By Nick Diamantides
As the population of Southern California continues to grow and the cost of imported water continues to rise, maintaining an adequate supply of locally produced groundwater becomes more and more critical. On Oct. 7, the Water Replenishment District of Southern California (WRD) hosted its second annual “State of the District” presentation. About 50 people attended the event, which took place at WRD headquarters, at 4040 Paramount Blvd., in Lakewood.
WRD Board President Sergio Calderon and WRD General Manager Robb Whitaker presented local water agency officials and members of the public with an overview of south Los Angeles County’s groundwater condition and highlighted WRD’s smart-water programs, projects and partnerships aimed at conserving water while increasing the amount stored in underground aquifers.
“Fifty years ago, 2.5 million people lived in the District’s service area, which encompasses 420 square miles,” Calderon said. “Today there are four million people in 43 cities.” He noted that in 1960, agriculture was the single largest land use in the region and small dairy farmers constituted the majority of pumpers in the Central Basin (one of the sections of territory overseen by WRD). He explained that, while the agricultural land has been replaced by housing, the dramatic increase in population has caused a sharp increase in water consumption.
“Fifty years ago, there were no legal limits on pumping in the Central Basin, and pumping in the West Basin (the other territory overseen by WRD) was curtailed on a voluntary basis,” Calderon said. “By virtue of pumping more than could be naturally replaced, both basins were in danger of catastrophic collapse.” He added that the depletion of fresh water from the aquifers had also caused seawater to invade both basins, contaminating wells from El Segundo to Long Beach.
Calderon noted that regulations and court rulings strictly define who can pump and how much water they can pump from groundwater supplies in both basins, and WRD makes up the difference between natural replenishment and the water that is legally pumped. “An elaborate system of barrier wells has also put a halt to seawater intrusion, although 650,000 acre-feet of brackish water remains trapped on the inland side of the barriers,” he explained.
Calderon stressed that while WRD’s primary mission to replenish the basins remains the same, its methods have changed significantly in the last five decades. “In the beginning, the water we purchased for replenishment was exclusively imported water from the Colorado River,” he said, adding that in 1962, WRD and county sanitation districts began using recycled water for replenishment.
“Steadily, over time, we have increased our use of recycled water for spreading and barrier injection,” Calderon said. “We have also increased the capture of storm water for replenishment.” He said construction recently began on a pipeline that will connect two WRD water-spreading grounds, enabling the capture of an additional 1,300 acre-feet (423 million gallons) of storm water annually. “That project will be completed in time for the 2010-2011 storm season,” he said.
Calderon also mentioned WRD’s goal of becoming free of imported water for replenishment and barrier injection by 2015. He explained that the WRD Board of Directors took steps toward that goal this year with a series of actions that laid the framework for the Groundwater Reliability Improvement Program (GRIP), a partnership with the Upper San Gabriel Valley Municipal Water District and the county sanitation districts. The program will significantly increase the amount of recycled water used for replenishment. “GRIP will ultimately increase the local water supply by up to 21,000 acre-feet per year– over 6.8 billion gallons annually– for replenishment,” Calderon said.
Underlining the importance of becoming free of imported water for replenishment and barrier injection, Whitaker told the audience that only in 11 of the past 30 years has California experienced normal or above-normal precipitation. “Deliveries of imported water from Northern California and the Colorado River to our area continue to be curtailed due to a combination of drought and judicial rulings,” he warned. “Plans to restore the ecosystem of the Bay-Delta may well result in permanent curtailment of supplies to Southern California.”
Whitaker stressed that the imported seasonal water available for replenishment for the first 47 years of WRD’s history has not been available for the past three consecutive years and will not be available on a reliable basis, if at all, in the future. He explained that, to make up for that shortfall, WRD must use more recycled water and capture more storm water for replenishment and barrier injection. “Local supply must completely replace imported supply,” Whitaker said.
He added that a legally certain framework for groundwater storage must be developed in order to be able to store imported water in the years that it is available. “The 450,000 acre-feet of storage capacity available in the Central and West Coast Basins constitutes the single largest unused water resource asset in Southern California,” Whitaker said. “Efforts to put that capacity to good use have been stalled for decades by institutional and legal conflicts.”
He explained that WRD is currently waiting for the California Court of Appeals to rule on a series of petitions and court hearings pertaining to water storage and extraction rights. Those rulings are expected sometime in 2011. “Without a final determination, our region will not be able to take advantage of storage opportunities during years of imported water surplus and state bond funding for the investments groundwater storage facilities require,” Whitaker said.