Big Tujunga Dam
dam in Angeles National Forest, Los Angeles County, California
Big Tujunga Dam is a 244-foot-high (74 m) concrete arch dam in Los Angeles County, California, spanning Big Tujunga Canyon northeast of Sunland, in the foothills of the San Gabriel Mountains. Completed in 1931, it provides flood control and groundwater recharge for the San Fernando Valley.
Its reservoir is called Big Tujunga Reservoir, and collects runoff from a watershed of 82 square miles (210 km2). Although it is located inside the Angeles National Forest, public access to the lake is forbidden. The water is usually kept at a low level, in order to protect against winter floods. The name of the dam is derived from a Tongva village name.
Description
The dam is 208 feet (63 m) high from the riverbed, 244 feet (74 m) high from the foundations, and 830 feet (250 m) long. It has a width of 138 feet (42 m) at the base, tapering to 8 feet (2.4 m) at the crest. The storage capacity is 5,960 acre⋅ft (7,350,000 m3) at the spillway, with a minimum pool of 1,210 acre⋅ft (1,490,000 m3) to prevent sediment and debris from entering the dam's outlets.
After the completion of Hansen Dam downstream, the importance of Big Tujunga Dam for flood control has decreased; however, it is still directly responsible for protecting about 4,600 residents living in the floodplain of Big Tujunga Canyon.
The public source identifies “Big Tujunga Dam” as dam in Angeles National Forest, Los Angeles County, California. This brief keeps that definition visible, then builds a research path around Tujunga, Angeles and National.
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Place names and jurisdictional language are key evidence: both can reveal earlier catalogue descriptions and overlooked record series. The source revision retrieved here is dated Jul 1, 2026. The linked authority identifier is Q4906615. Authority coordinates are 34.293, -118.188. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1931.
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This entry incorporates text from “Big Tujunga Dam” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.