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Home My WebLink AboutPelican Cover Inspection Report 1985• PELICAN COVE CREEK DAM -AK 00039 PELICAN, ALASKA co co ALASKA DAM SAFE'l'Y PROGRAM PERIODIC DAM SAFETY INSPECTION REPORT PREPARED FOR: STATE OF ALASKA DEPARTMENT OF NATURAL RESOURCES DIVISION OF LAND AND WATER MANAGEMENT BY CHAS. T. MAIN, INC. FEBRUARY 28, 1985 PELICAN COVE CREEK DArt -AK 00039 PELICAN, ALASKA PREPARED FOR: BY ALASKA OAH SAFETY PRO(';RA.\f PERIOniC DAM SAFETY INSPECTION REPORT STATE OF ALASKA DEPARnfE~lT OF NATURAL RES0URCES DIVISION OF LAND AND \·TATER ~1ANAGEMENT ca~s. T. MAIN, INC. FEBRUARY 28, 1985 ~'\AI~ CHAS. T. MAI~. I~ C. 1893 101 EAST 9TH AVE. SUITE 4A, ANCHORAGE, ALASKA 99501 (907) 272·5433 February 28, 19R5 3945-2-1000 SUBJECT: Alaska Department of Natural Resources Dam Safety Inspection Program Pelican Cove Creek Dam -AK 00039 State of Alaska Department of Natural Resources Division of land and Water Management 555 Cordova Street: Pouch 7-005 Anchorage, Alaska 99510 Attention: Xr. Kyle J. Cherry, P.E. State Dam Safety Engineer Gentlemen: MAIN is pleased to submit herewith our final report on our inspection of Pelican Cove Creek Dam -AK 00039. This inspection was conducted on 30 November 1984. APD/RJT/lem Enclosure Very truly yours, CHAS. T. MAIN, INC. R•:;;~·:/l f.ng/ineers a£~-lu_:___ ~ Alton P. ryavis, Jr. Project '1anager Richard J, Tucker Project Engineer ' ' '--.__ ·; \ \ \ 1 \, . . I , ) Title Sheet REPORT PELICAN COVE CREEK D~~ AK 00039 Alaska, Longitude 136°12.9' and Latitude 57°57.5', Pelican Creek Inspectors: Review team: Owned by Pelican Utility Company Inc. Size Classification: Small Hazard Potential Classification: Significant Alton P. Davis, Jr., P.E. Project Manager -Geotechnical Engineer Richard J, Tucker, P.E. Project Engineer -Hydraulic Engineer ~.~ -,. Approved by: Kyle Cherry, P.E. Dam Safety Engineer Ken Hunt Dam Safety Engineer Carol Larson Hydrologist Approved by: Chas. T. Main, Inc. Alaska Department of Natural Resources a. b. c. d. e. f. g. UNSAFE DA..~ ALASKA DEPARTifENT OF NATURAL RESOURCES STATE DAM INSPECTION PROGRAM Name: Pelican Cove Creek Dam Type: Timber Crib/Timber Buttress I. D. No.: AK 00039 Height: 22 ft. Hazard: Significant Size: Small Location: State: Alaska County: Nearest D/S City, Town or Village: Village of Pelican River or Stream: ~elican Creek h. Owner: Pelican Utility Company i. Condition of Dam Resulting in Unsafe Dam Report: Deterioration of timber cribs and buttresses. j. Description of Danger Involved: Timber cribs could fail at connections allowing rockfill to wash out. Without stabilizing weight of rockfill, remainder of da~ could slide out. Timber buttresses may not be able to withstand hydrostatic and erosive forces which would accompany a 1/2 PMF. Loss of the dam could have significant economic impact on the Village of Pelican which depends on structure for power and water supply. k. Recommedations Given to Governor: Owner should be required to extensively repair or replace the existing structure within the next five years. The new or refurbished dam should be designed and built according to currently accepted engineering practice. 1. Urgency Category: Non-Emergency m. Emergency Actions Taken: None n. Remarks: None ALASKA DAM SAFETY PROGRAM PERIODIC DAM SAFETY INSPECTION REPORT OF PELICAN COVE CREEK DAM -AK 00039 EXECUTIVE SUMMARY On 2 December 1977, President Carter initiated a National Dam Safety Program by directing the Corps of Engineers to administer a program of inspection of all dams classified as high hazard potential by reason of their location. The National Dam Safety Program was completed in 1982. It was intended that each state would thereafter accept respon- sibility for non-federal dams located within their jurisdiction. In July 1966, Governor ~7illiam F.gan signed Alaska Statute AS 46.15 "tJater Use Act" under which the Alaska State Dam Safety Program has been initiated. Under AS 46.15, Pelican Cove Creek Dam was inspected on 30 November 1984 by Chas. T. Main, Inc. under contract to State of Alaska Department of Natural Resources Division of Land and l.J'ater Management. The timber cribbing for Pelican Dam has deteriorated to the point where the long term stability of the structure is in question. The structure should be replaced or extensive remedial work should be undertaken within the next five years. When this remedial work is contemplated, a g~eater spillway capacity, the advisability of a low level outlet and redesign of the intake/flume structure should also be addressed. It is recommended that the State Dam Safety Engineer be given a full set of all construction drawings for any future modifications to the project. It is also suggested that the FERC license be renewed as soon as possible. This inspection report also includes a description as well as details of the new powerhouse and generation units which were constructed to replace the old unit destroyed by fire in January 19e3. i TABLE OF CONTENTS EXECUTIVE SUMMARY TABLE OF CONTENTS GENERAL LOCATION MAP: Figure 1 PROJECT DATA 1. GENERAL 1.1 Authority 1.2 Purpose and Scope 1.3 Inspection Team 2. PROJECT DESCRIPTION 2.1 Location 2.2 Size and Hazard Potential 2.3 Purpose of Dam 2.4 Construction History 2.5 Geology and Soils 2.6 Basin Description 2.7 Description of Project 2.8 Operation and Maintenance 3. 4. FIELD INSPECTION 3.1 General 3.2 Reservoir Area 3.3 Dam 3.4 Abutments 3.5 Outlet Works 3.6 Spillway 3.7 Downstream Channel 3.8 Instrumentation HYDROLOGY 4.1 4.2 4.3 History of Flooding Probable Maximum Flood Frequency Floods 5. HYDRAULIC EVALUATION 5.1 5.2 Spillway Adequacy Flood Routing 6. STRUCTURAL STABILITY ii Classification i ii iv v 1 1 1 2 3 3 3 4 4 5 6 6 .. I 9 9 9 9 10 10 10 11 11 12 12 12 13 14 14 14 15 TABLE OF CONTENTS (Cont'd) 7. PRIOR REPORTS 8. CONCLUSIONS 9. RECOMMENDATIONS APPENDIX A APPENDIX B APPENDIX C APPENDIX D Inspection Photographs Project Plates Stability Analysis Inspection Checklist iii Page 16 17 18 0 30 ------Scale In Miles .......... ~...,(I .,_ .,.,., "'o-. \ ~\ .,,. . "" ) Map Location ~ ...... -------~"-1 \ .,, " \ \ \ '\ \ \ \ \ \ \ ~ .,('1 7; ~ '),. ... .., ~\{ ~\ \ \ \ ) ( PELICAN COVE CREEK DAM LOCATION MAP "'-) I ALASKA DEPT. OF NATURAL RESOURCES OIV. OF LAND AND WATER MANAGEMENT Uf( FEB. 28, 198S 394S 2 CLIIIT Jll ~~AI~ 1~93 iv FIGURE PROJECT DATA PELICAN COVE CREEK DAM -AK 00039 A. GENERAL B. Name . Location Year Built Purpose . Inventory of dam I.D. Number • Hazard Potential Classification Size Classification . Owner DAM Type . Crest Length Crest Width Crest Elevation Height v Pelican Cove Creek Dam Pelican, Alaska 1941 Power/water supply AK 00039 Significant Small Pelican Utility Company Inc. Pelican, Alaska 9Q823 Walt Cothran, Plant ~anager Telephone 907-735-4391 Pelican Seafoods Inc. Seattle, WA (Parent Company) P.O. Rox 85538 Seattle, WA 9Al05 Rooth Ruckley, ~anager Telephone 206-367-8476 Timber crib/Timber buttress 135 ft 12 ft (crib section) 14 7.6 22 ft c. SPILLWAY Type . Location Side Slopes Crest Elevation Bottom Width Length Discharge Capacity D. OUTLET WORKS @ Dam Crest Broad crested weir timber planked in Dam Vertical 142.6 55.5 ft 12 f t 1900 cfs No outlet except for flume used for power and water supply E. RESERVOIR Normal Maximum Water Surface Elevation Water Surface Elevation @ Dam Crest Maximum Storage Volume @ Dam Crest . Maximum Surface Area @ Dam Crest Storage Volume @ Spillway Crest Surface Area @ Spillway Crest F. HYDROLOGIC DATA Drainage Area • Average Annual Discharge Flood of Record Project Design Flood Return Period . Probable Maximum Flood . vi 142.6 14 7.6 60 AF (approx.) 6.5 A (approx.) 27 AF (approx.) 6 A (approx.) 12.95 sq mi 36 cfs (approx.) None recorded, 2000 observed 1900 cfs (zero freeboard) 4.5 years 24,000 cfs 1. GENERAL 1.1 Authority ALASKA DAM SAFETY PROGRAM PERIODIC DAM SAFETY INSPECTION REPORT OF PELICAN COVE CREEK DAM AK 00039 Inspection authority is Alaska Statue AS 46.15 "Water Use Act" signed by Governor ~Hlliam Egan on 1 July 1966. Inspection procedures and criteria for a Phase I Inspection are set forth in the "Recommended Guidelines for Safety Inspection of Dams" Appendix D, Volume I, U.S. Army Corps of Engineers report to the U.S. Congress on National Program of Inspection of Dams, dated May 1975, and published under Title 33CFR Part 222. 1.2 Purpose and Scope The purpose of the Alaska Dam Safety Program, Periodic Dam Safety Inspections is to assemble information and records on existing non-federal dams located within the State of Alaska and to insure continued public confidence in the integrity and safety of these important structures. The scope of this report is to compile results of a visual inspection of Pelican Cove Creek Dam and an examination of currently available information relating to design, construction and performance history of the project. Potential risk to upstream and downstream residents is evaluated and pre- liminary spillway adequacy and structural assessments are made. Finally, adequacy of existing records and documents relating to the project are discussed and recommendations for additional studies and/or remedial actions are made. -1- 1.3 Inspection Team The inspection of Pelican Cove Creek Dam was conducted on 30 Novemher 1984. The inspection team was composed of the following personnel: CHAS. T. MAI~, INC. Alton P. Davis, Jr. Richard J. Tucker Project Manager/Geotechnical Project Engineer/Hydraulics Mr. Tom Whitmarsh of Pelican Utility CoMpany Inc. accompanied the inspection team. Mr. Walt Cothran, Plant Manager for Pelican Seafoods Inc., assisted the inspection team in locating available documents for review and supplied valuable information regarding the construction history of the project. The courtesies extended to the inspection team by Pelican Seafoods Inc. is gratefully acknowledged. -2- 2. PROJECT DESCRIPTION 2.1 Location Pelican Cove Creek Dam is located on Pelican Creek at 57° 57.5' North Latitude, 136° 12.9' West Longitude on Chichagof Island within the Tongass National Forest. The dam site is approximately equidistant from Sitka and Juneau as shown on Figure 1. The Village of Pelican is located on Lisianski Inlet approximately one quarter mile downstream of the dam site. The dam is owned and operated by the Pelican Utility Company of Pelican, Alaska, which is a subsidiary of Pelican Seafood Inc. The National Dam Inventory for the State of Alaska identifies this dam as AK 00039. 2.2 Size and Hazard Potential Classification 2.2.1 Size Classification: The height of Pelican Cove Creek Dam is 22 feet and the reservoir has a maximum estimated storage capacity of 60 acre-feet at the dam crest. The size classification is determined by the height of the dam or the maximum storage capacity whichever gives the larger size category. A small size dam is less than 40 feet in height and less than 1000 acre-feet of maximum storage capacity. Pelican Cove Creek Dam is therefore classified as Small Size based on both height of dam and maximum storage capacity. 2.2.2 Hazard Potential Classification: Pelican Cove Creek Dam is classified as Significant Hazard Potential for damage and loss of life in the event of failure. Significant Hazard Potential is not a quantitative assessment of the safety of the dam, it simply states the hazard if the dam should fail for any reason. The downstream area is heavily forested and has a narrow channel exiting into Lisianski Inlet. There are no dwellings in the floodplain until the creek reaches tidewater, adjacent to the outlet of the creek into Lisianski Inlet. MAIN feels that failure of the dam on Pelican Creek would be of no consequence in this area due to the small storage in the reservoir relative to the available area of the floodplain. -3- Although MAIN feels that potential for damage and loss of life due to failure of the dam would be low, loss of the dam would effect considerable economic loss to the town and to the local fish processing industry. The project impounds the local water supply as well as provides low cost power which makes the continued presence of the cold storage company attractive. Because of the great disruption to the local economy which would follow failure of the dam, Pelican Cove Creek Dam is classied as Significant Hazard Potential. 2.3 Purpose of Dam Pelican Cove Creek Dam was constructed in 1941 to provide water supply and hydroelectric power for the Pelican Seafoods fish processing facility. The project presently continues to be used for water supply and hydro- electric power for the Village of Pelican, including the fish processing plant. 2.4 Construction History The dam was constructed in 1941 by Mr. Gus Savella whose last known address was Port Angeles, Washington. ~r. Charlie Raatikainen was the local person supervising the construction. Design of the project was by Frank Allelcalf of Juneau, Alaska. A FPC license ~w. 1521 was issued July 31, 1942 and has recently expired. The owner is presently engaged in preparing a new application for a FERC license. In January 1983 the original powerhouse was destroyed by fire and was replaced in June 1984 with a new powerhouse constructed on the old foundation. The new powerhouse contains two generating units. One unit is rated at 650 kW, while the other at 100 kW. A full set of drawings is available at the Alaska Corps of Engineers Office. -4- 2.5 Geology and Soils 2.5.1 Regional Geology: Chichagof Island lies in a broad belt that strikes northwest and southeast in confornance with the prevailing trend in southeastern Alaska. Within this belt, intrusives, made up largely of quartz diorities and other granitoid rocks, have been intruded parallel to the stratified country rock. These intrusions were accompanied by metamorphism of some rocks and extensive deformation of pre-existing rocks including folding, breaking and moving of rocks by uplifting along vertical faults, strike-slip faults and possible thrust faulting. 2.5.2 Site Geology: The damsite is on Pelican Cove Creek, a deep, steep, narrow gorge running down the mountainside from a narrow plateau to tidewater. Bedrock has been identified as a syenite. At the damsite, the weathered zones have eroded away due to water action and the exposed foundation rock is a moderately jointed, sound, durable material. A general site map showing the area topography is included in this report (Plate 1). 2.5.3 Seismicity: Chichagof Island lies within the broad region of ~arthquake activity that includes much of southeastern Alaska, south- eastern Yukon and northwestern coastal British Columbia. Records are few and of short duration due to the meager population and scarcity of seismology stations in the region. The Village of Pelican is located on the hidden Peril Strait fault which appears to join the Fairweather fault with the Chatham Strait fault (Lynn A. Yehle, 1974). The records show that, within a radius of SO miles, an earthquake of magnitude 7.1 on the Richter scale took place in 1927 and one of magnitude 6.7 took place in 1973. The village is in seismic zone 4, ER 1110-2-1806 dated 16 May 1983. An earthquake epicenter map is included in Appendix R, Plate 2. -s- 2.6 Basin Description The drainage basin (see Plate 1) above Pelican Dam is 12.95 square miles and is located about 1/4 mile above the mouth of Pelican Creek which empties into the Lisianski Strait near Pelican about 70 miles west of Juneau. The drainage basin is one of a multitude of watersheds which drain excess precipitation and snowmelt from Chichagof Island. Basin topography ranges from a steep, narrow canyon at the damsite to gentle, sloping streambeds in the intermediate elevation zone with headwater areas beginning on steep precipitous mountain slopes whose peaks reach about 3000 feet. Lower elevations of the watershed are covered with dense stands of conifer trees underlayed by a thick blanket of low grow- ing vegetation and a surface mantle of spongy peat. As elevation increases, vegetation decreases. At about 1500 feet, vegetation is near non-existent with the soil mantle removed to near bedrock by past glaciation. Pre- vailing maritime storms drench the area with heavy precipitation during the summer and cover the higher elevation zones with deep snow in the winter. As temperature moderates in the spring, snowmelt occurs, leaving the island nearly snowfree by the end of July. Late October and early November rain normally produces the most severe runoff con- ditions when 24 hour accumulations may reach 8 inches or more. Climatic data are not available at Pelican; however, climatic conditions at Sitka would be representative of those at Pelican. Climatic records for Sitka for a 99 year period show a mean annual temperature of 43°F with extremes of 90°F and -l5°F. Average annual precipitation is approximately 97 inches. 2.7 Description of Project Pelican Cove Creek Dam is a rock filled timber crib and timber buttress structure approximately 135 feet long and 22 feet high at its high point (Photo No. 1). The cribs are all skinned logs of Alaska yellow cedar approximately 8.5 feet on centers. The logs have been notched and pinned at the connection points (Photo No. 2). The spillway is a timber overflow structure 55.5 ft wide. The upstream timber facing -6- which is 3 x 8 Alaska yellow cedar planking extends 1 foot above the chute (Photo No. 2). The top of the dam adjacent to both abutments has been raised about 6 feet with a nearly vertical yellow cedar plank face supported by timber buttresses. A 4 x 5 foot timber flume leads from an intake to the right of the spillway. The intake is controlled by a steel slide gate that is raised and lowered by a chain. The flume carries water along a steep side hill 636 feet to an overflow structure. Partway along the flume is a 90 foot section of rock tunnel. The flume is constructed of untreated timber lined with plywood. The overflow structure is the intake water supply line to the Village of Pelican and for the 36 inch diameter wood stave penstock which conveys water to the new powerhouse and turbine. The two generating units are rated at 100 kW and 650 kW. Due to hydraulic limitations, the turbines are currently capable of 75 and 520 kW, respectively. A preliminary design for a new higher dam has been prepared. This new dam would be constructed in a narrow portion of the channel immediately downstream of the existing structure. Unless Pelican Seafoods or the Town of Pelican can get a grant from the State or the Alaska Power Authority is willing to construct the project, repair of the existing structure appears to be the most likely alternative. 2.8 Operation and Maintenance Pelican Cove Creek Dam impoundment supplies water for water supply and hydroelectric power for the Village of Pelican and the Pelican Seafoods processing plant. Release of water is through an intake to a timber flume and rock tunnel to a forebay where a wood stave pipeline carries water to the powerhouse and another pipe conveys potable water to the village. The small volume of normal storage (approximately 27 acre-feet) provides little storage to maintain hydroelectric generation during periods of low flow. The development would generally be considered to be a run-of-river operation. -7- There are no formal records of project maintenance: however. Pelican Utility Company has one full time employee responsible for inspecting and maintaining the system. The project appeared to be well maintained and is checked at least once a day. -8- 3. FIELD INSPECTION 3.1 General The field inspection of Pelican Cove Creek Dam was conducted on 30 November 1984 by Messrs. A. P. Davis, Jr. and R. J. Tucker of Chas. T. Main, Inc. Personnel from Pelican Utility Company also accompanied the inspection team as stated in Section 1.3. The Inspection Checklist is included as Appendix D. 3.2 Reservoir Area At the time of the inspection, the reservoir was at approximate elevation 138.0 or 5 feet below the spillway crest. The upstream basin is shown on Photo No. 4. The reservoir is relatively small (27 A-F) and appeared to contain many windfalls, rotting stumps and other forest debris. Those portions of the shoreline visable from the dam appeared stable with no evidence of slides. 3.3 Dam 3.3.1 Crest: Pelican Cove Creek Dam is a timber crib and timber buttress structure which spans a natural fall above a steep gorge on Pelican Creek (Photo No. 1). The crest appeared level with no signs of settlement or displacement. The rock fill below the timber deck appears to have settled or perhaps was never filled to the top of the structure. The timber buttress which supports the nonoverflow sections on each side of the spillway appeared to have deteriorated with some rot, checking and broken planks evident. 3.3.2 Upstream Face: Examination of the timber planked upstream face was difficult due to snow cover (Photo No. 3). Those sections which were visable showed signs of deterioration due to rot and a few planks were broken with portions missing. There were signs of some minor settlement at the waterline. -9- 3.3.3 Downstream Face: The downstream face of the overflow section showed significant deterioration of the log cribs (Photo No. 2), especially at the connections. The rock fill was filled to about 3 feet below the top of the planking. It is not known whether this has been due to settlement, washing out of some of the smaller pieces or whether the structure was not filled to the top originally. 3.4 Abutments Both abutments appeared to be sound rock. The structure appeared to be well sited with respect to the abutments. With the reservoir drawn down approximately 5 feet, there were no signs of sigificant leakage at the abutment contacts. Previous reports have reported significant abutment abrasion due to the effect of jetting action due to leaks at higher reservoir levels. 3.5 Outlet Works The only outlet for the project is the intake for the timber flume which leads to the intake for the wood stave penstock and water supply pipeline. This sytems would have the capability of lowering the reservoir approxi- mately 6 feet during low flow conditions. The intake gate is deteriorated and is in a precarious location for operating personnel, especially during high water. The gate has been noted to seal poorly which hinders maintenance work on the flume and forebay. 3.6 Spillway The spillway includes the majority of the timber crib portion of the structure (Photos No. 1 and 3). The upstream planking and top decking show some deterioration but are in usable condition. The spillway discharge impinges on the bedrock downstream of the dam. There are no signs of erosion of the bedrock or deterioration of the structure due to high spillway discharges. -10- 3.7 Downstream Channel The downstream channel was inspected to evaluate potential hazard to life and property in the hypothetical event of dam failure. Below the damsite the stream passes through a very steep, narrow channel before exiting into a tidal estuary some distance upstream of the Pelican hydropower plant and above where a timber walkway crosses the stream (Photo No. 6). Due to the relatively small reservoir storage, the constricted nature of the downstream channel and the broad channel in the estuary, it is not felt that a breach of the dam would be likely to cause significant down- stream damage. Photo No. 7 is an air photo showing the dam and downstream river channel. 3.8 Instrumentation Core samples of the log cribs were reported to have been taken by the U.S.F.S. These were said to show the timbers in generally good condition. There are no other records of instrumentation or monitoring programs at the dam. -11- 4. HYDROLOGY 4.1 History of Flooding No specific details of past flooding on Pelican creek are available. Personnel at the site indicated that it is not uncommon during high flows for the reservoir level to be 5 feet over the spillway crest. 4.2 Probable Maximum Flood The September 1978 Phase I National Dam Safety Inspection Report which was prepared by the Alaska District u.s. Corps of Engineers included details of a synthetically derived PMF. The PMF for Pelican Reservoir was derived using computer program HEC-1 and assuming ''Snyders" unit hydrograph coefficients for CP and TP. Probable Maxium Precipitation used to determine PMF was provided by the National Weather Service (NWS) for the Swan Lake hydropower study, a small basin with similar hydrologic characteristics and geographic location. Based on the drainage basin characteristics, the Corps selected precipita- tion and runoff characteristic parameters which produced a PMF with a peak inflow of 16,000 cfs. For this report, MAIN reviewed this previous analysis and has concluded that the time to peak of the unit hydrograph (TP) of 3.0 hours is inappropriate and that a much shorter time should be selected. MAIN redetermined the PMF by applying the Soil Conservation Service's "Triangular Unit Hydrograph" technique. The estimated time of concentration correction factor is 1.8. The duration of the unit hydrograph is 0.125 hour and Tp = 1.128 hours, Qp = 5556 cfs, and Tb = 5.66 hours. The PMP used to determine PMF was obtained from the Hydrometeorological Report No. 54, (HMR 54). The 24 hour PMF for a 10 square mile area is about 19 inches. By using Depth Area Duration (DAD) relationships illustrated in Figure 30 of HMR U54 Report, the PMP values for 6, 9, 12, 18 and 24 hour durations were estimated to be 9.31, 11.1, 11.78, 13.87, 16.91 and 18.62 inches. -12- Assuming a loss rate of 0.1 inch per hour, the peak flow of the PMF was computed to be about 24,000 cfs for the 12.95 square mile drainage area. MAIN has adopted this new discharge for this report. 4.3 Frequency Floods Because the Pelican Cove Creek drainage area 12.95 square miles at the dam site is not gauged, the determination of the frequency flood peaks was done by a statistical analysis of the gauged streams which have similar hydrometeorologic characteristics and by adapting their results to the Pelican Cove Creek dam site. The streams selected for the analysis are Tonalite Creek near Tenake, (Station No. 15106980, drainage area 14.5 square miles), and Kadashan River near Tenake {Station No. 15106920, drainage area 10.2 square miles). They are located 15 miles south-southeast from the site. The data for both streams were analyzed by using a Log Pearson Type III dis- tribution. The adaption of the results to Pelican Cove Creek dam site was made by the assumption that the annual peak discharges of the meteorologically similar watersheds are proportional to the square roots of the drainage areas. The results are tabulated below: Return Period (Years) 2 10 25 50 100 200 Qpeak (Pelican Cove Creek Dam Site) (cfs) -13- 1660 2530 2870 3080 3270 3450 5. HYDRAULIC EVALUATION 5.1 Spillway Adequacy The project spillway is an uncontrolled overflow structure with a total length of approximately 55 feet. Although the upstream planking forms a sharp crest about 1 foot above the timber deck, it is expected that the spillway acts as a broad crested weir during flood discharges. Using the appropriate discharge coefficients, the capacity of the spillway at elevation 147.6 (zero freeboard) equals about 1900 cfs. This report has classified this project's hazard potential as Significant. Projects classified as Significant Hazard Potential should be capable of passing a flood equal to 1/2 PMF or 12,000 cfs. A flood with a magnitude of 12,000 cfs would overtop the timber buttress structure by approximately 7 feet. It is questionable whether the timber buttress could withstand the hydrostatic pressure and erosive forces which would accompany such a flood. 5.2 Flood Routing Due to the relatively small, steep sided reservoir and uncontrolled spillway at Pelican Cove Creek Dam, it is expected that Pelican Lake would have little attenuation effect on major floods. -14- 6. STRUCTURAL STABILITY In reviewing available drawings and reports regarding the Pelican Cove Creek Dam, no stability calculations or stability assumptions were found. MAIN elected to analyze the timber crib spillway using our computer program STAGR. For MAIN's analysis, a one foot section of the spillway section was selected. The details of this study are presented in Appendeix c. Stability analyses were conducted for normal, earth- quake and ice conditions with the headwater at normal operating levels. In addition, the structure was analyzed for the zero freeboard and PMF loading conditions. The results shown in Appendix C indicate that the structure is stable for all anticipated loading conditions. Examination of the timber cribs and timber buttress raised considerable doubt concerning their long term structural stability, especially during major floods. Although the timber crib structure was shown to be stable if the connections remained intact, failure of one or more of these connections could result in progressive failure of the entire dam. In order to insure its continued integrity, extensive repairs should begin as soon as possible. These could include installa- tion of a new crib immediately downstream thereby buttressing the old dam, an entirely new. concrete dam downstream adjacent to the rock tunnel or a complete demolition and rebuilding of the existing structure in its present location. -15- 7. PRIOR REPORTS A Phase I National Dam Safety Inspection of Pelican Cove Creek Dam was conducted by the u.s. Corps of Engineers and a report prepared dated September 1978. This report is on file with the State Dam Safety Office and was reviewed prior to MAIN's inspection. USKH Engineering has prepared a series of two reports entitled "Pelican Power Alternatives Phase I -Reconnaissance Assessment" and "Pelican Power Alternatives Phase II -Feasibility Study." These reports have been reviewed and key information has been extracted as prudent. No other documents were found relating to the design of Pelican Cove Creek Dam. -16- 8. CONCLUSIONS From this inspection and analysis of Pelican Cove Creek Dam, MAIN presents the following conclusions: 1. A Hazard Potential Classification of Significant is appropriate due to the economic loss that would result due to loss of hydroelectric generation and water supply for the Village of Pelican and Pelican Seafoods. 2. The dam and its appurtenances show significant deterioration and are in need of extensive repairs or replacement. 3. Analysis of spillway adequacy indicated that the structure can only pass 1900 cfs before the dam is overtopped. This flood has a recurrence interval of less than once in five years. 4. If a 1/2 PMF were to occur, the stability of the buttress sections could be in question due to hydrostatic loading and erosive forces. The timber crib structure is stable provided the connections remain intact. -17- 9. RECOMMENDATIONS 1. Pelican Cove Creek Dam should be repaired, replaced or a new dam built downstream within the next 5 years. 2. The design of the new or rebuilt structure should include a low level release, a larger spillway capacity which will prevent overtopping the dam at the abutment~ and an improved intake scheme which will make operation less hazardous. 3. A new FERC license should be obtained. -18- APPENDIX A INSPECTION PHOTOGRAPHS 30 NOVEMBER 19R4 • ' ~\ No. 1 Timber crib spill- way looking toward left abutment. No. 2 Typical log crib connection. No. 3 Spillway crest and intake looking toward right abutment . • I J No. 4 Reservoir upstream of dam. No. 5 New powerhouse from timber walkway crossin ~ lower Pelican r.reek. No. 6 Downstream river channel • 7. Air Photo of Pelican Cove Creek Dam 27 July 1977 (Flight 976. Frame No. 3) APPENDIX B PROJECT PLATES 0 2 -----S c a le In Mllea t -N ~ PELICAN COVE CREEK DAM GENERAL SITE MAP Al-ASKA DEPT. fW NATURAL RESOURC[S DI Y. fW LAND AND WATER MANAGEMENT ~AI~ 1893 1111 r~•. l i ,IMS llU•t U t l llfl 1145 t C'l 0 "• • ., w ~ \ 0 C'l .... • .. 4 ... H G T H E H T s I u • 0 T XI E y XII 1841-1959 t-!i lne 1 '164 I'' -~------------·--------------·-..... .IU ..... .... .... .,.0 •. an •··· .... ... e··· e.H ..... •" .... ·-· .. ,. •''' ..... '!1 .......• tJ .'!I e:~ ........ . •... ::~· ·-..... ..... ;:: 1' -··-• ... ·- B 0 . .. , -... ,.. ·- ·. ·· ... . R T L VE MAP OF EARTHQUAKES ACCUMULATI ....... WAGNITUD[ a 4 •ut• to ''''U•H•' '•"o• TO "'u"' u .. O[IIIJ!.,t .. ( g .. UWI( Ill\ t -N ] s .. H A ··- I ' I ' I I ·- .... PLATE 2 APPENDIX C STABILITY ANALYSIS CASE I CASE II CASE III CASE IV CASE V CASES USED IN STABILITY ANALYSIS Normal Operating Water Levels H.W.L. = 142.60 T.W.L. = Normal Operating Water Levels with Earthquake Water Level same as Case I Horizontal acceleration due to earthquake is 0.20 g in the downstream direction Normal Operating Water Lezvels with ice H.W.L. = 142.60 T.W.L. = Horizontal Ice Force at 5 k/ft. Zero Freeboard H.W.L. = 147.60 T.W.L. = Probable Maximum Flood H.H.L. = 154.10 T.W.L. = Q 16,000 cfs PLATE C-1 EL. 142.60 -'5iZ --I -------7--~-----------' -----= ~---·---~-~~ .... . ROCK FILL ~ // ~ . :I: + L __ --'AR 33.00' PELICAN COVE CREEK DAM-WOOD CRIB DAM LOADING CONDIT10N NORMAL CONDITION HW=22.0 EL. 141.60 0 EL. 120.60 :>:::FH = 15. :>:::FV = 59. :>:::FH/:>:::FV =0.25 SSF = 2.75 RESULTANT AT X = 1 8. 7 ECCENTRICITY= 2.19 :>:::MR = 956. :>:::MO = - 1 1 1 • :>:::MR I :>:::MO = 8. 6 5 BASE STRESS (PSil 7. AT X= 0.0 17. AT X= 33.0 ~ 10 S c ale in ft • t ·~ WOOD CRIB SPILLWAY SECTION ANALYZED FOR STABILITY ALASKA DEPT. Of' NATURAL RESOURCES DIY. Of' LAND AND WATER WANAGEWENT un l't:ll. 28, IM5 3t4~ 2 c-2 CI.IC•r 111 "au fMAI~ CIHO:J EL. 1~4.10 ·----------~ I EL. 142.80 ----• - -.j ~ -+l . H~ ROCK FILL + r---~~ L_. f ___ _ C o R A-~-----''~r·'===!i·l-----------f-J noo' _j PELICAN COVE CREEK DAM-WOOD CRIB DAM LOADING CONDITION PMF COND. HW=l 1 .50' ABOVE CREST EL. 141.80 EL. 120.80 :CFH=31. :CFV = 88. :CFH/ :CFV = 0. 35 SSF = 1.99 RESULTANT AT X = 20. 5 ECCENTRICITY = 4.01 :CMR = 1384. :CMO = -285. :CMR/:CMO = 4.86 BASE STRESS <PSI l 5. AT X= 0.0 32. AT X= 33.0 0 5 10 Scale In he t ·~ WOOD CRIB SPILLWAY SECTION ANALYZED FOR STABILITY ALASKA DEPT. Of NATURAL RESOUACES DIV. ~ LAND AND WATER MANAGEMENT rMAIN1 CIH03:...:.J I -------••n r-~D. ZI,IN5 Clll., ,.. , ..... lt45 2 c-3 SlABILI 1'( SUMMARY CONDIT ION BASE :FH :FV lfH s Ktl>JJ_l) AN I J lh 1 Mo )_Mil_ BASE STRESS (psi) TOT LEN CR LEN·-r-EFFLE-N I~ 1 n l ( K1 PS) :fv •-f I DOW~~?~t AM (k-r 1) I 1-FTl ) ~·· UPSTREAM DOWNS I RUM CAS!:: I n.uu JJ.UU 15. ~9. 0.25 2. 75 14. H 960. 110. 8.65 7.5 1 7. ,, CASE ll JJ.Ull J:I.Oll 2o. 5Y. 0. 4 -j 1. o2 u.uo %0. 190. .>.09 4.5 20.J CASte 111 n.uu JJ. ()() 20. SY. 0. J4 2 .oc. ll • .J4 1J6U. lLU~ 4.4.:. J.'> 2!.4 CAS!:: lV JJ.OO JJ.OO ll. 66. ll. JJ 2.11 1 J. Y7 lllU. 190. ).')] 7. 5 20.) CA~E V JJ.UU JJ.OO ll. 88. U.J) 1.99 12.49 uso. L85. 4.H6 5.0 J2.1J l'EI.l CAN COVE CltEKK ilAH S'I'AlllLl TY SUHHAJ: ~ ALASKA DEPT. Of NATURAL RESOURCES DIV. Of' LAND AND WATER MANAGEMENT ~\AI~ taU fEB. 28,1985 (.t ••• , ... HUt u~oa '3945 2 - APPENDIX D INSPECTION CHECKLIST .. UNSAFE DAM REPORT FOR~! a. Name: b • ~: Tin-, b e ,-C v 1 b j Ti ......., h tt ,--13 v iT r ~ 5 .J c. I. D. No.: ,4 /<..' () oo 33 d. Height: ~ ~ t:t- e. Hazard: L Hfi!v~ e.:{l.;~_f e. f. Size: S J¥J 4..1/ g. Location: State: County: Nearest D/S City, Town or Village: River or Stream: /-. / C k ..., e t c.. ,, .., Y e. e. h. Owner: I:;) e.. I L '"'4"-_, u f d d· y c d ""'"'p ~ .., '::l i. Condition of Dam Resulting in Unsafe Dam Report: n. Remarks: Signature: ~ ~L) J ;:L ?! Date : AJ .. -v-3 0 1 I L 8': "f 7 • • 1. 2. 3. 4. s. VISUAL INSPECTION CHECKLIST Name of Dam; PtJ../JC .. o ..., C .. •.·c. C yu k Inventory No.: A/<. o oo 3 9 Hazard Category: ifiJ i~Y~e~JJ ... ~e.. Size Classification: ~'"41/ Owner: pl!.f 1 c..~' "" Pe.J1cr:•.., U r 1 i J1·1 C c.,.,.. p•"' '1 AJ~sk.t:\. <J983;( w a. It-C o f A sr" , p /t:~. ... f /?~ .., "",~ ~ r: Pe.h ~.., s~ ... 'l·c-•'..1 ~ r ~~~ c.. (Jeflc.-..,.,1 A/ajka.. J9c'i3~ 6. 7. 8. 9. 10. Inventory No. A j;oo 0 3 '3 Sheet ~ of ~ Date Inspected: /l}c•r.' .301 1.?8~ Pool Elevation: I 38 ,C f Tailwater Elevation: 11../c, c. c.. f 0 c. ....._, Purpose of Dam: Pc;#t ...-/u'o: Jr v 5.-/'I'J y Weather: 3 ..1 ,.,:.. -t=J,_.yne.:;, "'"'(....J,., !)Jot~.v _, ....... ~~-... ~ .... / .:t.+-Oc-. .,jti<:. Directions: Mark an "X" in the "YES" or "NO" column. If item does not apply, write "N/A" in "REMARKS" column. Use "Other Comments" space to amplify "REMARKS". ITEM YES NO REMARKS .. Inventory No. _ _.Ac.~.· ,.:..;k"'--=0-=0::...0~3~3 __ Sheet __ a__;__ of -----"'-1" __ ITEM YES NO REMARKS -- TH!BER DANS TYPF:: T;..,J;,.,.. c ,.,-,b ~ !'JvHv( '> '> 1. CREST a. ~ Settler:1ent? _ _x. ----,-- b. Any Hisaligt},s_ent? "' h• .,.,.,-Q{.,~ Sf!r'<-..._ S<: Ill~_......_+ ~t~J<..:-/<~.· r----·-£--. N f:.--;..., < ,...,.;;: c. Adeg__'-;!ate Freq_!:oard? r'ETr.H: ~o~ I r-A7.. - d. Deck Timbers Sound? J( _j.,....., (.., r,r, Chtt<K~ T /$._.,.,/<,. <!.. --... 2. ABUTHENT & FOU::DATION CONTACTS ---. a:-An~--F:~;-s i-on? X 0 ''(.. +--J~tll~ C-+·:~_1':> ( .,..,_ r) 1-x --~·--· ___ _!;,_. S.e.l;~<.!&~...J:.r~s_ent? ;(--·--- t· c 'B o i l_!L__Q _.r_S_p r i_ ru::_s Downstrean? d. ExDosed Bedrock? )( -- ---~~e_Q_r:.ock Det_~_riorated? -X __ __L. ___ V..is_lbl!!._P_i_s_p~la·:e..:::e.n.t.~? _A~---r ----- r--------·---I ! 3. STRUCTUlC\L & CRIP. TI:m:::RS c-§ '---~---------------~------------- ___ a,_._ 1.\!!.:LJI.e:. t e r t_ QI:: ti 0 n? ;( __ -!-----.. e -;,p~c.l .. flr. Q;.... C • -" #He -11..,.. ) b. Are I.J~~~--Brog;::~_:t_.QE.__J;hes.~.:f'd? __ I{ _1___ . ~-------- c. Ar Ti.::-:2.~rs_l'J:.~q_g_plati_ve_ ~r_rc~ated?_l...... . _]{__*J'</Io<V C ••/.< Y ___ , _________ ~ ------~__}xg _'j;',l;::~ b~_rs~:iw~e_Q_QJ.:_B.Qlt;,.ec~? ___ -~ ______ I -------- • 4. C'tiBS ·-I- _ ____a_,__ALC.._ G.ti b.s.....l'J. 11 e c' ; : i t' h P,... r lr 1' i 1 "' ? ;( ,< cH k. ~Ill I) llh."'"'' ...... ld;. J I' P~ lu iA..I b. lL!iGJOkfULC'."·-' , __ ,., .~-± T'<J,f. of:. Do""""\ f--.-.. - 1-----· ' - --·----~~---- ---1-------- ------- ------ --------- ~"------ -~---------1----i -------, • Other Comments: Inventory No. A J< 0 0 0 3 9 Sheet 3 of 5"" ITEM YES NO REMARKS SPILLWAYS TYPE: ()t: t .,..7!.-,v /3o .. / Cn•-. hi We iv- " __.L_ CRES.:r TYPP.: T1""" bo .bY"-·.· ./c.~ s.l"'·r a. Any Set t Le_M~nts? ~- b. Any Mi~?_U.&..nments? ;< - __ c_. __ ArrJ_Cr ac kj. DR1 7( d. A_~teJ;:,ioration? ;( 5 c;I""J ~ Y"'-' f-+ cJ.~, 1<~ ·- e. Ex_p_Q.s_e_ct_Rc i nfo~emcn t? Nil------- f. EroQ.i_Q_rl] X. -- _ _z. __ Si.lt_D_e p.QS it Upstrear:J.' ;< 5,/t '"'1 u 5 F<~., .,._.; f=..,.,,.~ f-O.:J,.,) .... L2_._C.Q(1T.RQL__S IJWCTUR E S TYPP.: 1-); ., '-NO. 1\.')'¥~- ~echanic~l EquipMent Onerable? --A.l/.A-- ~----- b. Are G<!tes Haintained? ------ _ __c__.__jli_l__L__f_l_a__s_h_b oar d s_]'r :l p Automatically? ... ------ ~d~__tancl1ions IrinQable? __ e.~ __ .A.r___e....Gue.s._Re.mo t e 1 y CQ.ntm.lle d? y ~-CHU.IE TYPE: }.Jc .. e. __ a..___Anv Cr acJz.in_g..?___ ---~-J.J/A I -- _ _Q_. _ __A!_ly Deterioration? I -------- , r-----c. Er o si.Qll'L_ --···- r----_ _d_.___Expo _ _s__e d_R_~in.f..llr~_e n t ? .------±=~ r> ~ep__age____at Lift Li p._e_£_Q.r:....JQJ..nt. ? ~_ll;'ERGY DISSUb'T'G"Q~ ~---ITYPr: ~~-'1<!. d.').,J...-.. J"-t-R..t ~<-:'.2 -"!. ~_n~rioratjon' -------; A) ltt-() "'-~.,.jv~ c k., ~h_._____L.r.os i .-... n? ---- r------_c_.~_us__ad__l'~i.nf.o rr f>r" P n r-? 'j 5. ~lEIAL A££;JgTf.tJHTr.Fc:: /1.) ,; "' <.. ::0 r..-....rr.a_c:i '.n? IV/_!} h Rr£>,qkag-p? ,]--- ~c._._Sc_c_ur e tmcborages' ~...._________B_fERGE.HCY.___S.EI.LLtJ A V TYPE: ).),'11!.. ~.a.. Adequa t.e........Grass c ove.r_? A1 I f). "h ....._c}_e_ai:_.A.p pr a a c b Chann.-.1? -----, r--.C. ,__Er_o_di.bl e Down.stream c b .:lililf: 1 ? ---- 1--_!L__Er..o.di h] c E11se .Elllg_? . ----· &> ~ r-r>. h 1 e....$._i_d e_Slo_ n&> c: ? ., - -- -- -------- Other Comments: • Inventory No. _ __..A~k~_,.0'--'0""--=0 __ ,_,3:....:3==---- Sheet 1 of 5" ITEM YES NO REMARKS --LOtJ LEVEL OUTLET TYPE: 1. GATES A//1} --~~~~~-~--~~--~~~-----~----+-----~~~~------------------------r----a~·~H_e_~c~h~a~n~i~c~a~l __ E_q,~u.~i-~p~rn_e_n~t~O~r.~e~r~a~b~l~e~?~----+-----4~----+-----T4-'----------------------------~ ~-----b_.~A_re Gates Re~~o_t_e~l~y~C~o~n_t_r_o_l_l_e_d __ ? ______ ~-----+----~~--~----------------------------~ c. Are Gates Maintained? ·-2--.--c-o-NCR-'E_T_E __ cO_N_DulT~s~------------------------~----~----~~---4-------------------- ____ a_._~ny Cracking,?: ________________________ -+-----4-----~~----~--------------------------~ ----~b_._A.~~eterioration? c. Erosion? ~-----------~--~------------------------------~--------~~----1---------------------------~ ___ d~~-~osed Reinforc.~i~n~g?~----------------~-----l-------+-----~---------------------------4 t-----e_. __ Ar e Joints Di ~ p=l-=a-=c-=e:..:d:...:?~---------------1------J--·-----4------+---------------------------~ ~-f. Are Joints Leaking? ~HETAL CONDUITS ____ <!·_l~t!g_~al CQ.rroded~? _____________ ~~---!------~f-----+---------------------J !--__ b_.!_ls_Cond ui t C r acl<,..,c::,d:!...!...? ---------------+-----l----_ --t----+----------------------1 __ -~6I~ Joints Di sn.l.,_a"""'c""'e_d...,~? ____________ -+----___ ---J.------1~---------------------1 ,---d_._A_r_g_J'_Q_i n ts Le c1 king_.;_? ______________ -+---------•-----+-----------------------t _!:~__E.:IERGY DIS SIP AJ:_Q'-'R,_,S,_ _______________ +---·---+------t----+---------------------; _ r----aLA.flY De t e""r.__i""o~r'-"a-"t""'i"'o""n,__,?'------------------~---~---------_____ ..___ _________________ -------1 b. Ero~ion' -r-----~1-----4-----------------------~ ----~~_ExP~sed RPinforc~~G··~e~n~t? _________ -4----~---~-----+--------------------~ ~--l:ll~--~~PPJlRTf._N'"".,_,A._,_,_N"'C-'-'E~S.,'---------------------~-----t-----,---f---------jf----------------------------1 a. Corrosion? b. Break£ge~? ____________________________ -+-----4~----+-----~----------------------------1 f.--c.. Secure Anc.hora?es? ' ~------------------------------------------~----+-----4-----------------------------------l ~---------------------------------------------4----·-4----~------------------------------l Other Comments: • Inventory No. --L.A,.__k..;:.....;o;....o_:__o--'3:::..-"-.J __ _ Sheet · £ of ---e.?-__ ITEM YES NO REMARKS INTAKES }. EQUIP~E_NT a. Trash Racks? X b. Trash Rake? ;( -c. Mechanical E~lrmcnt Operable? ;<. ·----- d. Int~ke Gates? 1\ __ e. Are Racks and Gates Haintainerl? -·4 ----------- f. Arc Gate O£lerators O_eerable? 2. CONCRETE SURFACES a. Any Cracking? N 1/.J b. Any Deterioration? ,.__ c. Erosion? --d. Exposed Reinforcement? - e • Are Joints Displaced? ----- f. Are Jo ill.t;S Leak 1 nz? .. I - 3. CONCRETE CONDUITS -------·~~-------~P ----· ~·-Any Cracking? ----·------ ___ 1.!.~'\!!Y..Jl.? t_~ rio r a t ion ? ------ c; _ _! __ ~ro~,ton? _...JL__E_xposed f:.e in f n rc~~en t? -·-~-... ~ .. --·----- r-----e. Are Joints Dis_p_laced? . ,___ ___ f .!.....Are J_Q_i n t s Leaking? 'I 4. i1ETAL cor;DUITS a. Is Metal Corroded? iJ7A b. Is Co."!lduit Cracked? c. Are Joints Di S.J?.lac ed? d. Are Joints Leakink!? 5. METAL A_I'_PURTErTAJ'iCES a. Corrosion? J{ -- h. RreA.kar>e? X. C• Secure_6._QChQ..rage_§? t:.. . 6. PENSTOCKS .. ·--TYPE ~!ATERIAL: Ttl1.b.~ pJ.,.,.,<.t-{,l.h .. / __ 1!.! _ _11 at~ r:: i ~_.1.__.12~ t e _r_i_ o_r..E~ r-9.? X.. --Z.,.;... t cJ.~c.k/..:..=:; f>,t:_(.. ~_____l:?~Q i l}_tc? _Le_qls:_i.Dzl _____ ;(.. lt:.-. J<~.,<!.. j,,.':> b.,..:._ 1-JIIY~..J b"\ ;. "11"'-<... ·-----· c. SJ.UlllQL.tL~..QJtat;_e? X s4 .... C.. defCY"l<-¥..../-1-\ - ___ .Jl.,_..An.ch o t:Jl oc k.s_.S_t_q_bl~J ·--~~~-------- _, -- Other Comments: .. • Iii PART I -INVENTORY OF DAMS IN THE UNITED STATES (PURSUANT TO PUBLIC LAW 92-367) See te\·erse side lor instructions -·----······------ Ill Ill 141 lSI (61 171 181 191 H"ME FORM APPROVED OMB NO. 49--110421 REOUIRflolENTS CONTROl SYIWIOL DAEN-CWE-17 IIO I L" TITUDE (North) 1111 LONGITUDE (We.st) • • Ill ... IDENTITY ,._ ... HUMBER !;; •h 3)•1si6J7 ~~A o~jo~,l> 1121 REPORT taTE --•-·· i_i I I II I I II I I IiI I I I I I I I I I I I I I I 1 i 1 i 111 I j l iII i-l_l_j_1 j __ c.I_LL._l_L_f __ l JDEHTIFIC.A.TJCJot 1 , 1 1 r 1 1 , 1 ~.-1 v 1 , , I"' w 1 (Ill 1141 POPUL"R IUME H"ME OF IMPOUNDMENT ID~~J~~~c:!~OH~ I I .1 I .I_. I .I_, I _j .1..1 __ , _L.t..L L L L_L_L::J .L_L_L_I :IuL_L_t __ I._L.L i.J ... _. L f._J. L_L.L::J __ L_L_L_I__f _.__,uL.t _.__. __ • _.__.uL_I__L_L_L_i _L_L_L_I .__.__L~I (lSI 1161 (171 (181 1191 1201 RIVER OR STRE"M POPUL"TIOH LOCATION STATISTIC$ 1281 REMARKS ENG 1 ~~~11 4474 • • STATISTICS MISC DATA MISC. DATA (C onrinued) MISC. DATA (Continued) REMARKS ENG FO ... 1 Ot:C '11 • ~~~ PART II INVENTORY OF DAMS IN THE UNITED STATES (PURSUANT TO PUBLIC l.Ail' 92-367) (291 110) (31) (321 .. ... lC "' ' 0 4474A 1491 ~- SPILLWAY 1461 OWNER Sec reverse sule for Instructions ---~ ---~ -~~---- (33) (HI IHSPECTIOH BY 1341 VOLUME Of DAM (CY) (SOl (3S I (36) (371 (38) POWEll CAPACITY (471 ENGINEERING BY (541 IS6 D • • Ill "' FOI!M AI'PIIO\IfD ... IDENTITY • HUMBER OMBNO.~I .. "' IIEOOIREM£NTS CONTROL SYMBOL tp: 314151617 DAEN-CWE-17 ~~A cl ~~b; 1~ ··--------~-- 1191 (40) (411 (42) (4ll (441 (4SI IUYIGATIOH LOCK$ (48) CONSTRUCTION BY (Sll tnt (sst AUTHORITY FOR INSPECTION