2017-06-30_HYDROLOGY - M2009082 - Laserfiche WebLink

Home Browse Search

Parsons Mine SWSP June 30, 2017 Plan ID 5822 Page 4 of 10 Office of the State Engineer 1313 Sherman Street, Room 821, Denver, CO 80203 P 303.866.3581 www.water.state.co.us diversion was 10,600.2 acre-feet per year, or 33.13 acre-feet per share. Total average annual farm headgate deliveries were found to be 9,010.2 acre-feet per year, or 28.16 acre-feet per share, based on a transit loss of 15% under the Whitney Ditch system. The ditch-wide analysis determined that the overall average consumptive use was 4,400.9 acre-feet per year or 13.75 acre-feet per share, assuming a farm efficiency of 60%. In case no. 2002CW331, 8 shares historically used on 74 acres were previously found to have a river headgate diversion of 33.42 acre-feet per share and a consumptive use of 16.32 acre-feet per share (130.5 acre-feet total). After removing the consumptive use decreed for the 8 shares in case no. 2002CW331, the historical consumptive use for the remaining 312 shares was determined to be 4,270.4 acre-feet, or 13.69 acre-feet per share. For MM’s 12 Whitney Ditch shares dedicated to this SWSP, the total average annual consumptive use would therefore equal to 164.25 acre-feet per year and 337.88 acre-feet of total deliveries. The ditch-wide analysis utilized a return flow split of 50% surface and 50% subsurface return flows. The return flows during the irrigation season will be calculated based upon a percentage of the actual monthly deliveries and winter return flows will be calculated based upon the total deliveries from the previous irrigation season as decreed in case no. 2008CW65. Eight (8) of 12 shares are located within Zone 2-A of the 2008CW65 decree, and the remaining 4 shares are located within Zone 2-B of the 2008CW65 decree. The decreed monthly return flow percentages for Zones 2-A and 2-B are shown on attached Table 2, column 5. The Whitney Ditch water rights will continue to be diverted in priority at the Whitney Ditch headgate during the historical irrigation season of April 1 through October 31. During the period of this SWSP, MM plans to deliver 99.68 acre-feet of Whitney Ditch to recharge ponds and 112.72 acre- feet of the farm headgate deliveries directly back to the river. To date, a single recharge pond has been constructed in the NW¼ of the SW¼ of Section 30, T6N, R66W, 6th P.M. The total surface area of the pond(s) will be limited to not more than 5 acres and will receive water from the Whitney Ditch using MM’s existing headgates and infrastructure located as shown in Figure 3. The IDS AWAS stream depletion model was used to determine the lagged accretion from the recharge pond. The AWAS lagging parameters applied to the proposed recharge pond are shown in the table below. Aquifer Parameters – Recharge Pond X (ft) W (ft) T (gpd/ft) S 3,116 10,205 85,000 0.15 Continuous flow recorders and staff-gauges are required to accurately track daily inflow to the recharge pond. Augmentation credits are based on the amount of water determined to have been infiltrated into the ground based on the change in gage height, less any evaporative losses and plant consumption. The infiltrated water is then lagged to the stream using the AWAS program and aquifer parameters given above. The measuring and recording device used to deliver water to the recharge pond has been approved by the water commissioner; however, a staff gage has not been installed in the pond as required by the SEO’s Recharge Protocol. For this plan period, the Applicant may calculate evaporation from the recharge pond based on the maximum surface area of 5 acres. Credit will not be given for water delivered to the recharge pond under any subsequent SWSP until the water commissioner has approved the installation of a staff gage in the recharge pond and received the stage-capacity table. Net evaporative losses from the recharge pond will be subtracted from the volume of water delivered to the pond every day there is visible water in the pond. For the purpose of this SWSP, you have estimated annual net evaporation using the maximum surface area of 5 acres. Delivery of the projected 99.68 acre-feet to recharge during this plan period will result in 47.70 acre-feet of return flow obligations and 3.58