Download: Fact Sheet: Delivery of Water(PDF)
WHAT: There are two primary sources of water in California: groundwater and surface water.
Groundwater is that water which falls as rain and is absorbed into the ground where it become part of the water table or “aquifer.” Ground water is pumped out of the aquifer to be used for agricultural, residential and commercial uses. During an average year, 40% of California’s water supply comes from groundwater. In times of intense drought, ground water consumption can rise to 60% or higher. While large groundwater reservoirs are found in the Central Valley, there are no significant/usable groundwater reservoirs at Diablo Grande.
The community of Diablo Grande is dependent on surface water. Surface water includes water from streams, rivers, lakes, wetlands, or even the ocean.
HOW: Surface water delivered to Diablo Grande originates in the Sierra Nevada mountain range. Rainfall and the melting snowpack in the mountains flow into streams and rivers which ultimately make their way into the Sacramento–San Joaquin River Delta (aka the Delta), an expansive inland river delta and estuary formed at the western edge of the Central Valley. From the Delta, water is conveyed throughout areas of California via a state-wide water delivery system of canals, tunnels, pipelines, and aqueducts, including the California Aqueduct.
It should be noted that lack of water during times of drought (combined with environmental programs to protect salmon, Delta smelt and longfin smelt) reduce the pumping of water out of the Delta and into the California Aqueduct.
WHO/WHERE: The water for Diablo Grande is provided from the California Aqueduct via a metered turnout located near the corner of Lower Oak Flat Road and Interstate 5. Raw water for the community is pumped uphill through a series of four raw water pump stations. From the last raw water pump station, water can either be routed to the Diablo Grande Water Treatment Plant or sent to the golf course.
Raw water for irrigation of the golf course at Diablo Grande is put into ponds and then pumped out and into the golf course irrigation system. Water intended for residential use and the maintenance of common area landscaping (including parks and front yards in some residential neighborhoods) is potable water (or water treated to drinking water standards) and is distributed to the Diablo Grande community on an “as needed” basis. Water from the Diablo Grande Water Treatment Plant is stored in a 1 million gallon storage tank located on a hill above the existing neighborhoods of Diablo Grande. Water flows downhill from this tank to the community.