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Issue 1 THE LA PLATA RIVER COMPACT 113 B. WATER ROTATION The authors of the Compact provided for a water rotation mechanism for the express intent of maximizing the beneficial use of limited water supplies in the La Plata River.'I Review of historic La Plata River Compact Administration Reports indicate the practice enjoyed varying degrees of success in terms of increased irrigated acreage and crop production, particularly to ditches that are junior in priority." However, mutual agreement by both state engineers as to the mechanics of the rotation, including: specifics of when each rotation would begin and end, the length of each rotation (typically seven, ten, or f01,lrteen days), and which state would be en tided to the first rotation, was often very difficult to establish. The decision making process for representatives of both states required an intimate understanding of the daily physical and hydrologic demands and an innate ability to ,forecast water user needs, streamflows, and weather patterns. The reports of the La Plata River Compact operations are replete with examples in which the timing and duration of rotations was critical. For example, in 1936, Colorado completed a nine-day water rotation on July 3 that resulted in such a dramatic decline in base streamflows thaUhe stream channel became dry for several miles and the only water available to New Mexico during its rotation was minimal accumulated seepage and return flows from irrigated lands in the lower part of the basin." Conversely, on May 10, 1955, New Mexico commenced a fourteen day rotation that provided full water supply to its users, much to the chagrin of Colorado because the anticipated increase in flows during spring runoff never materialized and Colorado water users were left wanting.64 In recent years, Compact administration officials have not implemented a rotation schedule and instead have operated in accordance with delivery obligations by providing one-half of the streamflow at Hesperus to the state line. Nevertheless, the implementation of a rotation schedule has proven beneficial for all water users in the La Plata River Basin and its use under appropriate conditions is anticipated to resume. 61. See La Plata R;iver Compact, COLO. REv. STAT. art. 11(3), ~ 37-63-101 (2001),43 Stat. 796, 797. 62. Report of the:La Plata River Compact Administration, prepared by the Division VII Irrigation Engin~er 1-5 (1929). The term junior within the priority system implies subsequent construc;tion of those ditches that diverted water for application to beneficial use at a later date compared to structures that preceded them. 63. Report of the La Plata River Compact Administration, prepared by the Division VII Irrigation Engineer 4 (1936). 64. See Report o~ the La Plata River Compact Administration, prepared by the Division VII Irrigation Engineer 11 (1955).