Section5_Gap_11-7-07 - Laserfiche WebLink

Home Browse Search

Section 5 M&I Users Addressing the Water Supply Gap Technical Roundtable There will be losses in the delivery of water J from the point of diversion to the final end user as conceptually shown in Figure 5-16. Firmin= Losses include historical ditch seepage and (evapc~, seepagz, irrigation returns, evaporation, and seepage from firming reservoirs, water lost during the water treatment processes and evaporation and seepage in terminal reservoirs before delivery to local water treatment facilities. The conjunctive use (CU) of nontributary groundwater as part of this alternative can potentially improve overall project operations. Under this concept, during . above average years when agricultural rights are yielding more, additional surface water can be recharged into the Conveyance Figure 5- Schematic of Losses from Diversion to End User for Agricultural Transfer Alternati Water treatment processes are significantly more complex and costly for both capital construction and O~SCM. Reverse osmosis is shown in this schematic for treating the high TDS water though there are other potential treatment processes that may meet some or all of the end user water quality goals and drinking water standards. An advanced oxidation process with side-stream softening is shown for treating water with a high percentage of municipal or agricultural return flow that typically has higher levels of dissolved organics and hardness nontributary aquifers for later withdrawal. During conditions of below average streamflow, when surface water agricultural water rights are producing less, the water stored in above average years can 16 be withdrawn from the a uifers to rovide an q P ve additional dry year yield. Additional pipeline, pumping, and treatment capacity would be required, but there would be a potential reduction in the volume of storage required. This CU concept has not been analyzed and would require additional investigation on the aquifer storage and recovery concept. A schematic of a CU surface water and groundwater aquifer storage and recovery layout is shown in Figure 5-17. Additional information regarding potential groundwater storage opportunities can be found in two studies: ~Irtficial Recharge of Ground Water inColorado - ~I Statetivide~Issessment (2004) prepared by Ralf Topper, Peter E. Barkmann, David A. Bird, and Matthew A. Sares for the Colorado Geological Survey, Department of Natural Resources; and, SB06-193 Underground Water Storage Study (2007) prepared by CDM for the Colorado Water Conservation Board. FINAL DRAFT 5-23