After Half a Century City of Cortez Point of Diversion Change

Cortez’s water rights date back to 1892, when the Dunham & Johnson Ditch, Giogetta Ditch, Illinois Ditch, and Sheek Ditch were decreed for irrigation on the Dolores River above the town of Dolores. Appropriations from these ditches began between 1879 and 1883 by diversion to beneficial (irrigation) use. Original untreated domestic diversions to Cortez came from the Montezuma Valley Irrigation Company (MVIC) and several predecessor entities that diverted water from the Dolores River into Main Canal No. 1. This canal carried the water to their mile long tunnel, completed in 1889, under the divide into the Montezuma Valley in the McElmo & San Juan drainage basin. Later in 1952 and 1953, the town purchased the four irrigation water rights above, changed their point of diversion to the MVIC Main No.1 and started diverting into their new water treatment plant for distribution to the City of Cortez. By 1987 the U.S. Bureau of Reclamation’s Dolores Project (DP) had constructed McPhee dam, a new tunnel, and filled the old abandoned tunnel. All MVIC and Cortez water diversions from the old Main No. 1 were then diverted by the newly constructed inlet and tunnel within McPhee Reservoir instead of directly from the Dolores River and uses continued on as before.
Last year, however, a Colorado Division of Water Resources engineer discovered that Cortez never filed an application to officially change its point of diversion from the old MVIC Main No. 1 Canal to the DP Dolores Tunnel. In an effort to rectify this early 1950s oversight, the town filed an application to change the point of diversion in June of 2012. As in any change case, there were those who owned water rights that could potentially be injured, including MVIC and the Dolores Water Conservancy District. The DP contracted operator filed Statements of Opposition to the change case. As long time neighbors and cooperators, all parties were able to amicably work out language that protected the City’s priority of right and continued their historical 4.2 CFS diversions and uses. The opposing parties were satisfied that no expansion to decreed use or quantity was granted in the change case.