The easy answer is that it comes from the sky. But, where does your water really come from? Surprisingly, California residents enjoy water from all over the state depending on the area in which you live. As a whole, about 30% of California’s total water supply comes from groundwater. This number goes up to about 60% during a drought.

But what about San Jose residents? San Jose’s groundwater is pumped from over 100 wells that draw directly from the Santa Clara Groundwater Basin, which accounts for about 40% of the water supply our customers receive. You might also be surprised to know that although some of our local streams and rivers provide us with drinking water, our region’s water is also imported from the Delta, which is fed by the Mokelumne, Tuolumne, Sacramento, and Feather rivers.

We also deliver water collected from the lakes and reservoirs we maintain in the Santa Cruz Mountains, where surface water is collected, transported and treated at our two water treatment plants. Local surface water accounts for approximately 10% of our water supply.

Knowing where your water comes from helps our customers understand the complex nature of the water industry and the role we all play in helping to preserve and protect our water supply. To learn more about your specific water source, check out this map.