Burgeoning California Is Stressing the Water Supply
People have always moved to where the water is, settling near rivers, oases and springs. But a dry, fast-growing Southern California water supplier is bringing the water to where the people are. San Marcos-based Vallecitos Water District, which serves part of San Diego County, is constructing what many call the largest prestressed concrete water-storage tank in the U.S. The 40-million-gallon reservoir will boost the district’s storage capacity by 55%. When completed in 2008, it will be buried in the hills and become nearly invisible.
The reservoir, called Twin Oaks II, is not VWD’s first monster tank. The district completed construction of Twin Oaks I, a 33.3-million-gallon tank, in 2001 at a cost of $16 million. Implementation of the U.S. Environmental Protection Agency’s surface water treatment rule in the mid-1980s forced VWD to take its one open reservoir, 75-million-gallon South Lake, out of service, leaving only 30 million gallons of storage. Since then, the district has worked to enhance its capacity as resources permit. Twin Oaks I was planned as the first of two and possibly three identical reservoirs on the site.