Enhanced Recharge Project: Putting Stormwater to Good Use
The San Bernardino Valley Municipal Water District (Valley District) provides roughly 25% of the region’s water needs from Yucaipa to Fontana. Businesses and residential customers alike depend on them for water. With a limited water supply, unknown annual precipitation amounts and a growing population, water districts in Southern California need to plan to ensure water reliability and security. To meet the future demand, improvements to infrastructure, new pipelines and groundwater recharge systems are being built to gain water independence.
The Enhanced Stormwater Capture and Recharge Project (Recharge Project) on the Santa Ana River is the first stage of improvements made by Valley District and Western Municipal Water District to capture beneficial stormwater that are located downstream of the Seven Oaks Dam. Rather than losing water to evaporation and runoff, with only a portion of it benefiting local groundwater basins, the Recharge Project uses Santa Ana River water to replenish basins that seep into groundwater basins that are later pumped and conveyed to local agencies.
The Recharge project aims to divert up to 500 cubic feet of water per second and recharge up to 80,000 acre-feet of water per year. This amount reflects 3740 gallons of water diverted per second, and over 26 billion gallons recharged in a single year. These valuable gallons of recharged water will replenish groundwater supplies by ensuring it goes back into aquifers. In addition to costing less to store, recharge water also has smaller amounts of evaporation being that it is underground.
The groundwater that is being stored underground is called an aquifer. Aquifers are made up of layers of sand, rock, soil, or gravel where water is saturated and stored. It permeates through the spaces and gaps between the sediment. This water can be accessed when needed through drilling wells and pumping. Water that is stored underground is vital to the region’s overall water portfolio and after being pumped reflects about 72% of the available water supplies to meet growing demands.
The Recharge Project plays an important role in keeping groundwater supplies recharged. As water is pulled from the aquifers to be used, more needs to be added in order to keep a balance. If too much water is used without being recharged, the aquifer will become dry. The water in aquifers is vital to our survival by providing drinking water, irrigation supplies, freshwater needs, and to serve as an emergency supply. The Recharge Project supports water districts in the San Bernardino Basin and Southern California to help reduce reliance on more expensive imported water sources. By utilizing stormwater that is captured locally, districts are able to provide commercial and residential customers with their water supply
In addition to capturing the Santa Ana River stormwater at Seven Oaks Dam, the Recharge Project includes a debris removal system component, a sedimentation basin, canal, pipeline, and recharge basin. Each of these improvements increases the availability of local water supplies and creates less dependence on outside water sources.
With the population of the area growing and unknown annual precipitation, water districts across Southern California continue to research, develop and implement innovative ways to provide customers with reliable tap water as made available through the Recharge Project.