The 10 reservoirs operated by Valley Water are highly visible elements of the water supply and flood protection programs for Santa Clara County.

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Stevens Creek Reservoir

Fast facts:

Valley Water operates 10 reservoirs in Santa Clara County.The reservoirs have a total storage capacity of approximately 170,000 acre-feet (One acre-foot is enough water for two families of five for one year.)The reservoirs, which were constructed in the 1930s & 1950s for water conservation (not flood protection) catch storm runoff that otherwise would flow into San Francisco Bay.The reservoirs vày also provide incidental flood protection by containing runoff early in the rainfall season, serve recreational needs, và benefit the environment by storing water lớn maintain flow in the creeks.

Valley Water has a number of water rights associated with its reservoirs và stream diversions. Valley Water has created a website lớn comply with Section 933(b)(4) of California Code of Regulations, Title 23, Division 3., Chapter 2.8, which was an outcome of California Senate Bill No. 88 (SB-88):

Almaden Dam and Reservoir

Almaden Reservoir is one of Santa Clara County"s six original reservoirs, built in 1935, and is one of 10 current reservoirs operated by the Santa Clara Valley Water District. Able khổng lồ store 1,590-acre feet of water, the reservoir, located 12 mile south of San Jose, produces about 4 percent of the district"s local water supply & also provides water for groundwater recharge.

Its accompanying earth fill dam stands 110-feet tall with a crest of about 500-feet. Subject to safety regulations by the State Division of Safety và Dams (DSOD), Almaden Dam is currently considered a high-hazard dam due to the number of people who live in the potential flood zone downstream & the extensive amount of damage that a flood could cause in case of a dam breach.

The seismic project

In 2000, the water district launched the Almaden Dam Improvements Project to address sediment accumulation at the dam"s intake structure & correct aging outlet works infrastructure. In 2005, a seismic stability evaluation for the dam halted the planning phase and while the findings in 2012 indicated the embankment is stable, the dam will still require work khổng lồ ensure its long term reliability. The project, currently in design phase, will:

Modify or construct a new intake structure lớn meet DSOD regulatory standards.Reconfigure the spillway as the result of potential findings from the reservoir"s future probable maximum flood investigation.Correct ongoing operation và maintenance issues lớn aging hydraulic lines, valves & energy dissipaters.

In 2016, Valley Water"s Board of Directors approved a consultant amendment lớn perform improvements khổng lồ the Almaden-Calero Canal in addition to lớn the already approved consultant agreement for improvements at the Almaden Dam. However, project improvements are on hold until Valley Water completes improvements at the Anderson, Calero và Guadalupe dams. 

For more information, contact Public Information Representative Tony Mercado at 408-630-2342 or at  

Innundation mapsInundation bản đồ of Hypothetical Fair Weather Failure of Almaden Dam (2019) (index map)Inundation map of Hypothetical Inflow thiết kế Flood Failure of Almaden Dam (2019) (index map)

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