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Other water right issues need to be considered in the study, according to the Non-Federal Parties to the 1975 Agreement. For example, the 300 cfs minimum flow in the Black Canyon below the Gunnison Tunnel is not intended to be met solely from direct flows as stated in the proposed contract. The BOR's stated operating principles for the Aspinall Unit acknowledge the maintenance of a JOO cfs. minimum flow thrnl1O'h thp. Rbrlr r~n'""\n !:I1lo:: ~ ~prlPMl rPli:nnn~:ihi1itv - -', --------"--- ---.. -----0-- ---- ------ --~J~&. -~ - - --_&- &--1'--------.... The operating principles provide that this flow be met through both direct flows and releases from storage in the Aspinall Unit. The BOR has indicated that it anticipates continuing the practice of guaranteeing a minimum flow of 300 cfs in the Black Canyon once the CWCB's instream flow water right is in place. The purpose of the CWCB water right is to protect the natural environment to a reasonable degree, and consequently the instream flow from diversion by junior water rights below the Gunnison Tunnel and within the instream flow reach. The CWCB does not anticipate a need to "call" out juniors upstream of the Aspinall Unit; the 300 cfs minimum flow will already be in the river because of Aspinall operations that bypass water to downstream seniors, generate hydropower, and otherwise maintain a 300 cfs flow below the tunnel. The Black Canyon must quantify its decreed reserved right in District Court for Water Division 4 before any "calls" under a date as early as 1933 can be administered. Bypasses of inflow, other than power operations, from Aspinall to the Black Canyon mayor may not be considered releases of storable inflow from Aspinall. According to the UGRWCD, operations to provide the 300 cfs minimum should continue in such a manner that the 300 cfs instream water right donated by the Nature Conservancy will not need to place a call on water users upstream from Blue Mesa Reservoir. Also, the proposed contract should not result in downstream calls which result in curtailment of Upper Gunnison Basin water supplies or have an adverse impact on water uses and rights in the Gunnison Basin. The effect of the contract on the "1975 Exchange Agreement" should be addressed as well as on other agreements in the basin according to comments received in Montrose. Also asked was how the contract would affect flows in the Uncompahgre River because of the physical and water agreement ties with the Gunnison River. As discussed in Item 10, the proposed contract may affect Colorado's ability to use its Compact entitlement and this should be addressed. Arapahoe County stated that there were both ample flows in the Gunnison River to maintain stream flows in the Black Canyon and to allow Colorado to develop its Compact entitlement. The 300 cfs minimum flow through the Black Canyon is a good alternative for protection of the Black Canyon; necessary studies must be conducted to determine the benefits and potential damages from any greater flows. The Union Park Project is obligated to guarantee minimum flows of 200 cfs from May I through September 30, and 50 cfs from October 1 through April 30. If BOR were to agree to pass these Union Park minimum flows, along with the 300 cfs instream flow through the Aspinall Unit, most of the needed flows would be guaranteed. As mentioned in Item 11, Arapahoe County considers this to be a viable alternative to the contract. At the Gunnison meetings, questions were raised whether or not Arapahoe County could condemn water rights for their project and if BOR could ovenide this. 27 001705