City & Cty. of Denver v. Consol. Ditches of Water Dist. No. 2Annotate this Case
The purpose of the "1940 Agreement" at issue in this appeal was to resolve the parties’ disputes regarding seepage and evaporation losses from three of the City and County of Denver’s streambed reservoirs located on the South Platte River. Under the 1940 Agreement, in lieu of making releases from the streambed reservoirs to replace seepage and evaporation losses, Denver agreed not to reuse or successively use return flows from water imported from the western slope and used in Denver’s municipal water system. Earlier litigation in Case No. 81CW405 established that this reuse prohibition in the 1940 Agreement applied only to return flows derived from decreed water rights from Colorado River sources with appropriation dates before May 1, 1940 (the date Denver entered into the agreement); Denver could therefore use return flows derived from sources that were appropriated or acquired after that date. The question in this appeal was whether the 1940 Agreement prohibited Denver from using return flows from water imported from the Blue River system under exchange and substitution operations that use water stored in the Williams Fork Reservoir under a 1935 priority as a substitute supply. In a written order, the water court resolved competing motions in Denver’s favor, ruling that Denver’s Blue River system water, which was decreed in 1955 with an appropriation date of June 24, 1946, was a source of water that was not owned, appropriated, or acquired by Denver prior to May 1, 1940, and therefore was not subject to the 1940 Agreement. The water court thus held that Denver could reuse or successively use imported water attributed to the Blue River system. Consolidated Ditches and other opposers appealed. The Colorado Supreme Court concurred with the water court, finding the return flows were not subject to the 1940 Agreement and Denver could reuse or successively use those return flows.