, Utah. 25-33 pp. Wyoming Legislative Special Subcommittee on Consumptive Water Use. 1974. 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