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<br />iGG\ <br /> <br />Recovery from the 1977 Dry Year <br /> <br />The Board's 1977 Annual Report <br />noted that the virgin flow of the Colo- <br />rado River at Lee Ferry for water year <br />1976-77 set a new record for histori- <br />cal low flows and created severe de- <br />mands on Colorado River system <br />water supplies. The above average <br />runoff during the 1977-78 water year <br />increased Basin reservoir storage by <br />about 2.6 million acre-feet. Prelimi- <br />nary estimates of 1978-79 runoff, <br />based upon Upper Colorado River Ba- <br />sin snowpack conditions as of January <br />1, 1979, point to another year of <br />above-average runoff, This, combined <br />with unusually high streamflows dur- <br />ing December 1978 on the Bill Wil- <br />liams and Gila Rivers in the Lower <br />Basin, indicate a full recovery from <br />the effects of the 1977 dry year. <br /> <br />Potential Future Surplus Flows <br /> <br />The Board's 1977 Annual Report <br />described joint Bureau of Reclama- <br />tion-Corps of Engineers studies of al- <br />ternative reservoir operating strategies <br />during the years prior to completion <br />of the Central Arizona Project when <br />surplus flows are imminent and reser- <br />voir spills are likely to occur. These <br />studies continued during 1978 but, <br />due to a lack of urgency resulting <br />from the drawdown of about 5.6 mil- <br />lion acre-feet of water from storage in <br />1977, no meetings were held on their <br />findings. <br /> <br />Program for Banking Water <br />in Lake Mead <br /> <br />During 1978, meetings were held <br />between the California State Depart- <br />ment of Water Resources, The Metro- <br />politan Water District of Southern <br />California, and the Board to discuss a <br />concept for banking, or storing, water <br />in Lake Mead. Briefly, the concept in- <br />volves Metropolitan increasing its <br />deliveries from the State during years <br />of good supply for the State Water <br />Project, taking less than its annual <br />Colorado River apportionment, and <br /> <br />having a like amount credited to its <br />account in Lake Mead, In years of <br />low water supply from the State Wa- <br />ter Project, in addition to its annual <br />apportionment, Metropolitan would <br />divert water credited to its account in <br />Lake Mead, <br />The proposal was also discussed <br />with representatives of the other Cali- <br />fornia Colorado River water contrac- <br />tors and the States of Nevada and <br />Arizona and it was agreed to com- <br />mence studies on this concept. <br /> <br />Water Quality <br /> <br />Colorado River Salinity Standa;ds <br /> <br />The Colorado River Basin states in <br />1975 adopted numerical standards for <br />salinity in the Colorado River. Under <br />the provisions of Section 303 (c) ( 1) of <br />Public Law 92-500, the states are to <br />review these standards at least once <br />during each three-year period and, as <br />appropriate, to modify them. <br />The seven-state Colorado River Ba- <br />sin Salinity Control Forum, through its <br />permanent Work Group, which is <br />chaired by the Board's Chief Engineer, <br />conducted engineering studies of fac- <br />tors affecting future salinity in the Col- <br />orado River and prepared a draft of <br />the report entitled "1978 Revision, <br />Water Quality Standards for Salinity <br />Including Numeric Criteria and Plan of <br />Implementation for Salinity Control, <br />Colorado River System", The report <br />constitutes the first triennial revision of <br />the standards and plan of implementa- <br />tion. <br />Following approval of the report by <br />the Forum on August 29, two regional <br />public hearings were held on Novem- <br />ber 14 and 16, in Las Vegas, Nevada, <br />and Grand Junction, Colorado. A sup- <br />plement to the report was then pre- <br />pared containing a summary and anal- <br />ysis of the comments received during <br />and after the meeting and appropriate <br />modifications to the report. On De- <br />cember 18, the Forum approved the <br />supplement and directed that the re- <br />port and supplement be sent to the <br />individual states for adoption. <br />The Forum found no reason to rec- <br />ommend changes in the numeric sa- <br /> <br />8 <br /> <br />linity criteria adopted in 1975 at the <br />lower mainstem stations, which are: <br /> <br />Salinity in mgj I <br />Below Hoover Dam....,.....,...., 723 <br />Below Parker Dam.,.......,..,...., 747 <br />Imperial Dam ..,....,..,............... 879 <br /> <br />Salinities at each of the stations <br />have been decreasing almost consist- <br />ently since 1972, In 1978, the flow- <br />weighted salinity at Imperial Dam, for <br />example, was 67 mgll below the nu- <br />meric criteria. The current and pro- <br />jected rate of basin-wide water <br />development is slower than estimated <br />in the 1975 report. Although progress <br />on the salinity control program also <br />has been slower than anticipated, <br />there is no reason to believe that the <br />numeric criteria will be exceeded dur- <br />ing the next three-year revision peri- <br />od. <br /> <br />Colorado River Basin Salinity <br />Control Program <br /> <br />The Bureau of Reclamation con- <br />tinued its efforts on Colorado River <br />salinity control projects and the Colo- <br />rado River Water Quality Improve- <br />ment Program in accordance with the <br />Colorado River Basin Salinity Control <br />Act of 1974, P.L. 93-320. The Soil <br />Conservation Service continued its ac- <br />tive role in salinity control through its <br />on-farm water management program. <br />A draft contract for the operation <br />and maintenance of the Grand Valley <br />Unit by local agencies was completed <br />by the Bureau. Execution of the con- <br />tract, which includes economic penal- <br />ties for excessive water diversions, is <br />required before construction can be- <br />gin on this unit. The Soil Conservation <br />Service continued its activities in the <br />Valley and issued its final report de- <br />scribing its proposed on-farm program <br />for salinity control. Current plans call <br />for completion of the salinity control <br />programs of the Bureau of Reclama- <br />tion and Soil Conservation Service in <br />1990 and an estimated reduction of <br />the salts picked up in the Grand Val- <br />ley by 410,000 tons annually. <br />The Bureau completed the Environ- <br />mental Impact Statement and the <br />Definite Pian Report for the Paradox <br />Valley Unit. Construction of a tempo- <br />rary brine conveyance pipeline and <br />