1982 Proj Operations 1983 Colorado River Basin

Home , Fontenelle Dam

12th nnual Re rt Operation of the C v Basin 1982 Proj Operations 1983 Colorado River Basin

Wyoming

Nevada Colorado

New Mexico Contents U.S. Department of the Interior

Bureau of Reclamation

January 1983

(Prepared pursuant to the Colorado River Basin Project Act of 1968, Public Law 90-537)

cableway holst at Hoover Dam. Sprinkler Irrigation.

Introduction...... ~ Authority for Report .... "...... 2 Actual Operations Under Criteria· Water Year 1982 2 Projected Plan of Operation Under Criteria· Water Vear 1983 3 Determination of "602(a) Storage" ...... 3 Mexican Treaty Obligations ...... 3 Regulatory Wastes...... 4 Projected Plan of Operation· Water Vear 1983 5 Upper Basin Reservoirs Fontenelle Reservoir (Green River) ...... 6 Flaming Gorge Reservoir (Green River) ...... 8 Wayne N. Aspinall Unit- Blue Mesa, Morrow Point and Crystal Reservoirs (Gunnison River) 10 Navajo Reservoir (San Juan River) '.' 12 lake Powell (Colorado River) 14 lower Basin Reservoirs Lake Mead (Colorado River) 16 Lake Mohave (Colorado River) 18 Lake Havasu (Colorado River) 20 River Regulation 22 Flood Control ...... 23 Beneficial Consumptive Uses Upper Basin Uses and Losses 24 lower Basin Uses and Losses 24 Water Quality Operations 25 Environmental Programs Upper Basin 26 Lower Basin 26 Power Operations Upper Basin-Colorado River Storage Project 28 Major Maintenance Activities 29 Lower Basin 30 Major Maintenance Activities 31

1 Introduction Authority for Report Actual Operations Under Criteria-Water Year 1982

:;/ Granite Reef Aqueduct. Taylor River above Blue Mesa Reservoir. Pipeline at Havasu Pumping Plant.

The operation of the Colorado River Basin Pursuant to the Colorado River Basin Project The initial plan of operation for water year during the past year and the projected Act (Public Law 90-537) of 1968, I am pleased 1982 was based on an objective minimum operation for the current year reflect flood to present to the Congress, and to the release of 8.'23 million acre-feet from Lake control, domestic use, irrigation, hydroelectric Governors of the Colorado River Basin States, Powell. With this release, and assuming power generation, water quality control, fish the twelfth annual report on the Operation of average inflow conditions, the projected active and wildlife propagation, recreation, and the Colorado River Basin. storage at Lake Powell would have been less Colorado River Compact requirements. than the active storage at Lake Mead by This report describes the actual operation of September 30,1982. Storage and release of water from the Upper the reservoirs in the Colorado River drainage Basin reservoirs are governed by all area constructed under the authority of the Beginning in ApriI, however, the forecasted applicable laws and agreements concerning Colorado River Storage Project Act, the most probable inflow to lake Powell was the Colorado River, including the Boulder Canyon Project Act, and the Boulder above average, and the scheduled release impoundment and release of water in the Canyon Project Adjustment Act during water from Lake Powell was increased to 8.6 million Upper Basin required by Section 602(a) of year 1982 and the projected operation of these acre-feet in order to equalize storage with Public Law 90-537. The operation of the reservoirs during water year 1983 under the Lake Mead by the end of the water year. This Lower Basin reservoirs reflects Mexican "Criteria for Coordinated Long-Range plan of operation remained in effect until Treaty obi igations and Lower Basin Operation of Colorado River Reservoirs," mid-June when the inflow forecast was contractual commitments. published in the Federal Register June 10, revised downward. The revised forecasted 1970. inflow would have placed the projected active Nothing in this report is intended to interpret storage of Lake Powell below lake Mead even the provisions of the Colorado River Compact James G. Watt, Secretary with a minimum objective release of 8.23 (45 Stat. 1057), the Upper Colorado River United States Department of the Interior million acre-feet. Basin Compact (63 Stat. 31), the Water Treaty of 1944 with the United Mexican States (Treaty Series 994,59 Stat. 1219), the decree entered by the Court of the United States in Arizona California, et al. (376 340), the Boulder Canyon Act (45 Stat. 1057)1 the Boulder Project Adjustment (54 Stat. 774; 43 U.S.C. 618a), the (70 Stat. Projected Plan of Operation Under Criteria- ater Year 1983

Davis Dam turbine runner Inspection. Headgate Rock Dam. Transformers.

The consequences of readjusting the plan of Determination of "802[a] Storage" failure to store sufficient water to assure operation late in the water year were Section 602(a)(3) of the Colorado River Basin deliveries under Section 602 (a)(1 ) and (2) of considered; after discussion and consultation Project Act of September 30,1968 (Public Law Public Law 90-537. with interested agencies and groups, 90-537), provides for the storage of Colorado scheduled summer releases were reduced ill River water not required to be released under Taking into consideration these relevant order to meet a minimum objective from Lake article III (c) and III (d) of the Colorado River factors, the Secretary has determined that the Powell of 8.23 million acre-feet. The actual Compact in Upper Basin reservoirs, to the active storage in Upper Basin reservoirs inflow into Lake Powell during the summer extent the Secretary of the Interior (Secretary) forecast for September 30,1983, exceeds the months was considerably greater than the finds it necessary to assure compact deliveries "602(a) Storage" requirement under any forecasted inflow. As a result, by September without impairment of annual consumptive reasonable range of assumptions which might .30, 1982, the active storage of Lake Powell uses in the Upper Basin. be applied to those Items previously listed. was 23,005,000 acre-feet and the active Therefore, the accumulation of "602(a) storage at Lake Mead was 22,766,000 Article II of the' 'Criteria for Coordinated Storage" is not the criterion governing the acre-feet. Total release from Lake Powell Long-Range Operation of Colorado River release of water during the current year. during water year 1982 was 8.30 million Reservoirs" (Operating Criteria) provides that acre-feet. the annual plan of operation shall include a determination by the Secretary of the quantity During water year 1982, the water supply in of water considered necessary to be in Upper Mexican Treaty Obligations the Colorado River Basin was approximately Basin storage as of September 30 of the 111 percent of the long-term average, ranging cu rrent year. Annual calendar year schedules of monthly from 132 percent for the Green River above deliveries of water in the limltrophe section of Flaming Gorge Dam to 100 percent for the This determination shall consider all the Colorado River, allotted In accordance Gunnison River above Blue Mesa Dam. The applicable laws and relevant factors including, with the Mexican Water Treaty signed in major storage reservoirs in the Colorado River but not limited to the following: (a) historic 1944, are formulated by the Mexican Section Basin stayed within the normal operating streamflows; (b) the most critical period of and presented to the United States Section, range during water year 1982. Aggregate record; (c) probabilities of water supply; (d) International Boundary and Water Colorado River system storage at the end of estimated future depletions in the Upper Commission (Commission), before the the water year was 54,029,000 acre-feet, Basin, including the effects of recurrence of beginning of each calendar year. representing an increase of 4,456,000 critical periods of water supply; (e) the acre-feet from the previous year. By the end "Report of the Committee on Probabilities of the water year, active storage in the system and Test Studies to the Task Force on was approximately 96 percent of the January 1 Operating Criteria for the Colorado River," maximum available storage. dated October 30, 1969, and such additional studies as the Secretary deems necessary; (f) the necessity to assure that Upper Basin consumptive uses are not Impaired because of 3 Spectacular Morrow Point Dam. canal excavation -1935. Upon 30 days advance notice to the United Regulatory Wastes States Section, Mexico has the right to Deliveries to Mexico consist of river water modify, within the total schedule, any monthly delivered to Imperial Dam and waste and quantity prescribed by the schedule by not drainage return flows from water users below more than 20 percent. During water year Imperial Dam. In addition to assuring normal 1982, Mexico received a total delivery of about water del iveries, the small amount of 1,412,000 acre-feet at the Northerly regulatory storage space in Imperial, Laguna, International Boundary. and Senator Wash Reservoirs was used at times to limit potential downstream flood Of the 1,412,000 acre-feet of mainstream damages. during water year 1982. Regulatory Colorado River water reaching the Boundary, waste for water year 1983 will depend on the about 1,600 acre-feet was delivered through actual hydrologic conditions occurring during Pilot Knob Powerplant wasteway from the that time. All-American Canal. An estimated 352,000 acre-feet was released through Laguna Dam. The remainder of the flow at the Northerly International Boundary was made up of return flows to the Colorado River below Laguna Dam, and returns to the Gila River below the gaging station near Dome.

Because of the current water supply conditions, the United States will make scheduled deliveries of 1,700,000 acre-feet of Colorado River water to the Republic of Mexico in calendar year 1983. This release of water is based upon average runoff conditions for the year. Should the runoff in water year 1983 be substantially above average, significant releases for flood control purposes could be required from Hoover Dam. Representatives of the Republic of Mexico will be kept informed of operating schedules through the United States Section of the Commission. 4 Projected Plan of Operation Water Year 1983

Canal excavation -1983. Inspection of Hassayampa discharge line. A proposed operation plan for water year 1983 The projected operation for average runoff for the Colorado River reservoir system was conditions for each reservoir in the Colorado formulated and distributed to representatives River Basin for water year 1983 is described in of the Colorado River Basin States during the following pages. Charts 1-8 show the October and November 1982. The plan was projected monthly outflows from each prepared in accordance with the Operating reservoir for four assumed hydrologic Criteria published June 4,1970, in compliance conditions. Each condition reflected the most with Section 602, Public Law 90-537. The plan current hydrologic information available by reflects operation for flood control, domestic including actual forecasted October and and irrigation use of water, hydroelectric November 1982 inflows. Inflows for the power generation, water quality control, fish remainder of the year were based on the and wildlife propagation, recreation, and following assumptions of 1983 modified runoff Colorado River Compact requirements. from the Basin: (1) average based on the 1906 1981 record of runoff; (2) upper quartile based The plan calls for a minimum objective release on the annual level of streamflow which has from Lake Powell of 8.23 million acre-feet been exceeded 25 percent of the time during under lower quartile inflow conditions, or less. 1906-1981; (3) lower quartile based on flows Under most probable to upper quartile inflow exceeded 75 percent of the time during 1906 conditions, the scheduled releases from Lake 1981; and (4) most adverse based on the lowest Powell are projected to range from 9.6 to 12.0 year of record, wh ich was 1977. million acre-feet in order to equalize storage with lake Mead by the end of September 1983.

5 Upper Basin Reservoirs Fontenelle Reservoir [Green River]

Fontenelle Dam and Reservoir. self propelled sprinkler system, Yuma Mesa. Water Year 1982 Water Year 1983 Fontenellei Active Storage'" Chart 1 Fontenelle Reservoir is operated for power At the beginning of water year 1983, the generation, water supply, flood control, fish elevation at Fontenelle Reservoir was 6504 Reservoir (Acre-Feet) EI.(Ft.) and wildlife enhancement, and recreation. feet with a content of 326,000 acre-feet. 6506 The water surface was gradually lowered from Releases from the reservoir, assuming Maximum Storage 344,834 6491 an elevation of 6493 feet at the beginning of average runoff conditions, will be scheduled Rated Head 233,789 6485 the water year to a low of 6480 feet in April to draw the water down to 6479 feet prior to Minimum Power 194,962 1982. The reservoir filled at the end of June the spring runoff. Surface Area (Full) 8058 Acres and remained essentially full through the Reservoir Length remainder of the water year. During October, the reservoir was drawn (Full) 18 Miles down 13 feet in order to investigate the cause Power Plant The minimum release during the fall and of increased seepage a,ong the left abutment. Number of Units 1 winter was 400 cubic feet per second (cfs). A drilling and test program is being conducted Total Capacity 10,000 Kilowatts The maximum release for the water year was to determine whether remedial action should *does not include 563 acre-feet of dead storage 13,280 cis. The maximum inflow of 13,060 cfs betaken. below 6408 feet occurred on July 1. The minimum release for power generation is 500 cfs; the maximum The maximum release from Fontenelle release through the powerplant is 1,750 cfs at Reservoir is dependent primarily on the rated head. A total of 1,629,000 acre-feet was magnitude of the inflow. If the inflow is in the released from the reservoir with 796,000 upper quartile, peak outflow is expected to be

acre-feet bypassing the powerplant. less than 10 JOOO cfs. With an average inflow, the anticipated peak outflow is less than 5,000 cfs. Assuming a lower quartile inflow, the outflow will probably be no greater than 3,000 cfs.

6 sampling of fish populations. Harmless Chukwalla.

Outflow Release In 1000 Cubic Feet/Second Storage Actual Operation 1982 Usable Content in 1000 Acre-Feet Elevation (Feet) Non-linear Scale 9 8 7 6 5 4 3 2 t---+-~----+--+---+----t-+- 1

Projected Operation 1983 Upper Quartile 6 Sf---4----+--I--4---f--'--I---.-- 4 3 2 1

Average °ONDJ FMAMJJ ASONDJ FMAMJ J Actual 1982 Projected 1983 3 2 1

Lower Quartile Legend 3 ~-+---+---+-+--+--+--lr----:±:--+--+-t---t Most Probable 2 Upper Quartile 1 Lower Quartile Most Adverse Most Adverse ••••••••••• 4 3 2 1 o N 0 J FMAMJJAS 7 Flaming Gorge Reservoir [Green River]

Transformer under construction.

Water Year 1982 Water Year 1983 Flaming Gorge Active Storage* Chart 2 At the beginning of water year 1982, the During water year 1983, the reservoir level at reservoir water surface elevation was 6018 Flaming Gorge is projected to be drawn from Reservoir (Acre-Feet) EI. feet with a content of 2,913,700 acre-feet. 6036 feet to about 6024 feet before the spring (Ft.) Prior to the spring runoff, the reservoir of 1983. The water level will remain high elevation was drawn down to 6010 feet. The enough under any inflow conditions to launch Maximum Storage 3,749,000 6040 April through July 1982 runoff above Flaming boats from the reservoir's nine ramps. Rated Head 1,062,000 5946 Gorge was 1,458,000 acre-feet, 126 percent of Average inflow would result in a maximum Minimum Power 233,000 5871 the long-term average. With this runoff, the elevation of 6035 feet with a storage of Surface Area (Full) 42,020 Acres reservoir reached its seasonal maximum 3,546,000 acre-feet during July. Reservoir Length. elevation of 6036 feet with a content of (Full) 91 Miles 3,590,600 acre-feet by mid-August. This Due to high carryover storage and scheduled Power Plant approximate elevation was maintained work on the spillway, releases from Flaming Number of Units 3 through the end of the water year, and by Gorge will be higher than average in water Total Capacity 108,000 Kilowatts September 30,1982, the elevation was 6036 year 1983. Flow in the river below the dam, *does not include 40,000 acre-feet of dead storage feet with a content of 3,572,300 acre-feet. however, is not expected to exceed 4,000 cfs below 5740 feet or to fall below 800 cfs. The normal minimum release at Flaming Gorge Reservoir is 800 cfs. The maximum release through the powerplant is 4,600 cfs at rated head. During the water year, a total of 1,257,000 acre-feet was released through the powerplant.

8 Outflow Release in 1000 Cubic Feet/Second Storage Actual Operation 1982 Usable Content in 1000 Acre-Feet Elevation in Feet (Non-Linear Scale)

3t--+--+--+---+--+---+---+--I---+-+---I----I 3749 ...._~-I--+--+---+_J---+---+-----+--+- ___ 6040 2 1----1---4-----1-- 1 6021 Projected Operation 1983 Upper Quartile 6000 4 3 2

Average 4 ~--t--+----It---t---+---+-+---,-,--+----+----+--+----1 3 2 1 ONDJ FMAMJJ ASONDJ FMAMJJ Actual 1982 Projected 1983

legend Most Probable Quartile Quartile Wayne N. Aspinall Unit [Gunnison River] Blue Mesa Reservoir Morrow Point Reservoir Crystal Reservoir

Blue Mesa Dam on the Gunnison.

Water Year 1982 Water Year 1983 Blue Mesa Active Storage* Chart 3 The Wayne N. Aspinall Unit, formerly the Assuming average inflow for water year 1983, Reservoir (Acre-Feet) EI.(Ft.) Curecanti Unit, includes Blue Mesa, Morrow Blue Mesa Reservoir is expected to reach a Point, and Crystal Reservoir. Blue Mesa low of 7463 feet with an active storage of Maximum Storage 829,523 7519 provides nearly all of the long-term regulation approximately 392,000 acre-feet in March. Rated Head 249,395 7438 for all three powerplants. Morrow Point The reservoir is projected to fill to its Minimum Power 81,070 7393 provides peaking power, and thus has highly maximum storage of 829,000 acre-feet at Surface Area (Full) 9,180 Acres variable releases. The primary function of elevation 7519 feet. Reservoir Length Crystal Reservoir is to reregulate the variable (Full) 24 Miles Morrow Point releases. Morrow Point Reservoir will operate at or near Power Plant its capacity during the current year. Crystal Number of Units 2 At the end of September 1981, Blue Mesa Reservoir will also operate nearly full except Total Capacity 60,000 Kilowatts Reservoir contained 376,100 acre-feet of for daily fluctuations needed in regulating the *g~~swn~~~~1~~e 111,232 acre-feet of dead storage active storage with a water surface elevation releases for Morrow Point and to meet ~orrow Point Active Storage* of 7461 feet. The April through July 1982 downstream requirements for fish habitat and Maximum Storage 117,025 runoff above Blue Mesa was 742,000 diversions through the Gunnison Tunnel. 7160 Rated Head 79,805 acre-feet, 96 percent of the long-term 7108 Minimum Power 74,905 average. The total water year runoff of Assuming average runoff conditions, releases 7100 1,070,000 acre-feet was approximately equal from Crystal Reservoir will be maintained at Surface Area (Full) 817 Acres to the long-term average. The water surface powerplant capacity of about 1,600 cfs. Under Reservoir Length (Full) elevation of Blue Mesa reached a maximum of lower quartile runoff conditions, releases will 11 Miles 7509 feet in June 1982, with a content of range from the minimum of 1,000 cfs to a Power Plant Number of Units 2 739,100 acre-feet. No water bypassed the maximum of 1,700 cfs. If the inflow is above Total Capacity 120,000 Kilowatts powerplant during water year 1982. average, it will be necessary to bypass the *g~~wngAJ~1~e~e powerplant. 165 acre-feet of dead storage The drawdown for power operations and river Crystal Active Storage* regulation was great enough that no further Maximum Storage 17,573 6755 space evacuation' for flood control was Rated Head 13,886 6742 required. During water year 1982, all flows in Minimum Power 10,619 6729 the Gunnison River below the Gunnison Surface Area (Full) 301 Acres Tunnel were greater than 200 cfs, the Reservoir Length minimum discharge required to protect the (Full) 7 Miles fishery in the river. Power Plant Number of Units Total Capacity 28,000 Kilowatts *does not include 8,200 acre-feet of dead storage 10 below 6670 feet Crystal Dam. Mesa Trail at Morrow Point.

Outflow Blue Mesa Reservoir Storage Blue Mesa Reservoir Actual 1982 Release in 1000 Cubic Ft/Sec Usable Content in 1000 Acre-Feet Elevation in Feet (Non-Linear Scale)

2t---+---+---+-+---+--+---+-t---+--+---+---I 900 <.r%%:h 830: ... ..7519 800 >>>>>=.. 7516 1 .. :::> . Projected Operation 1983 700: 7505 Upper Quartile 600 ...... ':7492

21---+---+---f----1-+--~~--+~ 500 400 7465 300 '.7450

200 »»»>>>>> .. 7428 2t--+----+--+-+---+--+---+-t---+--+---+---I 100 7400

FMAM JJ A SON 0 J FMAM J J; A . S ;7186 Lower Quartile Projected 1983

21-----+---+---+-+---+--+---+-+---+--+---+--f

Legend Most Adverse Most Probable Upper Quartile Lower Quartile 2.---+--+---+-+---+--+---+-t---+--+---+---; Most Adverse 1 o N 0 J FMAM J s

11 Navajo Reservoir [San Juan River]

Water Year 1982 Water Year 1983 Navajo Active Storage* Chart 4 At the beginning of the water year, the On September 30,1982, Navajo Re-servoir Reservoir (Acre-Feet) reservoir elevation was 6052 feet with a stored 1,506,000 acre-feet of water at an EI. (Ft.) content of 1,246,000 acre-feet. It was elevation of 6072 feet. Assuming average gradually drawn down to 6048 feet prior to the inflow for water year 1983, the projected spring runoff. The water surface reached its elevation before snowmelt runoff begins is Maximum Storage 1,696,400 6085 highest elevation of 6072 feet by the end-of 6059 feet with a content of 1,329,000. By the Inactive Storage 660,500 5990 September 1982 with a content of 1,506,000 end of June 1983, the reservoir is expected to Surface Area (Full) 15,610 Acres acre-feet. reach an elevation of 6081 feet with a content Reservoir Length of 1,641,000 acre-feet. This approximate (Full) 33 Miles During the first part of water year 1982, 530 elevation will be maintained throughout the "'does not include 12,600 acre-feet of dead storage cfs was released for consumptive use and summer to enhance recreational use. below 5775 feet maintenance of fish and wildlife. The April-July 1982 inflow was 685,000 acre-feet, Releases from Navajo Reservoir for an upper which is 97 percent of the long-term average. quartile inflow are projected to average 1,200 Total inflow for the water year was 1,159,000 cfa through the fall and winter and increase to acre-feet, 115 percent of normal. During-the a maximum of 2,000 cfs during the summer. water year, a maximum i"nflow of 6,650 cfs For an average inflow, releases are expected occurred on May 4. to average about 1,250 cfs throughout the year. The projected lower quartile and most adverse releases are projected to average about 900 cfs and 700 cfs, respectively, throughout the water year.

12 Outflow Release in 1000 Cubic Feet/Second Storage Actual Operation 1982 Usable Content in 1000 Acre-Feet Elevation in Feet (Non-Linear Scale) 5 4....---+--+-4---+--4----f.-+--+----f.--+---+---1 3 21---+-~-f---+---I-----+-...... "",,,,,...f-----+-+---+----I 16961---+--4----+----11--+---+--I---+----1_+---+,--I--4----+_+---+--+--+---+_~ ;::--+--+-----f6085 1 IIl2JJLllijjti&tr&1ruuJthw&tMU&1IU 15001----+----+----+----+----+---+---+--+---+----+----+----+---+--+----+--+---I---+---+---+ 6072 Projected Operation 1983 Upper Quartile

41---+-~-1----+---I-----+-+--+-----+-+---+----I 31----+-~-1----+---I-----+-+--+-----+-----+---+----I 6029 2' I--~----+-+---+---+- 1

Average 5966

41----+---+---1-+--+---f--f---+---+----Io-+---4 3....---+--+-t---+--+----f.-+--+----f.--+---+---1 2t---+--+-----+-+--+--+-t---+--+----f.-+--f 5720 ONDJ FMAMJJ ASONDJ FMAMJJ AS 1 ...... ·.··········:.::··:···:··:.·:··::·:··:11.. ··:: .. '.··".:...... Actual 1982 Projected 1983 Lower Quartile Legend 3 Most Probable 2 Upper Quartile 1 ::::1:: Lower Quartile Most Adverse ••• "

Most Adverse

3~-+---+-~1----+---I-----+-+--+-----+-+---+----I 2~-+---+-~1----+---I---+-+--+-----+-+---+----I 1 ONDJ FMAMJ J A'S 13 Lake Powell [Colorado River]

Boating on Lake Powell. Spillways in operation at Glen Canyon Dam.

Water Year 1982 Water Year 1983 Lake Powell Active Storage* Chart 5 During water year 1982, Lake Powell, which is By the end of September 1982, the elevation of Reservoir (Acre-Feet) EI. impounded by Glen Canyon Dam, was Lake powell was 3687 feet with a content of (Ft.) operated as part of the Colorado River Storage 23,005,000 acre-feet. Under average runoff Project (CRSP) in accordance with governing conditions, the reservoir is expected to be Maximum Storage 25,002,000 3700 contracts and laws to provide river regulation, drawn down to about 3681 feet by the spring Rated Head 9,428,000 3570 optimum power production, recreation, and of 1983, and reach a maximum elevation of Minimum Power 4,126,000 3490 fish and wildlife enhancement. 3699 feet by the end of July. At this elevation, Surface Area (Full) 161,390 Acres the content is 24.9 million acre-feet, 100 Reservoir Length On September 30,1981, the Lake Powell percent of active capacity, and the surface (Full) 186 Miles water surface elevation was 3672 feet with an area is approximately 160,650 acres. Under active storage of 20,751 ,000 acre-feet. The most probable through upper quartile inflow Power Plant April-July 1982 runoff above Lake Powell was conditions, releases from Lake Powell are Number of Units 8 8,392,000 acre-feet, approximately 110 projected to range from 9.6 to 12.0 million Total Capacity 1,021,000 Kilowatts percent of the long-term average. The water acre-feet in order to equalize storage with *does not Include 1,998,000 acre-feet of dead surface elevation was drawn down to a Lake Mead by the end of September 1983. storage below 3370 feet minimum of 3662 feet by mid-February, and a Under lower quartile conditions, or less, the maximum level of 3687 feet was reached by scheduled releases are 8.23 million acre-feet. August 1982. This approximate level was maintained throughout the remainder of the water year. Total releases from Lake Powell amounted to 8,295,000 acre-feet.

14 The fishing Is good. Lake Powell. Inflow -- Outflow Storage Actual 1982 in 1000 Cubic Feet!Second Usable content in Million Acre-Feet Elevation in Feet (Non-Linear Scale) 50 1---4---1---+--I--+---1---+--I--+---1---+~ 251----+---+---+---+--+--+--+---+--+---+---+---+---+---+---+---l---l_t--+--+--+-=,..+----+---l 3700 40 1--...... --1---+--I--+---1---+--I=-+---1---+~ 30 1---I----+----f--+---I----+----+-JtIIIF-_+__ Ilr---I----+----I 20 1---4---1---+-_I--+---1--2lfIf-_1--- 10 ": 3667 Projected 1983 Upper Quartile 50' .....----.-----t---,F--,___---r---,~,_--r----r___. 40 1--4--4---+--I--+---1---+--#-I--Jlr--4---+---I 15 " 30' 1---1-----l1----I----Ii---I-----I---.IIL.-....fi---l-4r---t---t---t ""''''»»>>>''""3627 20 1--4--4---+--I--+-~It-f--...... 10 """ 10 :3577 Average

40 .I----I----f-----ll---I---I-__+-+---+---+-_I--_+__--I 30 I---I----I-__+--I---I-----+-----l~~...... __+-+--t 20 1---I----I-__+--I---I-----+-~F___+__-I-lIIlIIlirI:_I_ 3506 10

Lower Quartile " 3132 o 0 N "O""J FMAMJJA SON 0 JFMAMJ 'j""'» A S 30 1---I--~--+---+----lI---t---t--b~-+---t---1 Actual 1982 Projected 1983 20 1---I---4---I--I---I--__t_--+-#-I--~__t_--+---I 10

Most Adverse Legend 20 1---I---+----I----f.~I--+_-+--+--+-t__-r--; Most Probable 10 Upper Quartile Lower Quartile o N" 0 J FMAM J J AS Most Adverse ••• ••• ••••••

15 Lower Basin Reservoirs Lake Mead [Colorado River]

Water Year 1982 Water Year 1983 Lake Mead Active Storage* Chart 6 At the beginning of water year 1982, Lake During the 1983 water year, the Lake Mead Reservoir (Acre-Feet) Mead, impounded by Hoover Dam, had a water level is scheduled to rise to 1213 feet at EI. (Ft.) water surface elevation of 1193 feet and an the end of February 1983, then be drawn down active storage of 21 ,870,000 acre-feet. During to a low elevation of 1207 feet at the end of Maximum Storage 27,377,000 1229 the water year, releases were made to meet June 1983. At that level, the lake will have an Rated Head 13,653,000 1123 downstream water use requirements in the average active storage of about 23.9 million Minimum Power 10,024,000 1083 United States and Mexico, programmed levels acre-feet. During water year 1983, a total of Su'rface Area (Full) 162,700 Acres of Lakes Mohave and Havasu, and transit about 7.5 million acre-feet is scheduled to be Reservoir Length losses which include river and reservoir released from Lake Mead. (Full) 115 Miles evaporation, uses by phreatophytes, changes in bank storage, unmeasured inflows, and Power Plant diversions. Number of Units 17 Total Capacity 1,344,800 Kilowatts The total release from Lake Mead through *does not include 2,378,000 acre-feet of dead Hoover Dam during water year 1982 was an storage below 895 feet estimated 7,377,000 acre-feet. At the end of the water year, Lake Mead had a water surface elevation of 1199 feet and an active storage of 22,770,000 acre-feet which reflect an increase in storage during the water year of 900,000 acre-feet. On September 30,1982, the active storage of Lake Mead was 240,000 acre-feet less than the active storage in Lake Powell.

16 Unwaterlng penstocks at Hoover Dam.

Outflow Release in 1000 Cubic Feet/Second Storage Actual Operation 1982 Active Content in Million Acre-Feet Elevation in Feet (Non-Linear Scale) 201---+--+-+---+--+-+---+--+-+---+--+--1 151---+--+---l1---+--4-- 10 1----4----I--~-+- 5.-11I Projected Operation 1983 Upper Quartile

20 ....-+--+---+~+--+--+-....-+---f---+-~-I 15....---f----1----4-- 10 ~-I---I-- 5 15 1136 Average, Lower Quartile, Most Adverse

20 1---1----1--1---+----1--...-.--+----1--01---+---4----1 15 1----I----I--~--f--4- 10 101---+--+---lI---I--- 1083 5 o N 0 J FMAM JJ AS 5

895 o N 0 J F M A M J J A SON 0 J of MAM J JA Actual 1982 Projected 1983

. Legend Most Probable Upper Quartile

17 Lake Mohave [Colorado River]

Water skIIng on lake Mohave. Aquatic Impact studies.

Water Year 1982 Water Year 1983 Lake Mohave Active Storage* Chart 7 At the beginning of water year 1982, the water The water level of Lake Mohave is scheduled surface elevation of Lake Mohave, which is to rise through the fall and winter months and Reservoir (Acre-Feet) EI. impounded by Davis Dam, was 635 feet, with reach an elevation of 644 feet by the end of (Ft.) an active storage of 1,475,000 acre-feet. May 1983. Because of heavy irrigation use during the summer months, the water level in Maximum Storage 1,810,000 647.0 Rated Head 1,188,000 623.0 During the winter and spring months, the Lake Mohave is expected to be drawn down to an elevation of 630.5 feet by the end of water Minimum Power 217,500 570.0 water level was gradually raised to 647 feet, Surface Area (Full) 28,200 Acres year 1983. During that time a total of 7.8 with an active storage of 1,806,000 acre-feet Reservoir Length million acre-feet is scheduled to be released near the end of May 1982. The water level (Full) 67 Miles was drawn down during the summer and the from Lake Mohave to meet all downstream reservoir ended the water year at elevation requirements. Power Plant 633 feet with 1,426,000 acre-feet in active Number of Units 5 storage. Total Capacity 240,000 Kilowatts

... does not include 8,530 acre-feet of dead storage Lake Mohave releases were made to satisfy below 533.39 feet downstream requirements, with a small amount of reregulation at Lake Havasu. During the water year, approximately 7,515,000 acre-feet were released at Davis Dam, all of which passed through the turbines for power production.

18 Scenic Davis Dam. Infrared thermometer determines water needs.

Lake Mohave Outflow Lake Mohave Storage Actual Operation 1982 Usable Content in Million Acre-Feet Elevation in Feet (Non-Linear Scale)

201---+---+-----11--_+_--+-.f--_+_-+-f---+--+----I 151---+---+-----11--_+_--+----1 1.8 t---+---+--+--+---+--+----Ir---+----+---+--+--+---+---+----Ir---+----I---+--+--+---+--+--I---;647 1 01---+---+-----11---+-~ S... -+---+-----1636 Projected Operation 1983 Upper Quartile 20 t---+---+-_t---+---+--+---+---+--+----I---4~ 615 15t----+---+- 101---+----+---,.,i 5'

Average, Lower Quartile, Most Adverse 201---+---+--1--_+_--+-+--_+_--+-+---+--+----f 15t---+---+---f--+----+---"Il'f~d__--f---...... +.~ 10 t----+----+---+-+___o o 0 N: 0 JFMAMJ J A SON 0 J FMAMJJA S' Actual 1982 Projected 1983 ONDJ FMAMJ JAS

19 Lake Havasu [Colorado River]

Urbanization contrasts with desert and agricultural land.

Water Year 1982 Water Year 1983 Lake Havasu Active Storage* Chart ! At the beginning of water year 1982, the water Lake Havasu is scheduled at the highest levels level of Lake Havasu, impounded by Parker consistent with the requirements for Reservoir (Acre-Feet) Et(Ft. Dam, was at elevation 447 feet with an active maintaining reservoir regulation space. The Maximum Storage 619,400 450.0 storage of approximately 569,000 acre-feet. yearly low elevation of approximately 446 feet Rated Head 619,400 450.0 The reservoir was drawn down to is scheduled for the November through Minimum Power 439,400 440.0 approximately elevation 445 feet, with an February high flood hazard period. The Surface Area (Full) 20,400 Acres active storage of about 530,000 acre-feet in yearly high of about 450 feet is scheduled for Reservoir Length March to provide vacant space for runoff from the low flood hazard months of May and June. (Full) 35 Miles the drainage area between Davis and Parker During water year 1983, a total of Dams. The water level was then ra!sed to an approximately 6.8 million acre-feet is Power Plant approximate elevation of 450 feet by the end scheduled to be released from Lake Havasu to Number of Units 4 of May, with an active storage of about meet all downstream requirements. Total Capacity 120,000 Kilowatts 622,000 acre-feet. By the end of the water *does not include 28,600 acre-feet of dead storage year, Lake Havasu was drawn down to about below 400.0 feet 447 feet with an active storage of 560,000 acre-feet.

During the water year, approximately 6,371 ,000 acre-feet were released at Parker Dam, all of which passed through the turbines for power production. That amount included" flood control releases from Alamo Dam on the Bill Williams River.

Space in the top 10 feet of Lake Havasu (about 180,000 acre-feet) is reserved by the United States for control of floods and other uses, including river regulation. Normally, only about the top 4 feet, or 77,000 acre-feet of space, have been used for this purpose since Alamo Reservoir on the Bill Williams River has been in operation.

20 Outflow Release in 1000 Cubic Feet/Seco·nd Storage Actual Operation 1982 Usable Content in 1000 Acre-Feet Elevation in Feet (Non-Linear Scale) 450 15r---+--+---+-+---+---t--"--t-t---t---t---t----l t=t=tJct=t=tjJjJ.il;::trrrt=t=t=t:dI.R~liJ=J=J 1Ol---+---+--+---+-- 600 449 5•... _iii. 500: 444 Projected Operation 1983 Upper Quartile 400

151---+---+- 101---+---+---, 300 431

5 11:.... 200 Average, Lower Quartile, 424 Most Adverse 100 415 15r---+--+---+-+---+---t--"--t-t---+--+---+----I 10 J---+---+----+----4-h#+4+ff~P+df:+ 400 5...__ o N 0 J FMAM JJ A SON 0 J FMA .M JJ AS o N0JFMAMJJAS Actual 1982 Projected 1983

21 River Regulation

iiii¥.. Releases from Bartlett Dam. Gila River flooding.

The natural virgin runoff reaching the streams The projected release from Lake Powell, Adjustments to the normal releases are made of the Colorado River drainage system above based on lower quartile runoff conditions or when conditions permit to provide more Glen Canyon Dam during water year 1982 was less, is 8,230,000 acre-feet. The projected satisfactory conditions for water-oriented estimated at about 16.3 million acre-feet. Of release for an upper quartile runoff condition recreation activities, to provide transport for this amount, about 3.9 million acre-feet were is 12,000,000 acre-feet. When added to the riverborne sediment to desilting facilities, and consumptively used within the Upper flow of the Paria River, this would result in an to assist in controlling water quality. Releases Colorado River Basin States. Upper Basin delivery ranging from 86.8 to from Lake Powell were at least 1,000 cfs 90.5 million acre-feet for the 10-year period during the winter months and were increased Adjustments in storage in mainstem ending September 30,1983. to at least 3,000 cfs during the summer reservoirs resulted in an inflow to Lake Powell months. Minimum daytime releases during of 11.1 million acre-feet. The release from Daily releases are made from the storage the summer months averaged 8,000 cfs. Glen Canyon Dam, based on measurements at reservoirs in the Lower Basin to meet the the gaging station at Lees Ferry, Arizona, was incoming orders of the water agencies. River regulation below Hoover Dam resulted 8,295,000 acre-feet. For the 1-year and Normally, all water passes through the in a total delivery to Mexico of approximately 10-year periods ending September 30,1982, powerplant units. The daily releases are 330,000 acre-feet in excess of the treaty 8,312,000 acre-feet and 89,679,000 acre-feet, regulated on an hourly basis to meet as nearly quantity (1 ,500,000 acre-feet) during water respectively, passed the Compact point at Lee as possible the power loads of the electric year 1982. Of that amount, 145,000 acre-feet Ferry. power customers. Minimum daily flow of drainage waters were bypassed for sal inity objectives are provided in the river to control pursuant to provisions of Minute No. maintain fishery habitat. 242 of the Commission.

22 Flood Control

Lake Mead is the only reservoir on the Local flood control protection was provided by Colorado River in which a specific space is the reservoirs within the basin during water exclusively allocated for mainstem flood year 1982, wh ich received greater total control. Flood control regulations for Hoover precipitation than during normal years. Total Dam are being updated and revised based on Colorado River reservoir system storage at the findings of a joint study by the Bureau of start of water year 1982 was approximately Reclamation (Reclamation) and the Army 49.6 million acre-feet and about 54.0 million Corps of Engineers (Corps) with consultation acre-feet at the end of the water year, and advice of State and local interests. representing a 4.4 million acre-feet decrease in total remaining available reservoir space. A final report which summarizes the study findings and recommends a new flood control In addition to the mainstem structures, Alamo operation plan for Hoover Dam is scheduled Dam on the Bill Williams River, and Painted for release in 1983. Subsequent to approval of Rock Dam on the Gila River (both in the Lower the report, the new flood control regulations Basin) received flood inflow during winter for Hoover Dam will be formally promulgated. months. Painted Rock and Alamo Reservoirs Flood control storage space will be maintained are scheduled to be operated at minimum in Lake Mead as stipulated in the Field flood control levels during 1983. Working Agreement between Reclamation and the Corps for flood control operation of Hoover Dam and Lake Mead. These stipulated regulations establish releases in a manner that maximizes public benefits in the United States with reasonable consideration for conditions in Mexico.

23 Beneficial Consumptive Uses

Concrete cross-drainage pipe. Water quality analysis.

Upper Basin Uses and Losses The major water diversion above Parker Dam For water year 1983, a release of 7.5 million The three largest sources of consumptive use was by The Metropolitan Water District acre-feet from Lake Havasu has been in the Upper Colorado Basin are agricultural (MWD) of Southern California. MWD projected, including consumptive use use within the drainage basin, diversion to pumped approximately 770,000 acre-feet from requirements in the United States below adjacent drainage systems, and evaporation Lake Havasu during water year 1982. None of Parker Dam, transit losses in the river losses. During water year 1982, the estimated this water was utilized for delivery to the city . between Parker Dam and the Mexican Border, use for agricultural and municipal and of Tijuana, although the contract for and treaty deliveries to Mexico. industrial supply in the Upper Basin was temporary emergency delivery of a portion of 2,460,000 acre-feet. Estimated evaporation Mexico's treaty entitlement is still in During water year 1983, MWD is expected to losses were 681 ,000 acre-feet from mainstem existence. During water year 1982, releases divert 733,000 acre-feet by pumping from reservoirs. Approximately 783,000 acre-feet of approximately 7,515,000 acre-feet were Lake Havasu. Consumptive uses by small were diverted for use in adjacent drainage made from Lake Mohave to provide for users, river losses or gains, and reservoir basins. Thus, total estimated consumptive releases at Parker Dam; to supply diversion losses between Davis Dam and Parker Dam use amounted to 3,924,000 acre-feet. Storage requirements of MWD, miscellaneous are projected to be a net loss of 219,000 in the Upper Basin mainstem reservoirs contractors, and other users; to offset acre-feet. increased by approximately 3.6 million evaporation and other transit losses between acre-feet during water year 1982. Davis and Parker dams; and to maintain the There are no major users between Hoover scheduled levels of Lake Havasu. Dam and Davis Dam. During water year 1983~ lower Basin Uses and losses consumptive uses by small users, river losses During water year 1982, an estimated During water year 1982, releases of or gains, and reservoir losses between Hoover 6,371 ,000 acre-feet of watee were released approximately 7,377,000 acre-feet were made Dam and Davis Dam are projected to be a net from Lake Havasu to meet the requirements from Lake Mead at Hoover: Dam to regulate gain of 202,000 acre-feet. The net diversions for water deliveries at Imperial Dam, as well the levels of Lake Mohave and to provide for from Lake Mead are projected at 143,000 as those of the Colorado River Indian the small users and the losses from this acre-feet. Evaporation frorn Lake Mead is Reservation near Parker, Arizona, the Palo reservoir. In addition, 138,000 acre-feet were expected to be about 993,000 acre-feet and ne1 Verde Irrigation District near Blythe, diverted from Lake Mead for use by Lake gain between Glen Canyon Dam and Lake California, other miscellaneous users along Mead National Recreation Area, Boulder City, Mead is expected to be about 881 ,000 the river, and transit losses between Parker Basic Management, Inc., and contractors of acre-feet. Dam and Imperial Dam. the Division of Colorado River Resources, in Nevada. During water year 1982, the total releases and diversions from Mead estimated 7,515,000 acre-feet. Water Quality Operations

Since water quality aspects of Colorado River No large amount of Gila River infiltration to "" operations are extensively described in the the Wellton-Mohawk Irrigation and Drainage biennial series of reports entitled Quality of District is expected during water year 1983 Water, Colorado River Basin, only minimal because no flood control releases from Painted discussion of this aspect of operation is Rock Reservoir are anticipated to reach the presented in this report. Report No.11 of the Colorado River. The total flows in the Bypass biennial series was issued in December 1982. Drain during water year 1983 are estimated to be about 150,000 acre-feet. No bypass waters During water year 1982, the United States are expected to be returned to the Colorado bypassed a total of 145,000 acre-feet through River below Morelos Dam during water year the Bypass Drain. This water was replaced 1983. with a like amount of other water, pursuant to Minute No. 242 of the International Boundary In recognizing the need to manage water and Water Commission. quality of the Colorado River, it has been recommended that long-term salinity Under the provisions of Minute No. 242, the increases in the river be controlled through a Republic of Mexico is entitled to receive at water quality improvement program generally Morelos Dam water of a quality no worse than described in the report, Colorado River Water 115 parts per million (pI m) (.±. 30 pi m) Quality Improvement Program, dated dreater than that arriving at Imperial Dam. February 1972, and a status report of the same During water year 1982, the average salinity title, dated January 1974. )f the Colorado River at Imperial Dam was 823 )/m. During that period the average salinity The program calls for a basin-wide approach )f the waters at Morelos Dam was 938 p/m, to salinity control while the Upper Basin "esulting in a salinity differential of 115 p/m, continues to develop its compact-apportioned within the provision of Minute No. 242. waters. The initial step towards improvement of the quality of the river's water was authorization by the Congress of the Colorado River Basin Salinity Control Project (Public Law 93-320), on June 24,1974.

25 Environmental Programs

Artist's concept of Yuma Desalting Plant. Ali-American Canal desUting basins.

Upper Basin In water year 1983, Reclamation, in maintenance and operation of the Dam is Although excellent trout tailwater fisheries cooperation with the National Park Service being negotiated with the Arizona and Nevada were created through the construction and (NPS) and other non-Federal agencies, will SHPO's and the Council. As provided for in operation of the Upper Basin dams and initiate studies in the Grand Canyon. The Council regulations, the agreement will allow reservoirs, the cold, clear water also changed purpose of these studies is to better quantify for a one time consultation to cover ongoing habitat for several rare native fish in the the impacts of the current operation of Glen operation and maintenance at the Dam. The Green, Colorado, and San Juan Rivers. In Canyon Powerplant. They will concentrate on agreement will make it possible for order to evaluate the impacts of reservoir sedimentation and the biology of the Colorado Reclam'ation to fulfill both the' 'spirit and the operation on the native fish, a Colorado River River and its shoreline in the Grand Canyon; letter of the law" in preserving the sianifilcar,t Fishery Project was initiated. Over the last 3 analyze the effects of the current operation of historic qualities of Hoover Dam. years, many State and Federal wildlife Glen Canyon Powerplant; and address various resource agencies, along with Reclamation, alternatives to the present operations. The Central Arizona (CAP) will be one participated in the joint study effort. of the largest and most com plex projects that Lower Basin Reclamation has ever constructed. The In April 1982, a three-vo~ume final report was Hoover Dam is internationally recognized for cultural resources, both historical and cooperatively prepared and released by its engineering and architectural design as archeological, affected by the project are Reclamation and the Fish and Wildlife Service well as its far reaching social and economic correspondingly rich and complex. The nearl) (FWS). Findings of the study included the impacts. Therefore, it is listed on the National 400 miles of aqueduct that will transport abundance and distribution of endangered Register of Historic Places. Regulations of the Colorado River water to users in central Colorado squawfish, humpback chub, and Advisory Council on Historic Preservation Arizona, and the associated storage and bonytail chub in the Upper Basin. Monitoring (Council) require that Federal agencies regulatory features, will affect hundreds of of fish movements, reproduction, and consult with both the appropriate State archeological and historical sites. population stability was also conducted .. Historic Preservation Officer (SHPO) and the Reclamation already has an extensive survey Recommendations on appropriate flows to Council itself when a National Register and mitigation program in progress to fulfill help pres,erve the fish in their natural habitat property may be affected by an agency action. its responsibilities for the preservation and were also made. management of these cultural resources. Because of this, under normal circumstances Additional monitoring will continue on the the Arizona and Nevada SHPO's would be In order to unify the cultural resource progran rare fish to insure continued compatibility consulted for even routine maintenance and for the entire CAP, Reclamation's between the exotic and native fish in the operation of Hoover Dam. In order to Preservation Officer is preparing a Cultural Upper Colorado River system and future eliminate the repetitive and time consuming Resource overview. The overview will development and use of the water resources of process of consulting with the SHPO's, a summarize the results of the work already the Upper Basin States. Programatic Memorandum of Agreement for accomplished. Because the location for many

26 Recreation below Davis Dam. Humpback Chub.

of the CAP facilities corresponds closely with Information gathered on deer use of a canal Deer mortality in the Coachella Canal was the territory of the HoHoKam culture, the with a record of mortalities and success of lower during the 1982 dry season (late resu Its of CAP-related archeological research various escape devices will be useful in summer). is adding much to the knowledge of these planning mitigation for the CAP and other ancient farming people. The HoHoKam area canal systems. Work is nearing completion on an centered in the drainages of the Lower Gila, "Environmental Data System (EDS)" for the and the Salt and Verde Rivers in the Phoenix The Lower Colorado Region is also Lower Colorado River. EDS is a means of Tucson region. The overview will not only cooperating in a multiagency effort to study cataloging environmental data using a river summarize much of our present knowledge of the nesting population of bald eagles in mile location procedure on Reclamation's the area, but will also develop an overall central Arizona. The population of this Cyber computer. Modules currently in use research strategy for the project. This will endangered species may be affected by are vegetation community types and insure a better integrated approach to certain regulatory storage features of the structures, wildlife (bird) species densities, fulfilling Reclamation's responsibilities, will CAP. Objectives of this study include the and recreation. After a 1- to 2-year test help eliminate duplication of effort between summarization of existing data and period, a decision will be made whether or not project features, and will produce a more construction of a model to evaluate to implement several other aquatic modules effective program in terms of research and reproductive success, the determination of designed to be a part of an EDS. preservation. annual productivity and population trends, the determination of abundance and distribution Reclamation has recently initiated a 2-year fhe overview is also making it possible to of fish serving as prey for the eagles, the aquatic study in the Yuma Division (Laguna :ievelop a Programatic Memorandum of evaluation of the effects of human Dam to Morelos Dam) of the Colorado River. t\greement with the Council and the Arizona disturbance, the identification of prey, and the The purpose of this study is to gather baseline ind New Mexico Historic Preservation determination of movements of nesting adults data on selected physical and biological )fficers. The agreement will satisfy cultural via radio telemetry. parameters which can be used to describe 'esource consultation requirements with the existing conditions in this reach of river. The ~ouncil for the entire CAP. A cooperative study with the California information will be used in project planning, Department of Fish and Game is currently impact assessment, and as a base for Jnder a Memorandum of Agreement with the underway to evaluate the effectiveness of post-project comparisons associated with the :WS, desert wildlife populations along CAP windmill watering devices recently placed Yuma Division Flood Control Project. The :anal alinements are being studied. These along the Coachella Canal. Providing water to control study is being completed by Arizona ;tudies, concentrating on the impacts of desert mule deer at a site away from the canal State University fishery biologists. :anals on desert ungulates, are being may reduce a significant mortality problem. ;onducted by the University of Arizona's Preliminary indications are that the windmill ~ooperative Wildlife Research Unit. drinkers are used by deer and other wildlife.

27 Power Operations

Lake Powell and Glen Canyon Dam. Blue Mesa Powerplant.

Upper Basin-Colorado River Storage Project will allow Reclamation to determine how best Purchases [for] Kilowatt-houri During water year 1982, a significant effort to use the additional capacity. Parker Davis Firming was made to complete National Rio Grande Firming °o Environmental Policy Act compliance for the The final Environmental Assessment on the CRSP Firming 1,054,899,302 proposed uprating of generators at Glen Glen Canyon Powerplant uprating is Fuel Replacement 871 ,992,698 Canyon Powerplant. The proposed uprating scheduled to be issued by December 1982; a Subtotal Purchases 1,926,892,000 of each of the eight generators from a decision as to whether to proceed with the maximum capacity of 143.75 megawatts (MW) uprating is expected to follow shortly to a maximum capacity of approximately thereafter. Miscellaneous 167.00 MW involves replacing or reinsulating Transmission for others 243,451 ,000 field windings, strengthening rotor arms, and The following table summarizes the CRSP Exchange 27,692,000 making minor mechanical modifications such generation, purchases, disposition, and Power Del iveries from as changing the fan assembly to increase revenues from power operations for fiscal year Others (I nterchange) 792,000,000 airflow cooling. 1982 and presents projections for fiscal year 1983. Total Energy Receipts 7,975,467,100 In January 1982, a Draft Environmental Assessment for Glen Canyon Powerplant The total revenue from power operations in Uprating was circulated for public comment. fiscal year 1982 was $81 ,263,038. For fiscal Disposition of Energy Due to adverse response to this document, year 1983, estimated revenues are Firm Energy Sales 5,597,152,591 primarily from environmental groups and the $85,000,000. Nonfirm Energy Sales 871,992,698 river recreation community, Reclamation Power Delivered to Others sponsored a river trip in the Grand Canyon (I nterchange) 549,000,000 during the period of May 24-27,1982, to allow Water Year 1982 System Losses 957 ,321 ,811 those people involved in, or those people who Total Energy Distributed' 7,975,467,100 could be affected by, an uprating decision to Sources of Energy observe firsthand some of the potential Net Generation Kilowatt-hours problems which were identified by those Flaming Gorge 433,017,000 Revenue commenting on the Draft Environmental Blue Mesa 184,471,000 Firm Energy Sales $49,416,326.82 Assessment. It was concluded that Morrow Point 261,986,000 Nonfirm Energy Sales Reclamation should initiate a cooperative Fontenelle 62,550,500 (Oil Conservation) study with the NPS to determine the impact of Glen Canyon 3,881,478,000 Parker Davis Firming the present operation of Glen Canyon Crystal 161,929,600 Wheeling for Others Powerplant on the Grand Canyon and to Subtotal-Net Generation 4,985,432,1 00 Miscellaneous Income further assess various alternatives to the Total Revenue present operation. The results of this study 28 Turbine runner enroute to powerplant.

GenerafIng Unl-I M-sintenance GC -1 GC-2 .- GO-3 ... GC-4 !lIIIIIII 40,000 GC-5 81,500 GC-6 GO-? .. :stimated Revenue $85,000,000 GC-B .- - ....- F.G. - 1 .. F.G. - 2 .. F.G. - 3 B.M. -1 - 11II. •• B.M. - 2 •• M.P. -1 ..- -- M.P. - 2 ... Crystal ... Fontana _ Oct. :Nov. Dec. Jan. Feb. : Mar. Apr. May June JUly Aug. Sep. G.C. -1 .. GaC. - 2 G.C. - 3 '- - G.C. - 4 .- - G.C. - 5 .. G.C. - 6 G.C. -7 .. G.C.. - 8 .. F,G - 1 -II FG - 2 .- F,G - 3 ..- 8.M - 1 - 8.M ,- 2 ~ M.P. -1 I- .. ... - M.P. - 2 - Crvstal - Fontanelle - -- -- 29 Power Operations [Cont.]

Hoover Dam and Powerplant. Davis Dam control room.

Lower Basin· Water Year 1982 Water Year 1983 The lower Nevada penstock is scheduled for The total energy delivery to the Hoover In operation studies of Lake Mead and Lake reconditioning during water year 1983. Also allottees during the 1982 operating year Powell for the Hoover operating year, which scheduled this year is the uprating of (June 1,1981 - May 31,1982) was ends May 31 , 1983, the amounts released at Generating Unit N-7 and the replacement of 3,562,610,052 kWh. There was no secondary Hoover Dam have been projected to satisfy turbine runners in Units A-6 and N-5. or disputed energy delivered to the Hoover only minimum downstream water allottees during the operating year. requirements, including diversions by MWD, Unit 2 at Davis Dam damaged its lower guide while complying with the overall requirements bearing twice last year. A major overhaul of The remote control operation of Davis and to meet compact and operating criteria release the thrust bearing support was conducted Parker Powerplants began during water year provisions. The water scheduled to be along with realinement of the unit. This unit 1982. These generator units are now released will generate about 83.2 percent of was scheduled to go back on line the first pari com puter operated from the Department of defined firm energy. The estimated monthly of this water year. Energy's Phoenix Dispatch Office, using Hoover releases during the operating year hourly gate opening and megawatt schedules total 7.5 million acre-feet. It is estimated that The following charts illustrate Lower Basin input and modified by Reclamation's Water generation from these Hoover releases, along generator unit outage schedules for water Scheduling Branch in Boulder City, Nevada. with the Hoover to Parker-Davis interchange, year 1982 and water year 1983. will result in delivery to the allottees of about All scheduled periodic maintenance at 3.3 billion kWh of electrical energy. Hoover, Parker, and Davis Powerplants was performed in water year 1982. Hoover's four water intake towers were inspected with an underwater television camera borrowed from Grand Coulee. The inspection showed that the structural integrity of the intake towers is sound. The uprating of Generating Unit A-5 was completed and Unit N-8 was rewound.

30 Generating Unit Maintenance

Oct. Noy. Dec. Jan. Feb. Mar. Apr. ' May June July Aug. Sep. Oct. Noy. Dec. Jan. Feb. Mar. Apr. j May June July Aug. Sep.

A-1 III1IIiII A-1 A-2 .. A-2

A-3 lIiIIIlIII A-3 IlIIIBIII A-4 - A-4 - A-5 A-5 iB&

A-6 III1IIiII A-6

IillIIIIIIlI -- A-7 A-7 IIIIIil

A~8 IIlilIIIlIIIt A-8

IIIIIJ - A-9 A-9 N-t .' N-1 IIIIIIlllIlI!iI ~ I\lIlIllIIIIIII -IIll\lIIl N-2 - N-2 N-3 IIIlIIl N-3 - !IIIiilIIIllIII ~ - N-4 N-4 N-5 . - N-5 -lIII'Im .-... N-6 ' II!1IIIl!Il1IJI ~ N-6 N-7 • N-7 - N-B , N-8 ml\!I D-1 ~ 0-1 UlllillilD

i ! , ~ + I ! I ~ I f D-4 l ~ ~ lIlII!lIliIlJlI I f I I ~ ~ I i I i I ~ ~: ! ~ ~ I ~ - I i f f illl3W;'> ! I I ~ I I i j j F~ ~! ~ ~ ! I ~ ! f I ; I i I ~ ! § j i ! r I f + 1 f '* U.S. GOVERNMENT PRINTING OFFICE: 1983-683-079/50 As the Nation's principal conservation agency, the Department of the Interior has responsibility for most of our na tionally owned public lands and natural resources. This includes fostering the wisest use of our land and water resources, protecting our fish and wildlife, preserving the environmental and cultural values of our national parks and historical places, and provid.ing for the enjoyment of life through outdoor recrea tion. The Department assesses our energy and mineral resources, and works to assure that their development is in the best interests of all our people. The Department also has a major responsibil ity for American Indian reservation com munities and for people who live in Island Territories under U.S. administration.