PROJ00335 - Laserfiche WebLink

Home Browse Search

I I I I I I I I I I I I I I I I I I I Small Reservoir Feasibility Study S-3 TIlE BASIN COMPUTER MODEL A computer model of basin hydrology and water administration was developed to simulate water deliveries and instream flow conditions under a variety of demand and facility development scenarios. The model represented the Blue River basin and portions of the Colorado River basin as a network of stream reaches, reservoirs, water rights, and water delivery systems and allocated water inflows to specific delivery systems based on the water rights priorities and operating rules associated with each system, The model simulated in detail the operations of all major water rights in Summit County, including Green Mountain and Dillon reservoirs, and the terms of the Summit County Agreement, (Green Mountain Reservoir operations were partially constrained to be consistent with studies done by the USBR in connection with the Water Marketing Program,) Releases from the Historic User Pool (HUP) and the Water Marketing Sales Pool were limited to 66,000 AF Iyr and 20,000 AF Iyr, respectively, Summit County users were assumed to contract for their presently requested allocations of Sales Pool water, Sales Pool exchanges were not permitted to draw reservoir levels below the minimum levels specified by the USBR. Water rights on the Colorado River above and below the Blue River were modeled in an aggregated fashion, although the major senior rights at Cameo and Shoshone were explicitly represented, Denver's substitute sources of water for Blue River exchanges were modeled in aggregated form, The model operated on a monthly time step over a 31-year hydrologic study period corresponding to water years 1952-82. In each month of the study period, the model simulated water exchanges and reservoir operations by a sequence of seven solution steps. These steps are listed in Table S-3, It is important to note that the order of these steps reflects the assumed relative priorities of exchanges, These relative priorities are presently in dispute and may not reflect the views of all study participants, Table S-3 Steps in Basin Model Solution Step 1 Water allocation based on strict water rights priorities Step 2 Out-of.priority diversions by Denver and Colorado Springs ahead of Green Mountain Step 3 Releases from the Green Mountain Historic User Pool (including exchanges) Step 4 Exchanges from Windy Gap and Clayton Hill covered by the Summit County Agreement Step 5 Releases from the Green Mountain Sales Pool (including exchanges covered by the Summit County Agreement) Step 6 Denver exchanges to Dillon, against Shoshone and Cameo calls, from Williams Fork and Muddy Creek Step 7 Green Mountain Reservoir power release adjustment The basin model was calibrated over the period 1975.82 by comparing simulated flows and reservoir contents to historically observed values at eight calibration sites,