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i ii The 1950s was a difficult decade for water users. Flood control measures were complicated and . costly; groundwater pumpmg began to i deplete surface flows. .\ capacity is removed as availa~Je "project :~ storage" and is reserved solely for flood control. Ji:iI ; PROJECT REl.EASES i:1t was anticipated by the drafters of the ;' compact that annual releases of 790,000 af (fTOrn project storage: would be needed to !~atisfy: New. Mexican, Texan~ and Mexican_"l ; water needs b,etween Elephant Butte arid _~_ f'OrtQuitman, Texas.In recent years, _ ' :j 1\oweyer, the a~nuaJ demand for project\:} [water has been'" slightly less than,700,OOO . ; at, j UNOERDELlVERIESBY NEW MEXICO fNew Mexico has difficulties achieving its i ctelivery obligations to Elephant Buttt? under-certain climatic conditions. This ; OCCUi's most commonly In years ofabun., ~_ dantshowfaU and spring runoff which \: fldwspast the inflow index gage at Otowi. ; Ifsuch conditions are followed by a lack ,: of summer thunderstorms, which create ,~ most Of the inflow be!c)w Otowi~ New f Mex.i~o will likely underdeliver. THE 1985 SPILL. ~ ;~ Althpugh no water actually flowed over , tl:teElephant B':ltte spillway, an #actual spillof usable water from project storage" occurred on June 13, 1985. This significant ",eyent cancelled t~e accrued debits of both ;- New Mexico and Colo~ado,Jn order to ..prev~nt flooding in th~ town of Truth or t Consequences, the compact states had agreed to store spring flood waters in upstream reservoirs rather than at Ele- ; phant Butte. Absent this storage,~a physi. : caI spill wou,ld have ocCurred at Elephant Butte; therefore, an "actual spill" as defined in thecompact resulted on paper. ~This paper spill was not the same as a ; "hypothetic~.J spill" as defined (somewhat ,,~,mbiguously) in Article I of the compact. I Such ,8 hypothetical spill has never ; occurred, nor is it expected to be applied. i Ahypothetical spill could only follow ~. years in which more than 790,000 af were ,released from project'storage. '- 14 001111 lowed developments in the 1950s which have continuing influence on river management. CHALLENGES OF THE 1950s , In many ways, the 1950s was a diffi, cult decade for water users in the New Mexico portion of the Rio Grande basin north of Elephant Butte. Flood control measures were complicated and costly; ground water pumping began to deplete surface flows; and provisions of the Rio Grande Compact proved difficult to meet. In 1951, Texas sued New Mexico and the MRGCD for noncompliance with the Rio Grande Compact of 1938. Under the compact, New Mexico is obligated to deliver to Elephant Butte 62% of the inflow to the middle reach of the Rio Grande as measured at Otowi bridge during a normal year. (Annual flow at Otowi averages nearly one million acre feet.) This percentage obligation falls slightly during dry years, and rises to greater than 75% during years of high runoff. The compact allows New Mexico to underdeliver up to a cumulative total of 200,000 acre feel. In 1951, records indicated that New Mexico, over the past decade, had underdelivered its compact obliga- tions to Elephant Butte by over 300,000 at, Texas sued to have the debt repaid and to require New Mexico to regulate diversions from the middle valley in order to ensure future com- pliance. Although the suit was thrown out of Court on a legal techni- cality (Le, the United States, which was not part of the suit, was found to be an indispensible party), New Mex- ico looked at ways in which it could better meet its delivery requirements. One way was to remove impediments to flow down the riverbed, as was being pursued by the Bureau of Reclamation in its channel rectifica- tion program. The Bureau also con- structed a 2,000 cfs conveyance chan- nel from San Acacia to Elephant Butte Reservoir in order to prevent loss of the Rio Grande flow to seepage and evaporation from the aggraded river- bed in this 70- mile stretch, Another means of promoting the delivery of water downstream was to prevent the drilling of new wells that robbed the Rio Grande of surface flows. The New Mexico State Engineer took this step in 1956 and restricted new ground water use in the basin. Albuquerque, among others, was greatly affected by this basin closure since the city relied solely on ground water for its current and future supply. Although the pre. 1956 level of ground water consump- tion was deemed a valid right, new water rights would have to be obtained from alternate sources. This provided incentive to initiate a trans~ mountain diversion project to import water from the Colorado River basin. The Middle Rio Grande Conservancy DIstrict found itself challenged by the water management forces working within the basin in the 1950s, To help ease its burden, the District board decided to contract with the Bureau of Reclamation on a number of mat- ters. By 1956, the District had trans, ferred to the Bureau the responsibil- ity for operating MRGCD facilities, including EI Vado Reservoir. The Bureau also assumed the indebted- ness of the MRGCD and paid off the millions of dollars owed by the Dis- trict on the bonds it issued in the 1930s. (MRGCD must repay the Bureau for this assumption as well as for Bureau work undertaken within the District. The District currently owes the Bureau more than $8 million with an interest-free annual repay- ment obligation of around $400,000.) THE FLOOD CONTROL ACT OF 1960 The Flood Control Act of 1960 brought a measure of relief to the water managers of the Rio Grande basin. The Act authorized two addi- tional reservoirs as part of the Middle Rio Grande Project. GaBsteo Dam was completed in 1970 to control sum~ mer flooding and sediment deposi- tion from Galisteo Creek, while Cochiti Dam became operational in 1975 as a mainstem flood control structure and recreational site. Cochiti, with a total capacity of 602,000 at when completed, was one of the ten