Groundwater BasinThe Inland Empire Utilities Agency (IEUA); the Chino Basin Watermaster (CBWM); the Chino Basin Water Conservation District (CBWCD); and the San Bernardino County Flood Control District (SBCFCD) jointly sponsor the Chino Basin Recycled Water Groundwater Recharge Program that is an integral part of the CBWM Optimum Basin Management Plan. This program was put in place to enhance water supply reliability and to improve drinking water quality throughout the greater Chino Basin.

The Groundwater Recharge (GWR) infrastructure consists of a network of pipelines that direct stormwater run-off, imported water from the State of California Water Project and IEUA recycled water to 19 recharge sites, most of which consist of multiple recharge basins. These recharge basins are located throughout IEUA’s service area (approximately 245 square miles) and are designed to hold the water so that it can percolate into the ground, replenishing the alluvial aquifers and groundwater supply.

Annually, IEUA recharges between 40,000 and 50,000 acre-feet of imported water from northern California; between 15,000 and 25,000 acre-feet of stormwater; and 10,000 acre-feet of recycled water. An acre-foot of water is equal to 325,900 gallons of water or equivalent to filling a one acre site that is one foot deep with water.

The Chino Basin Recycled Water Groundwater Recharge Program will assist in mitigating future water shortages in California caused by future limitations for importing water supplies from the California State Water Project and provides a subsurface reserve of groundwater for local use. This enhances the current reliability of local groundwater supplies for a rapidly growing population and is an integral part of the local water supply planning.

The IEUA – GWR Program is an important part of the overall basin program and serves as a long-term solution to the water supply and water quality issues facing the greater Chino Basin. The production of IEUA’s recycled water have been captured and recharged by downstream water agencies for decades. It is now being utilized by the IEUA member agencies and is in accordance with requirements of court-approved basin management plans and peace agreements. The Chino Basin Recycled Water Groundwater Recharge Program has become a nationally acclaimed, award-winning program because it relies on local resources, natural organic cycles, innovative treatment techniques and energy-saving methods.

We do not directly inject water at any of the 19 recharge sites we manage. Instead, we send water to above ground basins and use gravity to slowly percolate the water into the underground aquifer. This allows the soil to act as a natural filtration system, further cleaning the water.