MONTCLAIR, CA– On April 29, 2024, Chino Basin Water Conservation District’s (CBWCD’s) percolation basins began receiving approximately 19,000-acre feet of water from the California State Water Project via Metropolitan Water District of Southern California (MWD) and the Inland Empire Utilities Agency (IEUA), equivalent to 6.2 billion gallons of water that will fill CBWCD’s percolation basins to replenish the Chino Basin aquifer. Recently, the Department of Water Resources announced an increase in allocation from the State Water Project from 30 to 40 percent due to this year’s healthy Sierra Nevada Snowpack. It will take up to eight months to complete this water delivery, and CBWCD’s basins are scheduled to be banking imported water from the Sierras through December 2024.

“Chino Basin is among the largest groundwater basins in southern California, and certainly one of the most actively managed and studied.  Consisting of about 235 square miles of the upper Santa Ana River watershed, investments have been made to protect and enhance this basin and support the evolving needs of the region,” stated Michael Camacho, IEUA Board member and MWD Director. “An increase in imported water allocation for aquifer storage and replenishment enhances the current reliability of local groundwater supplies for a rapidly growing population. In my roles on both IEUA and MWD’s Board of Directors, I am privileged to advocate for and support our region’s imported water needs, which is critical to our local water supply planning.  However, with the extreme weather swings we have experienced, most notably the recent historic three-year drought, we must remember that the time is always now to use water efficiently in order to preserve our precious water resources.”

Communities served by the Chino Basin, including Chino, Chino Hills, Fontana, Montclair, Ontario, Rancho Cucamonga, and Upland, depend on this aquifer for more than 50% of their water supply. One acre-foot is enough water to provide for approximately three families for an entire year.

The delivery is being made through the Groundwater Recharge Program partnership which includes IEUA, CBWCD, Chino Basin Watermaster, and the San Bernardino County Flood Control District (SBCFCD) who work diligently to import, monitor, and supply water to the local area.  Approximately 21,000-acre feet of imported water will be received by recharge basins in the IEUA service area, with 19,000-acre feet received by CBWCD basins and the remaining received by SBCFCD owned basins.

Storing this imported water is an essential part of the CBWCD’s mission, which is to put water back into the aquifer by capturing it and allowing it to soak into the ground where it is kept safe for later use. The Chino Basin aquifer is our area’s “piggy bank” to store water to use during droughts and the hot summer months. This 6.2 billion gallon delivery will percolate in the Chino Basin aquifer over the next couple of months and will provide water to thousands of residents in San Bernardino County who use an average of 143 gallons of water per day.

“California has a tendency to cycle between wet years and dry years, and when we have a wet year, we hear folks asking about how we are capturing that rainwater and snow melt – this is water storage in action,” said Mark Ligtenberg, President of the Board for Chino Basin Water Conservation District. “Our community had the foresight to invest in this infrastructure when they founded CBWCD in 1949. There’s no better way to celebrate our 75th anniversary than by banking this water for the communities we serve.”

If you would like to learn more about CBWCD’s percolation basins or the State Water Project allocation increase , please visit or For ways to save water and regional rebate and water-use efficiency program information, visit

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