by Diane Merrill, Director, Water
A new California Department of Water Resources report describes the benefits and challenges of using flood water to recharge groundwater aquifers. It highlighted several awardwinning recharge projects in the Kings Groundwater Basin underlying the eastern and central valley areas of Fresno County, and parts of Tulare and Kings Counties. Here is a description from the report with some added language for clarification.
Offsetting groundwater overdraft The McMullin On-Farm Flood Capture and Recharge Project in the Kings Basin was initiated under a Natural Resources Conservation Services grant investigating flooding agricultural lands to mitigate regional flood risks and offsetting groundwater overdraft. The 1,000-acre pilot project studied the infiltration rate of floodwater diverted from the Kings River, potential recharge of groundwater and farm scale logistics. Based upon a 30-year historical record of Kings Basin surplus flood flows, the project estimated 30,000 acres operated for on-farm flood recharge would have had the capacity to capture 80 percent of available flood flows and potentially offset overdraft rates in the Kings Basin. The project was expanded to a regional scale under a DWR Flood Corridor Grant being implemented by the Kings River Conservation District, and with local matching funds from Terranova Ranch. This Phase 1 project included approximately 5,000 acres and was the first phase of a three-phase project to eventually enroll approximately 20,000 acres to divert 500 cubic feet per second of flood flows from the Kings River when available.
Most recently, a U.S. Department of Agriculture’s Regional Conservation Partnership Program award was awarded to Raisin City Water District for the next phase, enrolling approximately 5,000 more acres and implementing the needed infrastructure. Terranova Ranch is a 2017 Governor’s Environmental and Economic Leadership Award winner for the McMullin On-Farm Flood Capture and Recharge Project under the Ecosystem and Land Use Stewardship category