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HomeMy WebLinkAboutAPA305(}{]£00~& c ~00&®©@ Susitna Joint Venture Document Number 3D5 Please Return To DOCUMENT CONTROL SEDIMENT DISCBABGB DATA FOB SELECTED SITES IN THE SUSITNA BIVBB BASIN, ALASKA, 1981-82 U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 83-870 Prepared in cooperation with the ALASKA POWER AUI'HORITY .. . UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY SEDIMENT DISCHARGE DATA FOR SELECTED SITES IN THE SUSITNA RIVER BASIN, ALASKA, 1981-82 By James M. Knott and Stephen W. Lipscomb U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 83-870 Prepared in cooperation with the ALASKA POWER AUTHORITY Anchorage, Alaska 1983 UNITED STATES DEPARTMENT OF THE INTERIOR JAMES G. WATT, Secretary GEOLOGICAL SURVEY Dallas Peck, Director For additional write to: information District Chief U.S. Geological Survey Water Resources Division 1515 E. 13th Avenue Anchorage, Alaska 99501 Copies of this report can be purchased from: Open-File Services Section Western Distribution Branch Box 25425, Federal Center Denver, Colorado 80225 Telephone: (303) 234-5888 CONTENTS Page Introduction ........................................................... 1 Description of area .................................................... 1 Climate ................................................................ 1 Data collection and analysis ........................................... 2 Sediment discharge ..................................................... 3 Sediment transport ................................................ 3 Suspended-sediment discharge ...................................... 3 Relation between suspended-sediment discharge and water discharge . 4 Bedload discharge and hydraulic characteristics ................... 5 Relation between bedload discharge and water discharge ............ 6 Bed-material data ...................................................... 7 Estimated sediment yield, May to September 1982 ........................ 7 References ............................................................. 8 ILLUSTRATIONS Figure 1. Map showing location, major streams, and U.S. Geological Survey streamgaging and sediment-sampling stations in the Susitna Ri ver basi n ................................................ v 2-5. Graphs showing relation between suspended-sediment discharge and water discharge for: 2. Susitna River near Talkeetna, 1982 water year ................ 9 3. Chulitna River near Talkeetna, 1982 water year ............... 10 4. Talkeetna River near Talkeetna, 1982 water year .............. 11 5. Susitna River at Sunshine, 1982 water year ................... 12 6-9. Graphs showing cross sections and distribution of bedload discharge: 6. Susitna River near Talkeetna, a. June 8, 1982 ......................................... 13 b. July 21, 1982 ........................................ 14 c. July 28, 1982 ........................................ 15 d. August 25, 1982 ...................................... 16 e. September 19, 1982 ................................... 17 7. Chulitna River near Talkeetna, a. June 9, 1982 ......................................... 18 b. July 20, 1982 ........................................ 19 c. July 27, 1982 ........................................ 20 d. August 24, 1982 ...................................... 21 e. September 18, 1982 ................................... 22 8. Talkeetna River near Talkeetna, a. June 9, 1982 ......................................... 23 b. July 20, 1982 ........................................ 24 c. July 28, 1982 ........................................ 25 d. August 24, 1982 ...................................... 26 e. September 20, 1982 ................................... 27 in ILLUSTRATIONS Continued 9. Susitna River at Suns a. June 10, 1982 b. July 19, 1982 c. July 26, 1982 d. August 23, 1982 e. September 17, 10-13. Graphs showing relation discharge, 1982 water 10. Susitna River near Ta 11. Chulitna River near T 12. Talkeetna River near 13. Susitna River at Suns me, \2 ............... 1982 ............ n between bedload year: keetna .......... Ikeetna ......... al keetna ........ ine ............. discharge and water Page 28 29 30 31 32 33 34 35 36 Table 1, TABLES Suspended-sediment data for selected streams in the Susitna River basin, 1981-82 water years 2. Hydraulic and bedload data for selected River basin, 1981-82 water years 3. Bed-material data for selected sampling River basin 4. Water discharge and estimated sediment jrields at selected sites in the Susitna River basin, May to September 1982 .......... 45 stations in the Susitna sites in the Susitna 37 41 43 Multiply foot (ft) square mile (mi 2 ) acre-foot (acre-ft) foot per second (ft/s) cubic foot per second (ft 3 /s) ton, short ton per day (ton/d) degree Fahrenheit (°F) CONVERSION TABLE 0.3048 2.590 1,233 0.3048 0.02832 0.9072 0.9072 >C=5/9 (°F-32) Milligram per liter (mg/L) is a standard reporting unit for which no inch-pound equivalent is used. to obtain meter (m) square kilometer (km) cubic meter (m 3 ) meter per second (m/s) cubic meter per second (m 3 /s) megagram (Mg) or metric ton megagram or metric ton per day (Mg/d) degree Celsius (°C) National Geodetic Vertical Datum of 1929 (NGVD of which relief features and altitude data related; IV 1929): The reference surface to brmerly called mean sea level. SEDIMENT DISCHARGE DATA FOR SELECTED SITES IN THE SUSITNA RIVER BASIN, ALASKA, 1981-82 By James M. Knott and Stephen W. Lipscomb INTRODUCTION The Susitna River is one of the major rivers in Alaska, ranking fifth in drainage area and annual runoff. The upper reaches of the river are under consideration as possible sites for several dams and reservoirs that would be part of a large power- generation system in south-central Alaska. This report presents a summary of sediment and hydraulic data collected at five sites in the Susitna River basin in the area between the proposed damsites and Sunshine (fig. 1). The data were collected during water years 1981-82 to determine total-sediment yield of the Susitna, Chulitna, and Talkeetna Rivers prior to any construction activities. The data-collection effort is part of a cooperative program between the Alaska Power Authority and the U.S. Geological Survey. DESCRIPTION OF AREA The Susitna River basin (fig. 1) lies on the southern flank of the Alaska Range in south-central Alaska. The basin, which has a drainage area of about 19,400 mi 2 , is a contrast of steep rugged mountains towering above wide valley lowlands. Eleva- tions range from 20,320 ft at Mt. McKinley to sea level where the Susitna River empties into Cook Inlet. Tributaries to the Susitna River are commonly referred to as glacial or nonglacial streams. The nonglacial streams are noted for their clarity, even during intense summer rainstorms. Glacial streams are generally turbid throughout most of the open-flow season (May through October). The Susitna River and its larger tribu- taries are all affected to some degree by glacial runoff. Because of the remoteness of the area and rugged landscape, population is sparse and development within the basin has been slow. The economy is based principally on recreation and tourism. The many forests, streams, and mountains are extremely popular with recreationists who enjoy the good hunting, fishing, and scenic beauty of the area. CLIMATE The climate of the Susitna River basin is divided into two broad categories accord- ing to maps prepared by Searby (1968). Higher elevations of the basin are included in the Continental Zone, where diurnal and annual temperature variations are great and precipitation is relatively low. Mean annual temperature ranges from 15 to 25°F (Hartman and Johnson, 1978). The lowlands lie in the Transition Zone where temperatures are less variable than in the Continental Zone. Mean annual tempera- tures generally range from 25 to 35°F. Climatological records for the Talkeetna weather station are probably representa- tive of lowland areas. A summary of Climatological data for this station (Selkregg, 1974) indicates that summer temperatures range from 38 to 62°F, winter temperatures range from -9 to 18°F, and extremes range from -44 to 85°F. Annual precipitation averages 28 in., about 60 percent of which is rainfall. DATA COLLECTION AND ANALYSIS Systematic measurements of sediment discharge and hydraulic data were obtained at four sites in the basin beginning during the 1981 water year (October 1980 - September 1981) and intensifying during the 1982 water year (October 1981 - September 1982). During the 1982 water year, samples were obtained at weekly intervals from the Susitna, Talkeetna, and Chulitna Rivers near Talkeetna and from the Susitna River at Sunshine. The measurements were made to define the amount and distribution of sediment transport by the Susitna River and its major tributaries between Gold Creek and Sunshine (fig. 1). The program included: (1) Measurement of suspended-sediment concentration and discharge, bedload discharge, and channel cross-sectional dimensions at weekly intervals following spring breakup. (2) Analysis of selected samples for particle-size distribution. (3) Supplemental samples of streambed material. Streamflow characteristics were 'defined from data available for existing stream- gaging stations. At sampling sites that did not coincide with streamgaging sites, sufficient discharge measurements were obtainec tions. All measurements were made from a boat; used to ascertain stationing along the measuring to develop stage-discharge rela- either a cableway or sextant were section. Suspended-sediment samples were collected with a standard depth-integrating P-61 sampler (Guy and Norman, 1970). Samples were collected at selected verticals in the stream cross section and analyzed to detennine average values of suspended- sediment concentration and the particle-size distribution of sediment in the water-sediment mixture. Samples of suspended sediment contain particles (usually finer than 2.0 mm) transported in the stream be about 0.5 ft above the streambed. tween the water surface and a point Sediment transported on or within 0.3 feet of bedload sampler (Helley and Smith, 1971, p. 1- sediment (0.062-76.2 mm). Sampling time, numbe and depth, and weight of dry sediment were re bedload discharge. Trap efficiency of the samp teristies of the Helley-Smith sampler and fully evaluated. In the interim, the Geologi method (U.S. Geological Survey, written comm. (Emmett, 1980). A few bed-material samples were obtained at eacn dredge. At some sites, deep and swift waters particles on the streambed made sampling difficu this report, although indicative of the sizes of the streambed was sampled using a 18) designed for collecting coarse of sampling points, stream width corded as a basis for calculating er was assumed to be 1.0. Charac- procedures for its use have not yet been cal Survey follows a provisional 1979) based largely on field tests site using a 6-inch diameter pipe armoring, and the presence of coarse t. Bed-material data presented in particles present in the streambed (less than 128 mm), may not be representative of actual particle-size distribu- tions. Measurements of depth and width at sampling sections were generally obtained during bedload measurements. Depths were measured by sounding with the Helley-Smith sampler at 16 to 25 verticals in the cross section. Stream width was determined from station markings on cableways or from sextant readings. Average velocity was determined by dividing the rated discharge of the stream by the cross-sectional area. SEDIMENT DISCHARGE Sediment Transport Sediment is transported in suspension, by rolling and bouncing along the streambed or as a combination of both. Suspended sediment, as the name implies, consists of particles which are transported in a stream while being held in suspension by the turbulent components of the flowing water. Coarse sediment that is transported on or near the streambed constitutes the bedload. Clay and silt particles usually are moved in suspension and gravel particles move on or near the streambed. Sand particles may be transported either as suspended load, as bedload, or both. Suspended-Sediment Discharge Suspended-sediment sampling for this study was initiated during the 1981 water year. Samples were obtained at monthly intervals at Susitna River at Gold Creek (15292000), Chulitna River near Talkeetna (15292400), Talkeetna River near Talkeet- na (15292700), and Susitna River at Sunshine (15292780). In 1982, the program was modified to include weekly sampling at the Chulitna, Talkeetna, and Sunshine sites and to establish a new site, designated "Susitna River near Talkeetna" (15292100). Sediment-transport rates for the new site are more comparable to those for the other sites than is the site at Gold Creek because of its closer proximity to the other sites. Suspended-sediment data obtained during the 1981-82 water years are listed in table 1. Comparison of data from the five sites indicates both similarities and dif- ferences between the amount of sediment transported by the Susitna River and its tributaries. During the winter period (November - March) suspended-sediment concentrations are generally less than 10 mg/L at all sampling sites. The rivers are generally ice covered and streamflow is at its annual minimum. Precipitation is stored as snow or ice, and glacier melting is at a minimum. Spring breakup usually occurs in May. Concentrations of suspended sediment in- crease rapidly to several hundred milligrams per liter soon after the breakup period. Samples collected in late May and early June typically contain a large percentage of sand, which may indicate that coarse sediment is being primarily eroded from stream channels or banks. Water levels are generally high during this period. Large parts of the river flood plain are covered by ice, so that flow is confined and diverted toward the other bank. Bank erosion by ice-block abrasion may be severe. Suspended-sediment concentrations at the different sampling sites are most variable during the summer (July-August). The larger concentrations typically occur during periods of storm runoff. The Susitna and Talke by glacial runoff; glaciers account for 5 to Concentrations for the sites on these rivers " 15292700) ranged from 90 to 768 mg/L during July etna Rivers are moderately affected 7 percent of the drainage areas. near Talkeetna" (nos. 15292100 and and August 1982. About 28 percent of the drainage area above (15292400) is covered by glaciers. Concentrati site ranged from 766 to 1,270 mg/L during July during periods of maximum glacial melt were periods of storm runoff. During July and Augist trations for the Sunshine site (15292780) ranged sent a mixture of sediment and streamflow contributions and Talkeetna Rivers near Talkeetna. Particle-size data for July and August indicate significant differences in the composition of suspended sediment for the samp! the Chulitna River sampling site ons of suspended sediment at this and August 1982. Concentrations roughly equivalent to those during 1982 suspended-sediment concen- from 424 to 1,430 mg/L and repre- from the Susitna, Chulitna, ing sites. The Susitna River near Talkeetna typically transports the least percentage of sand (21 percent) compared River (29 percent) and the talkeetna River (55 percent). Theto the Chul i tna Susitna River at Sunshine transports an average of 28 percent sand. Relation Between Suspended-Sediment Discharge and Water Discharge A common method for analyzing sediment-transport construct a graph of sediment discharge versus generally expressed as a plot on logarithmic sediment-transport curve. Sediment-transport instantaneous sediment discharge and water disch Talkeetna River, sites are shown in figures 2-5. the silt-clay and sand fractions to examine supplied from glacial runoff and storm runoff, developing the transport curves. Coefficients i from a least-squares fit of log-transformed valui of the variance of sediment discharge to water di The transport curves should be considered representati port during the period of sediment measurement curves are not applicable to winter periods (Octobe during the 1982 water year was about average charges were considerably below extremes for the were much greater than low flows for most years. characteristics at a site is to water discharge. This relation is paper and is referred to as a curves showing the relation between arge for the Susitna, Chulitna, and Similar curves were prepared for possible differences in sediment Only data for 1982 were used in Df determination (r 2 ) were computed ss to provide a qualitative measure ischarge. ve only for sediment trans- (June to September 1982). The r to April). Although runoff in total flow, maximum water dis- period of record and minimum flows Suspended-sediment discharge characteristics were similar at all sampling sites That is, that sediment discharge increased at about the same rates relative to increases in water discharge. Sediment discharge increased exponentially at a faster rate than increases in water discharge. Exponents of water discharge, Q, in the sediment transport relations (figs. 2-5) ranged from 2.11 for Susitna River at Sunshine to 2.37 for Chulitna River near Talkeotna; r 2 ranged from 0.75 to 0.91. Division of suspended sediment into silt-cl.iy and sand fractions, however, indicated some extreme differences between individual sites. At Susitna River near Talkeetna, the amount of suspended sand carried by the stream increased at more than twice the rate of silt-clay with increases in water dis- charge. At the lowest discharge sampled, sand discharge was 1,090 ton/d compared to a silt-clay discharge of 8,840 ton/d. At the highest discharge sampled, sand and silt-clay discharges were both about 35,000 ton/d. At the Chulitna and Talkeetna Rivers, sand and silt-clay discharges both increased at approximately the same rates. Silt-clay discharge increased at a slightly greater rate than sand discharge at the Chulitna River and at a slightly lower rate at the Talkeetna River. At the Sunshine site, sand discharge increased at a much higher rate than silt-clay discharge. For all ranges of discharge sampled, however, the amount of sand trans- ported was less than the silt and clay sized material. Bedload Discharge and Hydraulic Characteristics The bedload and hydraulic data for the three sampling sites near Talkeetna and the Susitna River at Sunshine are summarized in table 2. Bedload data are expressed both as a transport rate in tons per day and in terms of its particle size distri- bution, in percent finer than the indicated sieve size. Samples were collected monthly starting in July 1981 and weekly beginning in June 1982. During the summer of 1981, bedload samples were collected at Susitna River at Gold Creek (table 2). In 1982 the sampling site was relocated downstream to the new station, Susitna River near Talkeetna. The bedload discharge for the Susitna River near Talkeetna ranged from 106 to 2840 ton/d during the 1982 water year. During this same period, the water discharge ranged from 16,900 to 44,400 ft 3 /s. A com- parison of data from the two sites indicates that, for a given discharge, similar amounts of sediment are transported past either site. The grain-size distribution of bedload for both locations showed a fairly even mixture of sand and gravel at the beginning of the summer with a steady decrease in gravel-size material as the summer progressed and flows diminished. This trend was interrupted only during the major storms of the summer, which occurred near the end of July and in mid- September. During these periods of higher flows there is a shift to increasing grain size but the median values still remained in the sand range. In 1982 the bedload discharge at the Chulitna River site ranged from 2560 to 18,300 ton/d, with water discharge varying from 12,500 to 33,400 ft 3 /s. The particle-size distribution on the Chulitna River tended toward a higher percentage of gravel than sand. A typical mixture of 30-40 percent sand and 60-70 percent gravel was fairly constant throughout the summer. Storm-runoff events produced only a slightly larger median particle size. Low flows seemed to produce variable results, some- times increasing and sometimes reducing the median size of bedload. In the 1982 water year, bedload discharge at the Talkeetna River site ranged from 243 to 5790 ton/d for flows ranging from 5960 to 19,100 ft 3 /s. The particle sizes on the Talkeetna River were typically 70-90 percent sand. Exceptions occurred during snowmelt runoff in early June. For this period the size distribution changed to about 65 percent gravel and 35 percent sand. During a September storm the amount of gravel again rose to 73 percent. In June and again in August and September bedload discharges typically ranged from 1000 to 2000 ton/d. For several weeks in July bedload discharge decreased to less than 1000 ton/d. Even during the storm on July 27-28, when stream-flow was 14,300ift 3 /s at the time of the sampling, the bedload discharge was only 885 ton/d. Then! in August it rose to its earlier levels and remained at those levels throughout tfie summer and fall. At Susitna River at Sunshine in 1982, bedload d ton/d; streamflow from 38,500 to 99,000 ft 3 /s. period (June-September), the total bedload discharge at the three upstream sites was two to five times larger than that at Sunshine. This indicates that the excess material, moved through the three sites above Ta scharge ranged from 1050 to 13,600 During most of the 1982 sampling keetna, is either deposited in the Susitna River between Talkeetna and Sunshine or <:n the Chulitna River downstream of the sampling site. The only exceptions to this were on July 26 and again on Sep- tember 18, when the total of the three upstream measured at Sunshine. These two dates corresponc to the two peak flows at Sunshine during 1982. Thus, the data indicate that mater low and medium flows is transported during high "lows. At Sunshine, the sand and water discharge. sand and 80 percent gravel and gravel fractions of In the early part of June This coincided with sites was slightly less than that al deposited above Sunshine during bodload discharge varied with season the mixture was about 20 percent the high runoff flows during that period. Later during August, when the water discharge was low, the gravel propor- tion decreased to a'bout" 15 mixture was affected during increased to 75 percent. percent, with sane the storm events Selected channel cross sections for the four s bedload discharge at individual sampling points, cases the location of the active bedload movement channel where the velocities are greatest. The point across the section were estimated durinc composited from samples obtained at more than on* used, together with the actual weight of the cumul estimate of each point sampled in the cross secti tive approximation for the lateral distribution of Relation Between Bedload Discharge A relation can be defined between bedload dis< similar methods as for suspended sediment, squares method were used to obtain a best-fit Transport curves and corresponding equations de< figures 10-13. The small scatter of data points for the Susitna water discharge has a strong influence on bedloid discharge results in an exponential increase ir Chulitna and Talkeetna Rivers have considerably bedload discharge is influenced by several factors processes are partly responsible for this increased include the available supply of coarse material, action (sand sizes), and timing of sampling vis increasing to 85 percent. This n July and September when gravel tes, with a corresponding plot of are shown on figures 6-9. In most is within the deeper part of the bedload values for each individual . sampling, as most analyses were point. The estimated values were ative sample, to give a weighted on. This method gives a qualita- bedload movement. and Water Discharge harge and water discharge, using Log-transformed data and a least- line through the plotted points, cribing the relations are shown in River near Talkeetna suggests that discharge; an increase in water bedload discharge. Data for the more scatter, indicating that It is likely that glacial scatter. Other factors may bedload-suspended sediment inter- its with respect to storm events. Most visits in 1982 were made during recession periods after peak discharge or during extended base-flow periods. During some periods when either glacial or storm processes were dominant, the slope for the bedload to water discharge relation was similar to that for suspended-sand discharge. Transport curves developed from graphical comparisons between bedload and suspended-sand discharge were used when coefficients of determination (r 2 ) for regression equations were unusually low. BED-MATERIAL DATA Bed-material samples, representative of the sediment occurring in the submerged parts of the river channels, were extremely difficult to obtain because the rivers were too deep and swift for direct access to streambeds. Samples, representative of particles finer than 128 mm, were obtained at Chulitna River near Talkeetna (15292400) and at most sampling points at Susitna River at Sunshine (15292780). A few samples were obtained at the Talkeetna River (15292700) and Susitna River near Talkeetna (15292100) sites. Most samples obtained at the latter sites consisted of a few coarse particles. Bed-material data for 1981-82 are listed in table 3. ESTIMATED SEDIMENT YIELD, MAY TO SEPTEMBER 1982 The sediment yield from a drainage basin is commonly expressed in terms of weight (short or metric tons) or volume (acre-feet or cubic meters). Sediment yields may be estimated by several methods, depending generally on the amount and type of available data. If daily records of streamflow are available, but sediment dis- charge has been measured only infrequently, the method most commonly used involves defining a relation between instantaneous sediment discharge and water discharge and applying this relation to daily values of water discharge. This method was initially used to estimate sediment'yield for this study. At some sites, however, a single sediment-transport curve could not be applied for the entire period because of seasonal changes in the amount and particle-size distribution of sediment for given water discharges. At the Chulitna River site the scatter of bedload-discharge data was such that even the definition of a bedload-water discharge relation is subject to individual interpretation. Several alternative methods were selected to estimate sediment yield for the period May to September 1982. Suspended-sediment yield was estimated using the Col by shift-control method (Col by, 1956). According to Col by, part of the scatter of sediment data in sediment- transport relations is due to random or very short-term fluctuations in concentra- tion, particularly the concentration of the coarse sediments. Part may be due to inflow from tributaries or an actual change that may persist for days, weeks, or seasons. In the opinion of the authors, most of the observed scatter is probably due to seasonal changes and complex mixing of sediment produced from glacial melt and storm runoff, and Col by's method would result in more accurate estimates. Col by suggests that if a change in the relation persists for several days or more the transport curve could be shifted to pass through or near each individual measurement. The method is subjective in that judgment is used to decide whether the measurement is representative of an actual change or a random fluctuation. An important advantage in using this method is that the accuracy of fit of the transport-curve is of small importance. Col byBedload yield also was estimated using the where the scatter in data on bedload discharge curve was constructed based on transport curves transport curves were constructed for silt-cl both suspended-sediment and bedload discharge measurements shift-control method. At sites was extreme, the initial transport of suspended sand. Sediment- sand, and gravel components for Estimated sediment yields for the period May to; September 1982 are given in table 4. Total sediment yields (sum of bedload and suspended-sediment yield) for the sites near Talkeetna ranged from 1.6 million tons for the million tons for the Chulitna River. The Susitna River about 2.8 million tons of sediment from May to September Talkeetna River to 8.4 near Talkeetna transported 1982. Total sediment composition was predominantly silt-clay for the Susitna (71 percent) and Chulitna (61 percent) Rivers near Talkeetna and sand (54 percent) for the Talkeetna River. The amount of gravel ranged from 0.3 percent of total sediment yield for the Susitna River near Talkeetna site to 5.2 and 8.1 percent for the Talkeetna and Chulitna River sites respectively. The total sediment transported past the three sites near Talkeetna (12,800,000 tons) agrees reasonably well with that estimated for the site at Sunshine (13,000,000 tons). Examination of the bedload-size data, however, indicates that less than half of the gravel transported past the upper sites reached Sunshine during 1982. REFERENCES Guy. Technicues Colby, B. R., 1956, Relationship of sediment logical Survey open file report, 170 p. Emmett, W. W., 1980, A field calibration of th of the Helley-Smith bedload sampler: U. Paper 1139, 44 p. H. P., and Norman, V. W., 1970, Field sediment: U.S. Geological Survey tions, Book 3, Chapter C2, 59 p. Hartman, C. W., and Johnson, P. R., 1978, Envi University of Alaska, Institute of Water Re Helley, E. J., and Smith, Winchell, 1971, sure- difference bedload sampler: U.S. P- Searby, H. W., 1968, Climates of the States ESSA, Climatology of the United States, no Selkregg, L. L., editor, 1974, Alaska regional University of Alaska, Arctic Environmental discharge to streamflow: U.S. Geo- sediment-trapping characteristics S. Geological Survey Professional rrethods for measurement of fluvial of Water-Resources Investiga- ranmental atlas of Alaska (2nd ed.): sources, 95 p. Development and calibration of a pres- Geological Survey open-file report, 18 Al aska: Environmental Data Service, 60-49. profiles -- southcentral region: Information and Data Center, 255 p. 100,000 Q oc UJo. CO Zo ? 10,000LU" O oc I o CO Q I- Z LU 5 Q LU CO Q LU | 1000 LU Q. CO CO 100 1000 "III I I I I I QTS = 3.66x10-6 Q2 -23 r2 =0.81 I | 1 1 1 1 1 L I I Q, + c - 4.25 x ID'3 Q 1 -49 0.48 = 7.98 x 10'14 Q3 -84 0.91 Q Stream discharge QTS Total suspended-sediment discharge ~ (plotted points) QS + c Silt-clay fraction of QJS ^sand Sa pc' fraction of 10,000 100,000 WATER DISCHARGE, IN CUBIC FEET PER SECOND Figure 2.-Relation between suspended-sediment discharge and water discharge for Susitna River near Talkeetna,,1982 water year. 1,UUU,UUU >< QC LU 0. CO Zo 100,000 z LU* QC I 8 Q h- 1 5 LU CO Q 10,000 LU Q Z LU 0. C/3 CO 1000 = I I I I I I I I | I I I I I I I I | | I I I | | |J- QT c = 2.79 x 10'6 Q 2 -37 ^ ^\. / r 2 =0.91 \ / y/ , Qs + c = 5.78x10-7 Q 2 -50 iLf' f2 = °'86 1. M/ E 7/ / Jj / Qsand = 8.67 x 10-6 Q 2 -14 // / r 2 = 0.88 / ' Hi4J i="//'/ ~ ^ v * v ^ // Q Stream discharge "" / ' "" 1 QTS Total suspended-sediment discharge - / (plotted points) QS + c Silt-clay fraction of Q-ys ^sand ^"^ ^action of Q-ps ' "~ 1 1 1 1 1 i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1000 10,000 WATER DISCHARGE, IN CUBIC Figure 3.-Relation between suspended-sediment dis River near Talkeetna, 1982 water year. 100,000 = EET PER SECOND charge and water discharge for Chulitna 10 100,0001 < Q en LUo. C/3 O 10,000 z U-fO en <x o W3 Q h- Z LU W3 Q 1000 LU Q Z LU Q. W3 W3 100 TT 3.65 x10'6 Q2 -32 0.79 1000 sand = 7.25x10-7 Q2 -44 r2 = 0.82 Q Stream discharge ^TS Total suspended-sediment discharge (plotted points) QS + c Silt-clay fraction of Q Sand fraction of 10,000 100,000 WATER DISCHARGE, IN CUBIC FEET PER SECOND Figure 4.-RelationL between suspended-sediment discharge and water discharge for Talkeetna River near Talkeetna, 1982 water year. 11 1 ,UUU,UUU > Q QC UJ Q_ CO Z £ 100,000 z lif DISCHARG H- Z UJ 2 Q UJ CO 2 10,000 o UJ Q_ CO CO 1000 _ l i I l l l i l | I 1 1 1 1 II 1 | 1 1 I 1 1 1 1 1. __ 0^ = 9.64 x 1 0"6 Q2 -11 **/ 2 n-rc V s °S + C = 6.79x1 0'5 Q 1 '89r* = 0.75 y f -I s ^ c _ - / * r 2 = 0.53 -0 / J»/, V / l -- I / / / = / "2 1 MM 1 1 1 I 1 1 I 1 1 1 ! 1000 10,000 WATER DISCHARGE, IN CUBIC Figure 5. -Relation between suspended-sediment discharg at Sunshine, 1982 water year. /¥/ =/// i >/ x / . f) , c QQ v i r\*y o^-*Oo/ ^and °-as x iu u // 1^=0.80 / Q Stream discharge ^TS Total suspended-sediment discharge (plotted points) Qj + c Silt-clay fraction of QJS Qsand Sand fraction of Q-ps 1 i 1 1 1 1 1 1 1 1 1 1 1 100,000 :EET PER SECOND e and water discharge for Susitna River 12 100 co < cc 90 80 I | Discharge = 44,400 cubic feet per second bOO Q DC UJ O. COz 0 z uj itX) CDac Io CO Q Q O Q UJ CO 10 I I I _ -T _ - . .1, , T T 0 100 200 300 i i i Measurement <10 ~ r- . __ - - - ~~ A X ^ A 1 .» 400 500 600 DISTANCE FROM LEFT BANK, IN FEET Figure 6a.-Cross section and distribution of bedload discharge, Susitna River near Talkeetna, June 8,1982. 100 95 Q 11 9 ° 3 S 85 ui <C 80 Discharge - 25,000 cubic feet per second 100 200 300 400 DISTANCE FROM LEFT BANK, IN FEET 500 600 UJ CD M CC IEo < -_o Q O O Ul CO 100 £o oc z H z 10 1 _ . _ . . i 1 . 1 1 , 1 1 1 - _ Measurement 410 ~ ^ . _ ,., ..*. m - A. 1. ........ A ,, ..,, ,....( ._ . Figure 6b.-Cross section and distribution of bedload discharge, Susitna River near Talkeetna, July 21, 1982. 100 P 95 90 i i r Discharge = 30,800 cubic feet per second oc 85 80 >- 200 Q CC. LU w 100 zo SCHARGE, Q Q 0 Q LUm 10 1 1 1 1 1 1 _ ; : i T T 1 1 Measurement <10 - 4 «. - _^ ! > I 0 100 500 600200 300 400 DISTANCE FROM LEFT BANK. IN FEET Figure 6c.--Cross section and distribution of bedload discharge, Susitna River near Talkeetna, July 28,1982. LU LU Z Z* 0 LU LU LU IUU 1 95 K- (ARBITRARY DA O 00 00 tO O O CJl O » |< o </J Q 0 Q LU CO DC LU 0. o 2 10 1 1 1 ' 1 1 1 1 Discharge = 1 6,900 cubic feet per second \^ ______________________ / ^X^- ^__ ^ I I 1 I I 1 1 1 1 1 1 1 ~ Measurement <10 _ : : __, 3 100 200 300 400 500 600 DISTANCE FROM LEFT BANK, IN FEET Figure 6d.-Cross section and distribution of bedload discharge, Susitna River near Talkeetna, August 25,1982. 100 z 1 * £=Q D 95 90 "jo: 85 m< 80 100 lif t/) <P UJ CD 10 0 Discharge = 28,900 cubic feet per second 100 I : L I I I I I - Measurement <10 _ 500 600200 300 400 DISTANCE FROM LEFT BANK. IN FEET Figure 6e.-Cross section and distribution of bedload discharge, Susitna River near Talkeetna, September 19,1982. 17,200 cubic feet per second 75 5000 or LU Q. COz o z LUoor x CJ CO Q Q Q LU CO 1000 100 10 0 100 DISTANCE FRO Figure 7a.-Cross section and distribui near Talkeetna, June 9, IS 82 18 Measurement <10 00 300 400 A LEFT BANK, IN FEET on of bedload discharge, Chulitna River <O 00 to BEDLOAD DISCHARGE. IN TONS PER DAY ELEVATION^ IN FEET (ARBITRARY DATUM) 01 o o o o O i o m i s r- m Tl Tlm m H I 1 1 1 1 1 1 1 1 1 1 M II i i i t i i 1 1 1 1 1 1 1 1 l 100 - 95 ID II 90 >;5 85 LUi<. 80 75 5000 QC LU Q. C/J 1 I CJ C/J Q O Q LU 03 Discharge = 33,400 cubic feet pfcr second 1000 100 10 Measurement < 10 T 100 DISTANCE FROM Figure 7c.~Cross section and distribut near Talkeetna, July 27,1982 40000 300 LEFT BANK, IN FEET on of bedload discharge, Chulitna River 20 100 Si 9s LL I-?'Q Z :£ 90 85 LU i cc LU Q. CO i LUa CC< I Q Q LU 03 80 - 75 5000 I I Discharge = 17,900 cubic feet per second 1000 100 10 Measurement < 10 I 100 200 300 DISTANCE FROM LEFT BANK, IN FEET 400 Figure 7d.-Cross section and distribution of bedload discharge, Chulitna River near Talkeetna, August 24, 1982. 21 100 80 - 75 1000 Discharge = 29,600 cubic feet per second Q CC HI 0. CO e UJa QC < Ia CO a 0 < O_ja LU CO 100 Measurement < 10 i 100 2 DO 300 DISTANCE FROli/l LEFT BANK, IN FEET 400 Figure 7e.~Cross^section and distribution of bedload discharge, Chulitna River near Talkeetna, September pL8,1982. 22 ~ 110 II 105 100 95 5000 Discharge = 14,000 cubic feet per second _______I_________I < Q tr UJo. COz o UJO <r <I o CO Q Q Q UJ CD 1000 100 10 Measurement <10 I I 100 200 300 DISTANCE FROM LEFT BANK, IN FEET 400 Figure 8a.-Cross section and_distribution of bedload discharge, Talkeetna River near Talkeetna, June 9,1982. 23 I- LU UJ 25 110 105 100 S 95 1000 Discharge = 8560 cubic feet per second I Q DC LU Q. z o UJo oc 100 I O C/3 Q Q Q UJ CO 10 Measurement <10 100 DISTANCE FROM it - Figure 8b.-Cross section and distribution near Talkeetna, July 20, 1982 200 300 .EFT BANK, IN FEET of bedload discharge, Talkeetna River 24 - - , ~ 110 I ^Si I £<So 105 I- CC <t 100 ^ on UJ 95 1000 Q cc UJa. C/3 I UJ c 100 I cj CO Q 0 Q UJ 00 10 Discharge = 14,300 cubic feet per second I I______ n Measurement <10 100 200 300 DISTANCE FROM LEFT BANK, IN FEET 400 Figure 8c.-Crpss^ection and distribution of bedload discharge, Talkeetna River near Talkeetna, July 28, 1982. 25 to Oi BEDLOAD DISCHARGE, IN TONS PER DAY ELEVATION. IN FEET (ARBITRARY DATUM) o o o o o 1 I I I I I I (O01 o o o U1 o o o m H Ki ^=M m H COO< O -I & O I I I I I I I en (O O)o o (To' I- GC< I- > 5 ^Ecu < 110 105 100 95 Discharge = 14,600 cubic feet per second Q CC LU Q. CO LU O GC < Xo CO 5 Q Q LU CO 5000 1000 100 10 Measurement <10 - 100 200 300 DISTANCE FROM LEFT BANK, IN FEET 400 Figure 8e.-Cross section and distribution of bedload discharge, Talkeetna River near Talkeetna, September 20,1982. 27 to CO 115 Discharge = 64,700 cubic feet per second 1000 100 10 Measurement OO 1 . 100 200 300 700 800 900400 500 600 DISTANCE FROM LEFT BANK, IN FEET Figure 9a.--Cross section and distribution of bedload discharge, Susitna River at Sunshine, June 10,1982. 1000 115 .to Discharge = 61.500 cubic feet per second I 1000 100 10 A 100 Measurement < 10 I A 900200300400 500 600 DISTANCE FROM LEFT BANK. IN FEET 700 800 1000 Figure 9b.-Cross section and distribution of bedload discharge, Susitna River at Sunshine, July 19,1982. 115 Discharge = 99,000 cubic feet per second 2UOO 1000 o OC LU Q. t/j o H ta 0 QC I Q 100 0 o Q LU 00 10 1 - - _ - - _ - - - I r- 1 1 1 1 1 1 1 1 1 1 ,T T,T 1 1 1 Measurement <10 I I - - - - _ - I 100 200 300 700 800 900400 500 600 DISTANCE FROM LEFT BANK, IN FEET Figure 9c.--Cross section and distribution of bedload discharge, Susitna River at Sunshine, July 26,1982. 1000 ELEVATION. IN FEET (ARBITRARY DATUM) BEDLOAD DISCHARGE, 83oqeCDCD ft o D P g. a cr & o o § D w &a > §" 8 Q- "n i 3 O Os» s ELEVATION, IN FEET (ARBITRARY DATUM) 2 w S i. He^- fii $ e c en:r ft s ft cr 00to 10,000 I I Q QC 1X1a- CO I CD V<r < o to Q Q Q HI CD 1000 100 10 = 1.00x10-1 °Q2 -87 r 2 = 0.78 =4.00x10-802-24 = 1.50x10-28 Q 6 -69 r = 0.73 Total bedload discharge (plotted points) / Qgand Sa^ ^action of QB Grave' fraction of Q 1000 10,000 100,000 WATER DISCHARGE (Q), IN CUBIC FEET PER SECOND Figure 10,-Relation between bedload discharge and water discharge, 1982 water year, Susitna River near Talkeetna (15292100). 33 100,000 > Q cc LU c/3z O Z LU O CC I o w Q Q < O_J Q LU CD 10,000 1000 100 Q B = 6.07x 1Q-6 Q2 -14 = 3-47x10-602.14 ^gravel Total bedload discharge (plotted points) !3and fraction of Q.g CJravel fraction of Qg 1000 10,000 100,000 'WATER DISCHARGE (Q), IN CUBIC FEET PER SECOND Figure 11.-Relation between bedload discharge and water discharge, 1982 water year, Chulitna River near Talkeetna (15292400). Transport curves jased on assumed bedload-suspended sand relations. Equations obtained from least-square is analysis were not used (r^ less than 0.10) 34 10,000 _IIII I I I I 0 COz o 03 g uu I o to 0 a < 3 a uu 03 1000 100 10 1 I I I I I I I I 2.89x10'8 Q2 -62 / / Qg Total bedload discharge (plotted points) Q-gpri Sand fraction of Qg Qg rave j Gravel fraction of Qg / 1000 10,000 100,000 WATER DISCHARGE (Q), IN CUBIC FEET PER SECOND Figure 12.-Relation between bedload discharge and water discharge, 1982 water year, Talkeetna River neariTalkeetna (15292700). Transport curve for Qsand basecfon assumed bedload-suspended sand relation. Equation obtained from least-squares analysis was not used (r^ = 0.08). 35 100,000 Q E 110,000 z o oaa UJa <r a a a UJca 1000 100 = 1.25xlO-1 °Q 2 -85 = 5.89x10-10 Q2 -68 / QB Total.bed load discharge / (plotted points) Qsand Sand fraction of Qg Qq rave i Gravel fraction of Qg 1000 10,000 i 100,000 WATER DISCHARGE (Q), IN CUBl£ FEET PER SECOND curve Figure 13.--Relation between bedload discharge and water River at Surishlne"(15292780). Transport bedload-suspended sand relation. Equation was not used!(r2 = 0.07). discharge, 1982 water year, Susitna for Qsand based on assumed obtained from least-squares analysis 36 Table 1 .--Suspended-sediment data for selected stations in the Susitna River basin, 1981-82 water years CO Station name and number Susitna River at Gold Creek (15292000) * Susitna River near Talkeetna (15292100) Water tem- pera- ture(°c) 4.0 .0 .0 .0 10.0 12.5 10.5 12.0 .5 .0 .0 .0 5.0 10.0 10.5 7.5 6.0 7.5 8.0 10.0 11.5 14.5 12.0 13.5 -- 13.0 10.0 10.5 12.0 9.0 6.5 Date of col lection 1980 Oct. 7 1981 Jan. 16 Feb. 12 Mar. 24 May 27 June 23 July 21 Aug. 27 Sept. 28 1982 Jan. 20 Mar. 3 Mar. 30 May 27 July 1 Aug. 19 Sept. 16 1982 June 3 June 9 June 15 June 22 June 30 July 8 July 14 July 21 July 28 Aug. 4 Aug. 10 Aug. 18 Aug. 25 Aug. 31 Sept. 19 Discharge (ft 3 /s) 9,060 2 non,UoU 2,200 1,680 15,900 17,800 42,500 26,600 8,540 2,310 l!o70 1,520 23,600 24,500 13,200 34,600 35.800 46,600 24,200 37,000 30.200 20,700 30,800 24,900 30,800 22,700 20,000 17,700 16,800 19,300 28,700 Sediment concen- tration (mg/L) 1 2 2 164 327 680 158 44 2 1 524 303 238 812 769 548 181 438 438 145 768 383 461 341 289 285 219 251 442 Suspended sedinent Sediment discharge (ton/d) 0 1 OJiO 12 9.1 7,040 15,700 78,000 11,300 1,020 12 2.9 33 33,400 20,000 8,480 75,900 74 , 300. 68,900 11,800 43,800 35,700 8,100 63,900 25,700 38,300 20.900 15,600 13,600 9,930 13,100 34,300 0.002 8 26 -- 7 .- 29 36 -- 8 11 13 22 -- 30 .29 21 30 30 43 32 23 33 0.004 10 37 17 10 __ 40 51 -- , 10 14 16 34 -- 42 35 27 39 43 51 44 29 41 Percent 0.008 14 46 23 21 _- -- -- -- -- -- -- -- 50 -- 32 -- 54 -- -- 47 finer 0.016 19 57 31 27 -- 55 71 -- 16 24 -- 27 52 -- 59 56 44 63 71 77 68 48 53 than size indicated, 0.031 26 64 39 36 -- -- -- -- -- -- -- -- -- 71 58 -- 88 -- -- 60 0.062 37 70 49 49 26 59 84 45 31 46 40 46 73 76 80 72 68 77 87 92 89 72 67 0.125 51 77 58 64 43 76 87 -- 48 59 47 59 79 80 87 78 75 82 90 93 92 80 74 in millimeters 0.250 79 86 80 86 76 88 95 -- 78 32 75 82 90 92 94 86 88 90 96 97 97 94 88 0.500 98 08 97 100 96 99 100 -- 100 100 100 100 100 100 100 97 99 100 100 100 100 100 99 1.000 100 100 100 -- 99 100 -- -- -- -- -- 100 100 -- -- -- -- 100 2.000 -_ -- 100 -- -- -- -- -- -- -- -- -- " -- -- -- -- Table 1.-Continued Water tem- pera- Station name ture and number (°C) Chul i tna River (15292400) .0 __ -- 8.0 -- 14.5 CO 00 __ 6.0 6_5_ 4.5 7.5 7.0 9.0 6.5 9.0 6.0 8.0 6.0 5.0 5.5 6.0 5.0 Date of Discharge collection (ft 3 /s) 1980 Oct. 22 1981 Jan. 14 Feb. 10 Mar. 25 May 18 June 23 July 20 Aug. 24 Sept. 28 1982 U_ f\ Apr. 8 June 4 dumr-9 June 16 June 22 June 29 July 7 July 13 July 20 July 27 Aug. 3 Aug. 11 Aug. 17 Aug. 24 Sept. 1 Sept. 18 4,530 1,620 I C/lfi 1,150 11,700 22,100 34,000 23,500 5,950 789 1,100 11,500 16,900 14,500 19,500 29,000 20,700 22,700 23,100 31,900 23,300 21,300 21,900 18,200 17,300 29,200 Sediment concen- tration 47 3 5 7 500 1,420 1,010 782 129 4 383 424 760 428 880 1,600 1,000 1,270 1,140 1,110 803 766 1,180 830 506 1,680 Suspended sediment Sediment discharge (ton/d) 575 13 21 22 15,800 84,700 92,700 49,600 2,070 8 5 1,140 13,200 34.7UU 16,800 46,300 125,000 55,900 77,800 71,100 95,600 50,500 44,100 69,800 40,800 23,600 132,000 0.002 17 16 11 -- 22 19 24 19 34 26 -- 30 16 24 23 25 24 17 33 0.004 26 34 24 17 -- 32 27 36 25 45 36 -- 44 25 33 34 37 34 26 43 Percent 0.008 35 46 35 24 __ 37 :: 32 56 51 -- 54 30 42 40 48 42 -- 52 finer 0.016 43 56 46 30 -- 46 41 48 39 62 60 65 42 55 51 59 54 42 58 than size indicated^ 0.031 51 64 55 37 54 :: 47 70 69 -- 77 51 67 60 68 65 -- 68 0.062 59 70 62 42 53 59 77 52 58 77 78 71 78 60 73 68 75 75 64 74 0.125 67 75 71 47 -- 68 83 68 64 83 84 76 84 70 77 75 80 81 68 86 in millimeters 0.250 79 84 86 64 -- 88 96 84 75 94 93 83 92 85 87 85 87 93 84 96 0.500 94 94 98 88 -- 99 99 100 98 100 100 99 100 98 99 99 97 100 100 99 1.000 100 99 100 100 -- 100 100 100 -- -- 100 -- 99 100 100 100 -- -- 100 2.000 -- 100 ~- -- -- - ::-- ------ 100 -- -- -- -- -- -- Table 1.-Continued CO Mater tem- pera- Station name ture and number (°C) Talkeetna River near Talkeetna 4.0 (15292700) .0 .0 .0 8.5 10.0 9.0 10.0 1.5 4.0 6.0 -- 7.0 9.5 -- 13.0 10.0 13.0 9.0 11.0 9.0 9.0 8.5 6.0 6.0 Date of Discharge collection (ft 3 /s) 1980 Oct. 1981 Jan. Feb. hit u*Mar. May June July Aug. Sept 1982 Ma v>Plar . Apr. June June June June June June July July July July July Aug. Aug. Aug. Aug. Aug. Sept Sept 8 17 11 f\r £.0 29 24 22 28 . 28 3 9 1 2 9 16 23 29 2 7 13 20 28 3 10 17 24 31 . 17 . 20 3,340 659 530 556 7,300 7,750 15,700 9,900 3,010 O£n toU 432 9,440 17,900 14,200 11,400 12,400 10,700 8,240 6,750 8,880 8,400 14,200 8,980 6,980 6,230 5,920 9,120 17,000 14,800 Sediment concen- tration (mg/L) 20 9 2 4 222 407 498 447 . 61 1 2 333 1,340 302 171 171 309 204 90 226 226 696 206 203 212 179 276 612 301 Suspended sediment Sediment discharge Percent finer than size indicated, in millimeters (ton/d) 0.002 0.004 ion 16 2.9 6.0 4,380 8,520 15 17 21,100 11,900 8 16 496 70 23 8,490 64,800 11,600 5,260 5,730 8,930 4,540 1,640 5,420 5,130 26,700 17 22 4,990 3,830 3,570 2,860 6,800 28,100 7 9 12,000 0.008 0.016 0.031 0.062 44 29 43 56 65 42 27 37 46 55 53 32 45 28 29 29 42 29 36 64 69 27 35 47 56 40 32 41 51 32 16 34 32 0.125 59 74 -- 64 -- 48 -- 40 44 42 59 37 46 72 -- 66 56 43 54 62 46 48 41 0.250 86 85 -- 82 -- 70 -- 66 68 63 82 65 67 92 -- 79 74 62 74 79 82 73 66 0.500 98 98 -- 100 -- 92 100 92 100 100 100 99 100 -- 94 100 100 100 100 100 92 91 1.000 100 100 -- -- -- 99 -- -- 100 ._ -- 100 -- -- 100 -- -- -- -- -- 100 96 2.000 __ -- -- -- -- 100 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 100 Table 1.-Continued Water tem- pera- Station name ture and number (°C) Susitna Riverat Sunshine .0 (15292780) 9.0 11.5 10.5 11.5 1.5 .0 7.5 ^ 7.0 0 7.0 11.0 10.0 9.5 9.5 11.0 10.5 10.5 10.0 9.0 7.0 6.5 Date of Discharge collection 1981 Mar. 25 May 28 June 25 July 23 Aug. 28 Sept. 29 1982 Mar. 2 June 3 June 10 June 17 June 21 June 28 July 2 July 6 July 12 July 19 July 26 Aug. 2 Aug. 9 Aug. 16 Aug. 23 Aug. 30 Sept. 15 Sept. 17 (fWs) 3,800 41,500 55,000 86,300 62,400 19,100 2.660 73,800 64,500 50,800 78,300 75,700 58,700 46,600 59,800 60,800 96,800 62,400 54,000 47,800 38,600 39,800 70,100 86,500 Sediment concen- tration (mq/L) 2 508 735 713 625 76 1 847 414 360 683 702 659 503 800 548 1,430 704 813 726 527 424 1,620 1,300 Suspended sediment Sediment discharge (ton/d) 21 56,900 109,000 166,000 105,000 3,920 7.2 169,000 72,100 49,400 144,000 143,000 104,000 63,300 129,000 90,000 374,000 119,000 119,000 93,700 54,900 45,600 307,000 304,000 0.002 15 13 -- __ 16 __ 17 25 32 25 -- 27 13 -- 28 37 27 19 6 28 0.004 21 36 23 24 -- __ 20 __ 20 33 41 40 -- 39 18 -- 33 42 41 25 9 38 Percent 0.008 29 49 32 36 __ -- __ 27 43 49 45 -- 47 27 -- 43 55 50 34 11 46 finer 0.016 37 60 40 47 -- __ 32 __ 37 53 57 54 -- 60 36 -- 55 67 62 49 22 54 than size indicated, 0.031 45 69 50 54 -- __ -- __ 48 62 66 62 -- 69 47 -- 66 77 73 62 39 65 0.062 58 75 57 60 57 42 52 35 60 73 72 67 75 78 59 61 75 83 81 72 60 72 0.125 71 81 68 70 -- 62 62 42 76 82 78 72 82 85 74 -- 81 88 86 80 79 82 in millimeters 0.250 86 90 87 80 -- 85 95 62 93 92 90 84 90 93 90 -- 89 93 94 90 91 94 0.500 98 99 99 100 -- 97 100 100 100 100 100 100 100 99 99 -- 100 100 100 99 99 99 1.000 100 100 100 -- -- 99 __ -- -- -- -- 100 100 -- -- -- -- 100 100 100 2.000 -_ -- -- 100 -- __ -- -- -- -- -- -- -- -- -- -- -- -- -- Table 2.-Hydraulic and bedload data for selected stations in the Susitna River basin, 1981-82 water years Water discharge Station name and number Date (ft 3 /s) Susitna River at 1981 Gold Creek (15292000) July 22 Aug. 26 Sept. 28 Susitna River near 1982 Talkeetna (15292100) June 3 June 8 June 15 June 22 June 30 July 8 July 14 July 21 July 28 Aug. 4 Aug. 10 Aug. 18 Aug. 25 Aug. 31 Sept. 19 Chulitna River near 1981 Talkeetna (15292400) July 22 Aug. 26 Sept. 29 1982 June 4 June 9 June 16 June 22 June 29 July 7 July 13 July 20 July 27 Aug. 3 Aug. 11 Aug. 17 Aug. 24 Sept. 1 Sept. 18 37,200 25,900 8,540 35,800 44,400 24,200 37,000 30,200 20,800 30,800 25,000 30,800 22,800 20,200 17,800 16.900 19,400 28,900 31,900 22,500 6,000 12,500 17,200 14,600 19,400 28,900 20,600 . 22,800 23,100 33,400 23,500 21,700 22,000 17,900 17,100 29,600 Average depth (ft) 7.76 8.26 5.27 7.37 6.52 5. 15 6.66 5.87 7.28 5.53 5.07 4.96 4.54 4.74 6.06 10.90 10.24 5.95 6.50 8.01 7.33 8.07 9.46 8.23 8.67 8.94 10.07 8.22 8.25 8.50 7.99 7.68 9.16 Width (ft) 625 C60 619 645 623 596 622 603 618 604 596 557 557 585 616 420 295 215 343 347 345 357 389 357 375 368 405 377 361 361 358 354 391 Average velocity Slope (ft/s) (ft/ft) 7.38 8.15 7.42 7.78 7.44 6.78 7.43 7.06 6.84 6.82 6.68 6.45 6.68 7.00 7.75 6.97 7.45 4.69 5.61 6.19 5.77 6.74 7.85 7.01 7.02 7.02 8.19 7.58 7.28 7. 17 6.26 6.29 8.27 -- -- 0.0014 __ .0015 .0018 .0013 .0014 .0015 .0016 .0014 .0013 .0014 .0013 .0013 .0014 -- -- . 00080 .00068 .0012 .0014 .0012 .0011 .0012 .0014 .0014 .0010 .0012 .0010 .00092 .0012 Bedload discharge (ton/d) 1,970 350 1.3 2,840 1,500 831 992 442 324 906 360 600 215 282 106 110 188 372 2,970 3,870 2,900 11,400 18,300 11,400 10,200 13,000 9,610 9,110 13,800 6,900 7,490 9,670 12,100 7,560 7,480 2,560 Particle-size distribution of bed sediment Percentage, .062 .125 .25 2 5 15 3 1 3 2 1 _. 1 1 1 2 1 1 1 1 1 2 2 1 -- 1 1 1 1 2 1 __ 1 1 1 __ 1 1 1 1 , by weight, finer than size (mm) indicated . 5 20 41 78 37 53 24 47 33 65 51 65 70 78 66 69 69 73 63 15 12 15 14 15 11 28 26 16 11 12 15 16 13 12 12 17 22 1.0 28 51 88 47 63 32 58 39 94 71 90 85 98 94 97 97 95 78 22 19 29 28 38 40 53 61 43 20 35 28 38 30 39 25 40 36 2.0 33 55 97 48 69 32 60 40 96 74 92 86 99 96 99 99 97 80 26 27 44 35 47 52 58 65 49 24 40 35 46 35 46 29 56 41 4.0 36 58 100 49 71 33 60 41 97 75 93 88 99 96 100 100 97 80 30 40 55 54 54 63 64 70 58 34 45 42 53 41 54 37 64 45 8.0 38 59 52 75 35 61 43 99 77 94 91 99 96 -- -- 98 82 45 56 77 74 67 74 71 77 71 50 57 53 62 51 66 52 75 53 16.0 44 66 54 79 38 61 46 99 81 96 93 100 97 -- -- 98 84 70 73 91 90 82 83 79 84 84 69 67 63 75 67 80 70 86 64 32.0 61 72 58 86 44 62 84 100 90 100 100 -- 100 -- 100 91 93 89 99 99 95 93 91 91 96 88 85 84 90 90 93 91 95 82 64.0 80 82 74 100 76 64 100 -- 100 -- -- -- -- -- 100 96 97 100 100 100 100 100 100 100 99 100 100 98 100 100 100 100 100 76.0 100 100 100 -- 100 100 __ -- -- -- -- -- -- -- -- 100 100 -- -- -- -- -- -- -- 100 100 -- -- -- -- Table 2.-Continued Water discharge Station name and number Date (ft 3 /s) Talkeetna River near 1981 Talkeetna (15292700) July 21 Aug. 25 Sept. 29 1982 June 2 June 9 June 16 June 23 June 29 July 7 July 13 July 20 July 28 Aug. 3 Aug. 10 fe Aug. 17 M Aug. 24 Aug. 31 Sept. 20 Susitna River at 1981 Sunshine (15292780) July 22 Aug. 26 Sept. 30 1982 June 3 June 10 June 17 June 21 June 28 July 6 July 12 July 19 July 26 Aug. 2 Aug. 9 Aug. 16 Aug. 23 Aug. 30 Sept. 17 16,800 9,900 2,910 19,100 14,000 11,400 12,400 10,900 6,840 9,020 8,560 14,300 9,140 7,070 6.260 5,960 9,200 14,600 89,000 61,900 19,100 71,000 64,700 50,700 78.900 75,400 46.700 59,200 61,500 99,000 63,600 53,800 48,100 38,500 39,200 87,400 Average depth (ft) 8.63 5.19 3.07 7.11 6.03 5.63 5.73 5.70 4.35 4.78 4.83 6.26 4.83 4.35 3.83 3.73 4.53 6.55 12.73 9.99 7.70 10.20 10.10 8.98 12.18 11.10 8.94 9.67 9.70 14.55 10.30 9.40 9.39 8.52 8.81 13.30 Width (ft) 351 335 310 357 350 350 344 349 331 341 344 348 344 338 337 335 351 348 990 975 583 1,020 1,020 967 1,010 1,000 900 939 1,000 1,010 1,000 950 859 685 675 1.000 Average velocity (ft/s) 5.54 5.69 3.05 7.52 6.64 5.79 6.29 5.48 4.75 5.53 5.16 6.56 5.51 4.81 4.85 4.77 5.79 6.40 7.06 6.36 4.25 6.83 6.28 5.84 6.41 6.79 5.80 6.52 6.34 6.73 6.17 6.02 5.96 6.59 6.59 6.57 Slope (ft/ft) -- -- -- .00096 -- -- -- -- -- -- -- -- -- .00049 -- -- -- -- .0015 .0014 .0018 __ .0014 .0015 .0022 .0024 .002Z .0019 .0016 .0017 .0015 .0022 Bed load discharge (ton/d) 2,340 756 25 2,800a 5,790 1,630 1,410 620 1,080 243 516 885 802 2,470 2,380 1,800 1,460 2,740 3,540 3,040 385 6,080 13,600 1,870 2,510 6,390 6,020 3,800 3,960 8,750 3,480 5,220 2,740 1,050 1,480 8,120 Particle-size distribution of bed sediment Percentage, .062 .125 .25 1 12 5 6 1 3 1 __ 1 2 . .- 18 1 3 2 1 1 1 1 1 13 1 22 7 2 2 2 1 12 3 2 3 2 2 4 1 1 5 2 1 1 2 4 1 , by weightj finer than size (mm) indicated .5 46 68 86 35 12 13 32 44 39 66 42 52 38 55 23 14 18 12 42 76 62 15 12 47 18 17 35 52 40 18 60 62 61 55 44 12 1.0 54 85 99 90 30 31 60 73 91 89 64 81 62 97 82 84 84 26 47 79 70 22 17 65 50 22 46 75 54 28 73 81 83 85 63 20 2.0 56 87 100 94 34 35 64 76 93 91 65 85 64 98 93 95 92 27 49 81 70 26 17 65 51 23 47 77 58 30 74 82 84 88 64 23 4.0 57 88 96 36 38 66 77 93 92 65 88 65 99 96 97 93 28 54 83 72 27 18 66 53 25 49 80 62 33 74 83 85 89 64 26 8.0 59 89 97 41 41 71 79 93 93 65 90 67 99 98 98 94 33 60 87 73 30 20 66 57 27 57 85 69 39 75 85 86 90 65 37 16.0 64 91 100 56 46 82 83 94 95 65 92 69 99 99 99 95 49 70 92 77 38 29 69 62 46 71 88 75 53 78 89 92 92 66 60 32.0 78 93 85 59 98 91 96 96 67 95 78 100 100 100 99 82 85 98 83 64 54 75 70 64 86 96 84 77 93 94 98 92 70 78 64.0 97 100 -- 100 86 100 100 100 100 100 100 84 -- 100 100 100 100 100 100 96 100 95 100 100 100 87 97 97 100 100 100 100 100 76.0 100 -- .- 100 -- -- -- 100 -- -- -- -- -- 100 -- 100 -- -- 100 100 100 -- -- ---- a Estimated Table 3.-Bed-material data for selected sites in the Susitna River basin [Sampling point stationing from left bank] CO Station name and number Susitna River at Gold Creek (15292000) Susi tna River near Talkeetna (15292100) Chulitna River near Talkeetna (15292400) Date of collection 1981 Sept. 28 1982 July 28 Aug. 4 Sept. 19 1981 Sept. 29 1982 July 27 Sampl i ng point lOOa i onu I60b 19 Ob llrtL ocnu 280b 310a 370b 120b 200b 29 Ob 410a 550a 130b 210b 310c 400c 540b 140a 210a 300a 430a 570a 90c llOc 130c 150c 170c 190c 210b 180c 240c 29 Oc 330c 380c Bed material Percent finer than size indicated, in millimeters 0.062 0.125 0.25 0.50 1.0 2.0 4.0 8.0 16.0 __ __ -. ._ ._ o __ -. - ._ .- 0 __ o __ - -. 0 1 __ oo __ -- 07 52 81 0 1 1 2 10 57 92 0 2 5 15 30 68 90 ----02 10 18 30 59 83 --04 60 76 79 84 91 0 1 26 47 53 65 78 0 2 24 84 100 -- -- -- ------ 013 15 46 ------ 015 18 44 ----- 0 5 29 34 36 42 52 __ 0 2 5 6 6 8 13 32.0 1 100 7 6 0 4 2 0 94 100 100 98 99 94 71 72 67 5 36 64.0 27 -- 0 53 42 18 0 30 19 5 100 -- -- 100 100 100 89 93 100 24 87 128.0 100 100 -- -- -- 100 -- 100 100 100 100 100 100 100 -- -- -- -- -- -- 100 100 -- 100 100 a Few particles obtained, non-representative sample b Streanibed too coarse for obtaining samples c Representative sample obtained for particles finer than 128 mm Table 3.--Continued [Sampling point stationing from left bank] Bed material Date of Sampling Percent finer than size indicated, in millimeters Station name and number collection point 0.062 0.125 0.25 0.50 Talkeetna River near 1981 Talkeetna (15292700) Sept. 29 60a 90c -- -- -- 0 1 ^flr 150r ISOa 210a 240a 270a 300c 1982 July 28 50b 70b HOc 0 1 7 240a rf_. 300a it^ ?4nh Sept. 20 40b 80c HOc 200c 270r - _____ Susitna River at 1981 Sunshine (15292780) Sept. 30 490a 560a 625a 690a 755a 820c -- 0 2 47 885a 950a 1982 July 26 230c 530c 650c 800c _-_-01 830c 900c -- -- -- 0 1.0 2.0 4.0 8.0 16.0 38888o -- __ __ 0 1 oo 50 74 84 91 95 0 4 o -- 0 b 22 __ __ 0 4 - - 0 1 _____ o Q 64 67 69 74 86 _-02 o 0 3 5 11 23 38 0 1 2 4 6 12 23 32.0 8 2 3 7 2 0 0 0 100 25 7 0 0 65 38 3 0 0 18 41 96 0 0 18 8 4 53 15 64 64.0 0 13 52 100 100 18 11 45 35 100 100 100 61BO " 80 30 0 58 100 100 100 100 36 52 100 54 31 62 100 100 128.0 100 100 100 100 100 100 100 -- 100 100 100 100 100 ion 100 100 100 100 a Few particles obtained, non-representative sample b Streambed too coarse for obtaining samples Table 4.-Water discharge and estimated sediment yields at selected sites in the Susitna River basin, May to September 1982 Station name and number Susitna River near Talkeetna (15292100) Chulitna River near Talkeetna (15292400) Talkeetna River near Talkeetna (15292700) Susitna River at Sunshine (15292780) Drainage area j[mi 2J Period 6,320 May June July August September May - September 2,570 May June July August September May - September 2.006 May June July August September May - September 11,100 May June July August September May - September Water discharge (acre-ft) 920.000a l,700,000a l,500,000a l.OOO.OOOa l.lOO.OOOa 6,200,000a 386,700 1,092,000 1,575,000 1,252,000 1,085,000 5.390,700 203,700 770,200 680,900 447,100 568.600 2.670,000 1,633,000 3,738,000 3,876,000 2,083,000 2,906,000 14,236,000 Suspended sediment (tons) Silt-clay 200,000 450,000 670,000 310,000 330,000 1,960,000 90,000 880,000 1,900,000 1,000,000 1,200,000 5,070,000 30,000 150,000 310,000 56,000 82,000 628,000 400,000 1,500.000 2,800,000 1,800,000 1,900,000 8,400,000 Sand 100.000 350,000 210,000 49,000 140,000 849,000 40,000 400,000 750.000 400,000 490,000 2,080,000 30,000 250,000 200,000 82,000 160,000 722,000 200,000 1,200,000 1,400,000 600,000 820,000 4,220,000 Bedload (tons) Sand 3,000 12,000 11,000 3,900 4.400 34,300 30,000 210,000 140,000 110,000 57,000 547,000 2.000 36,000 29,000 54,000 18.000 139.000 6.000 45,000 78,000 60,000 52,000 241,000 Gravel 900 5,400 1,900 90 1,000 9,290 50,000 220,000 190,000 150,000 70,000 680,000 2,000 45,000 11,000 4,700 21,000 83,700 10,000 130,000 74,000 14,000 43,000 271,000 Silt-clay 200,000 450,000 670,000 310.000 330.000 1.960,000 90,000 880.000 1,900,000 1,000,000 1,200,000 5,070,000 30,000 150,000 310,000 56,000 82,000 628,000 400,000 1,500,000 2,800,000 1,800,000 1,900,000 8,400,000 Total sediment (tons) Sand 100,000 360,000 220,000 53,000 140,000 873,000 70,000 610,000 890,000 510,000 550,000 2,630.000 32.000 290,000 230,000 140,000 180,000 872,000 210,000 1.200,000 1,500,000 660,000 870,000 4,440,000 Gravel 900 5,400 1,900 90 1,000 9,290 50,000 220,000 190,000 150,000 70,000 680,000 2,000 45,000 11,000 4,700 21,000 83,700 10,000 130,000 74,000 14,000 43,000 271,000 Total 301,000 815,000 892,000 363,000 471,000 2,840,000 210,000 1,710,000 2,980,000 1,660,000 1,820,000 8,380,000 64,000 485,000 551,000 201,000 283,000 1,580,000 620,000 2,830,000 4,370,000 2,470,000 2,810,000 13,100,000 a Estimated