Santa Teresa Water Treatment Plant Sedimentation Basin in Almaden Valley
Photo Note: That green tint in the water is actually the algae that grows due to the high-nutrient discharge of farm runoff into the Delta and then concentrated in San Luis Reservoir. When the depth gets low enough, as it is now, the light penetration causes the reservoir to bloom. In order to avoid objectionable taste and odors in our drinking water, we must remove the algae at our local treatment plants, using expensive carbon filters. Think a 100 million gallon per day Brita filter.
Our first taste of imported water in Santa Clara County was almost free to the Santa Clara Valley Water District. Since investor-owned water companies, like San Jose Water Company, were blocked by federal legislation from purchasing water from San Francisco's Hetch Hetchy Aqueduct, cities along the South Bay's shore formed municipal water departments and contracted directly with the San Francisco Public Utilities Commision to buy water. Today, those contracts supply 15% of the county's water, although the cost of that supply will rise 400% to pay for the $4 Billion in bonds sold by SF to rebuild most of the 90-year-old system.
This situation would present a problem for the Santa Clara Valley Water District if those municipal water departments began pumping cheaper groundwater into their service areas to avoid paying the higher costs for Hetch Hetchy supply. However, the price gap will be short-lived as the price for the Water District's supply will be increasing at a similar rate over the next decade or two, and billions of dollars are expended both inside and outside the county to continue to obtain another 40% of our water supply from the Sacramento-San Joaquin River Delta.
While Proposition 1 was passed last November by the State's voters, allowing sale of $7.5 billion of bonds to pay for adding more storage and building local options for water to address future water needs, other infrastructure projects in the Delta were not included in the recent bond measure. These facilities will be part of a fifty-year permit issued as part of a Habitat Conservation Plan (HCP) for Delta ecosystem restoration and water supply reliability. The Bay Delta Conservation Plan (BDCP) recently released a 30,000-page environmental impact document detailing the baseline as it exists today and plans for fixing this broken ecosystem and mitigating the interwoven stressors, which have caused a half dozen native fish species to be listed on the Endangered Species Act. Biological opinions filed by State and Federal Fish and Wildlife agencies caused the pumping by the State and Federal water projects in the southern Delta to be severely curtailed.
The present value estimates for the BDCP program, including new conveyance facilities is $15.4 billion plus $2.3 billion in operating and maintenance costs over 50 years. Santa Clara County will be responsible for about 4% of those costs as their proportional share of the contract entitlements for the water pumped by the State Water Project and the Federal Central Valley Project, as Santa Clara Valley Water District is the only water agency in the state to have contracts with both systems. The Water District estimates that we will spend $228 million locally over the next 10 years to increase reliability of our Delta water supplies.
Santa Clara Valley Water District contracts for water deliveries through both major water diversion projects exporting water from the southern Delta, near Tracy. The South Bay Aqueduct pumps water over the Diablo Range, through Livermore and Pleasanton and terminates near Alum Rock Park in San Jose.
The other aqueduct is called the San Felipe Aqueduct and is a recent (1987) addition to the Federal Central Valley project. Delta water is conveyed to the jointly-owned State-Federal San Luis Reservoir through both the California Aqueduct and the Delta-Mendota Canal and pumped into the 2 million ac-ft off-stream storage facility.
Once Delta water arrives in Santa Clara County, it requires treatment in state-of-the-art treatment plants to remove a broad array of chemical contaminants to bring the quality up to State and Federal drinking water standards. The Santa Clara Valley Water District owns three such plants: a 40-million-gallons per day (MGD) plant named Penetencia in the east foothills near Alum Rock Park, an 80-MGD plant named Rinconada, adjacent to the Los Gatos Golf Club of the same name, and the newest Santa Teresa Water Treatment Plant in Almaden Valley capable of treating 100 MGD.
The combined costs of importing and treating Delta water, delivered by two aqueducts, is currently over $100 million per year. Capital improvement projects planned by the SCVWD will add considerably to this annual cost.
Source: SCVWD 2012 Water Supply and Infrastructure Master Plan
The expansion of the Rinconada Water Treatment plant to 100 MGD
is currently under environmental review and is expected to cost around $200 million.
Existing Rinconada Water Treatment Facility
Recently the twelve 2000 hp pumps at the Pacheco Pumping Plant on the west end of San Luis Reservoir had to be replaced after 25 years of service at a cost of $13 million.
The Water District's surplus Delta water stored in Kern County's groundwater basin will be recovered at an additional cost of $12 million to reverse the flow of the California Aqueduct for about 100 miles, more than tripling the cost of remote water banking from $165/acre-ft. to $565/ac.-ft. That's in addition to the $40 million per year contract costs of the two aqueducts that were suppose to deliver water directly to SCVWD.
Depending on the amount of water delivered annually, the unit costs for using these two conveyance systems ranges from $160 for 250,000 ac-ft to $1,000 if and when only 40,000 ac-ft were available. In 2014, 70,000 ac-ft of Delta water plus 35,000 ac-ft of recovered Semitropic Bank water withdrawal were conveyed through the two aqueducts, for a unit cost of $380 per ac-ft.
As the cost of the Water District’s imported water continues to rise, local reliability projects like water use efficiency and water recycling become the obviously preferable alternative. However, due to what I call "asset inertia" projects intended to increase the reliability of Delta water continue to be funded by the Board of Directors, who seem oblivious to the response to both State and other local agencies who realize it's time to rely less, not more, on Delta water deliveries. After sixty years of a growing reliance on water from remote watersheds, a sensible revision of our local water policy would be to shift immediately to increasing locally controlled supplies.