The federal reserved water rights doctrine provides that, when the federal government withdraws land from the public domain for particular purposes, it simultaneously acquires the right to sufficient water to effectuate those purposes. The initial reservation for the Black Canyon of the Gunnison National Monument was established by proclamation of President Herbert Hoover dated March 2, 1933, under the authority granted to the President by the Antiquities Act of 1906. On December 23, 1971, the United States – through the National Park Service – filed an application in Water Division 4, seeking “confirmation of its rights to the use of . . . water rights appurtenant to the Black Canyon of the Gunnison National Monument.” In 1978, the water court entered a decree for an unquantified conditional water right for the Black Canyon. On January 17, 2001, the United States filed an application in the water court seeking to quantify the reserved water right for what had become the Black Canyon of the Gunnison National Park. The application was in the form of an application to make a conditional water right absolute. The application sought adjudication of a base instream flow plus a one-day peak flow, both in amounts to be determined annually according to a formula based on inflows to Blue Mesa Reservoir, with a priority date of March 2, 1933. The volume of water sought by the application, together with a 1933 priority, created the risk of curtailment of a majority of the water rights in the Upper Gunnison Basin in even moderately dry years. 386 Statements of Opposition were filed in the water court during the permitted period following the application.

During the Summer of 2007, after almost six years of litigation in state and federal courts, a committee comprised of the principal opposers, including the District, and the United States developed a protocol for mediation of the case, agreed on a cost sharing agreement for the mediation, and selected a professional mediator. Mediation sessions commenced on September 21, 2007 and lasted for nine months. More than 60 people, representing the federal government, state agencies, local interests, conservation groups, water users, and power customers participated in the mediation. The mediation resulted in a stipulated decree which was entered by the water court on December 31, 2008 (Case No. 01CW05). In addition, the District negotiated individual stipulations of withdrawal with the United States on behalf of individual water users not represented by counsel. The water users agreed to withdraw in exchange for the United States’ agreement to subordinate the Black Canyon water right to all water rights with adjudicated priorities that are senior to the Aspinall Unit water rights. The stipulations also limit the benefits of the subordination to in-basin uses and reaffirm the Aspinall Subordination Agreement. The decree provides a series of formulae that derive the flows from forecasted inflows to Blue Mesa Reservoir under six hydrologic conditions (from dry to wet), defines minimum flows and an annual 24-hour peak flow based on hydrologic conditions, and contains limitations on the exercise of the Black Canyon water right, including the following:

  • The decree shall not be exercised to affect operations under existing federal contracts (e.g. 1975 Taylor Park Agreement).
  • Peak flows will be reduced under defined drought conditions to allow recovery of Aspinall Unit storage
  • The water right will be exercised with due regard for the fishery in the Gunnison River.
  • To the extent practicable, the water right will be exercised so that peak flows are coordinated with releases from the Aspinall Unit made to protect listed species in the Gunnison River and their

In addition, the United States agreed to subordinate the Black Canyon water right to all existing in-basin junior water rights and to subordinate the water right to future in-basin development allowed under the Aspinall Subordination Agreement.