ARVIN-EDISON WATER STORAGE DISTRICTSOUTH CANAL IMPROVEMENT PROJECT

摘要

In the 1990’s Arvin-Edison Water Storage District (A-E) developed a water managementpartnership with Metropolitan Water District of Southern California (MWD) in whichA-E would “bank” excess surface water supplies for MWD. MWD is then able to call onA-E to return this banked water at a later date, typically during drought conditions. Overthe past decade this program has proven to be successful for both A-E and MWD.Besides the water supply benefits of the program, MWD has received an unanticipatedwater quality benefit from the program. However, conveyance capacity limitations inA-E’s South Canal have proven to be a bottleneck in the long-term effectiveness of theprogram for both partners.In 2001, MWD secured $20 million in grant funding from the State of California todevelop programs and projects which create a water quality benefit for MWD. MWDdeveloped partnerships with various agencies and commissioned several studies toinvestigate various programs and projects to do so. In 2004 A-E, through a MWD fundedpartnership, commissioned a study to develop alternatives which would increase thecapacity of the South Canal, and address the bottleneck in existing “forward flow”capacity. The study also investigated the feasibility of adding “reverse flow” capacity tothe South Canal by utilizing gravity flows coming from A-E’s turnout off of theCalifornia Aqueduct. Out of 18 programs and projects investigated, with variousdistricts, MWD determined that A-E’s South Canal Improvement Project (SCIP) was theonly construction project which would provide water quality benefits to MWD and couldbe completed within the time-frame and budget of the grant funding.In 2006, A-E and MWD worked to amend the existing program to subsequently storemore MWD water in A-E and to allow A-E to return more water to MWD through theSCIP. This paper will discuss the analyses associated with increasing the forward andreverse flow capacities of the South Canal, various design considerations, projectfunding, scheduling, construction and constructability issues, and the operational benefitsto both A-E and MWD.