(June 9, 2026)
Our Club member Rob Katherman is one of 5 Board members representing the 5 divisions of the West Basin Water Replenishment District, using groundwater aquifers to create a locally sustainable water supply for the Los Angeles basin. He reviewed measures being taken to deal with increasing pollution and decreasing supply of water in our area. The underground aquifer flows towards our Basin area from the Santa Monica and San Bernardino Mountains. If this water is pumped out to an excessively low level, seawater seeps into the aquifer. Also, sand and fine silt particles can clog filters.
Water barriers were built in 1951, and injection wells to block seawater inflow in 1956. A pilot program plant was built in Torrance in 2001 to clean salty & brown water. The Torrance plant now produces 5 million gallons of fresh potable water daily from our effluent water. The Long Beach plant produces 8 million gallons of recycled water daily (for injection into the Alameda Seawater Barrier in Long Beach to block salt water inflow). Purchasing outside water costs about $3000 per acre foot. A new effluent plant is now being started, to finish in 2028. 5 new wells are being built, with 3500 acre-feet per year. (See information at https://www.wrd.org/.)
The decreasing Colorado River flow is a big problem, with the warming climate, increased evaporation, and less snow cover to provide spring meltwater. The 7 states drawing from it are following an agreement made almost 100 years ago, when supply was higher and demand was lower. How much to allow for each state and how much for agriculture versus residential communities is still being discussed, but water shortages and increasing need for self-sufficiency are important. (The morning after Rob Katherman’s talk, a water main breakage in the Palos Verdes area cut off some water supplies and raised concerns of possible pollution contamination.)