Water Recharge Into Central And East Valley Acquifers At A 32-Year Peak

The regional water table over the last 12 months has experienced a level of natural recharge that has not taken place for 32 years, according to the San Bernardino Valley Water Conservation District.
During the 2018-19 Water Year, which runs annually from October 1 to September 30, the level of snowmelt and rainfall, taken together with imported water obtained from the State Water Project and other sources that either percolated or was injected into the East Valley and Central Valley aquifers, resulted in a total net recharge of 70,000 acre-feet, reflecting a number not seen since 1987. That recharge was conveyed into holding ponds, and seeped naturally through silt and sand into the groundwater basin for future use.
San Bernardino Valley Water Conservation District General Manager Daniel Cozad attributed the success of this water year to a very wet winter and several local cities and water agencies having established in 2018 the Groundwater Council, through which they pledged to contribute what they deemed to be a fair share of imported State Project water for local storage.
The water stored so far this year is enough to serve 210,000 families for an entire year, Cozad said, but it is being saved to help make up for significant overdrafts in the past.
“Our region is blessed with large underground aquifers that can store significant amounts of water for use in times of severe drought,” Cozad said. “Thanks to our partner agencies on the Groundwater Council, we have been hit by a double-windfall of heavy precipitation and unprecedented collaboration to store as much water as we can.”
The San Bernardino Valley Groundwater Council is what Cozad termed a 21st Century model for cooperation, where member agencies pitch in their fair share of water for recharge or contribute money for the purchase of imported water to achieve optimum levels of water storage in the San Bernardino and Bunker Hill groundwater basins.
Participation in the council is open to all groundwater producers in the San Bernardino Basin Area. Current members include the East Valley Water District; the cities of Colton, Loma Linda and Rialto; the San Bernardino Municipal Water Department; the Fontana Water Company; the San Bernardino Valley Municipal Water District; the San Bernardino Valley Water Conservation District; and the Yucaipa Valley Water District.
The last time the region stored this much groundwater was in 1987, following a period of successive wet winters. Prior to that spell, 22.8 million gallons of storage had not been achieved since the late 1940s.
This year’s significant degree of water storage comes on the heels of two other years of significant recharge.
The 2017-18 water year reflected the highest streamflow recharge level in five years at 16 billion gallons – the 16th highest recharge amount since the district started recording measurements 106 years ago.
The 2016-17 water year’s total was 236 percent above average.
Previous years of substantial streamflow recharge include: 2011 (53,986 acre-feet); 2010 (30,565 acre-feet); 2005 (56,980 acre-feet); 1998 (55,576 acre-feet); and 1995 (35,876 acre-feet). The record year for water recharge in the district was in 1922, when 104,545 acre-feet of water was captured in retention ponds where it was allowed to filter underground.
From 2012 to 2016, San Bernardino County, Southern California and California experienced a four-year drought.
Since 1912, the San Bernardino Valley Water Conservation District has conserved more than one million acre-feet or 326 billion gallons of water by diverting the natural flow of the Santa Ana River and Mill Creek into 71 percolation basins that allow the water to collect and permeate naturally into the ground, where it can be pumped out for future use.

Leave a Reply