2011-11-28_HYDROLOGY - M1988112 (2)

Home Browse Search

Colorado Division of Water Resources June 23, 2011 Page 7 release in the wintertime. This will allow for sufficient augmentation credits to be available to offset all depletions to be incurred under this SWSP. Table A -3 in Appendix A shows how depletions will be offset with augmentation credits. Because BMRI will be pumping the wells to store excess consumptive use credits and also to irrigate land under the West Pivot, BMRI proposes not to exceed the historical diversions of 695 ac -ft/yr, as quantified in the LWS Expert Report for 07CW42. Given that only the West Pivot will be irrigated in 2011 and that BMRI will only pump excess historic consumptive use credits (approximately 80 percent of diversions for sprinkler - irrigated land and 50 percent for flood - irrigated land), well pumping is expected to be considerably less than this maximum. In addition, BMRI has available to it the augmentation water from Rocky Mountain Farms well 8324 (183 ac -ft/yr) should additional augmentation water be required during the term of this SW SP. Water can be delivered from this well via pipeline to a discharge to Rito Seco immediately upstream of the Salazar Ditch headgate. Therefore, Permit No. 8324 can serve as a backup augmentation source should all of the available augmentation supplies described above not cover the depletive effect associated with the West Pit pumping and precipitation/storm water runoff capture replacement obligation. The annual volume available from Permit No. 8324 (183 ac -ft) is greater than the total annual augmentation requirement; therefore, this well could potentially cover all depletive effects, if necessary. Since the historic consumptive use on the Salazar Ranch is greater than the expected depletions associated with pumping from the West Pit and the alluvium, as well as the precipitation/storm water runoff capture replacement requirement, only a partial dry-up of land is needed to provide the necessary augmentation credits to offset year -round depletions. BMRI reserves the right to use excess historic consumptive use credits on the reduced irrigated area at the Salazar Ranch and/or store these credits for winter augmentation releases. BMRI also reserves the right to continue irrigating at the Salazar Ranch with the remaining water not needed for augmentation subject to the consumptive use cap of 526 ac- ft/yr. SWSP ACCOUNTING BMRI currently has monthly augmentation plan accounting forms that it submits to the Division 3 office pursuant to the decree in Case No. 99CW057. BMRI proposes that these forms be modified to accommodate the change in BMRI operations being sought in this case. This includes accounting for how water is stored, water use of existing rights, dry up of lands to provide augmentation credits, West Pit depletions caused by its use, precipitation and storm water runoff capture replacement obligations, and how the depletions will be replaced to Rito Seco to prevent injury to vested rights of others downstream of the Salazar Ranch. It also includes quantifying the available historic consumptive use for 3 periods, including a) early season (April and May), b) mid - season (June