Big Tujunga Dam is a 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 . 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 high from the riverbed, high from the foundations, and long. It has a width of at the base, tapering to at the crest. The storage capacity is at the spillway, with a minimum pool of 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. In addition, the dam conserves about of runoff per year for drinking water and groundwater recharge purposes. This saves the city of Los Angeles about $2,250,000 annually due to the cost difference between local and imported water. Because of the small storage capacity of the reservoir relative to the size of its watershed, frequent dredging is required to remove sediment from behind the dam. Most of the sediment is compacted and stored at the Maple Canyon Sediment Placement Site located less than west of the dam. The 2009 Station Fire, which burned some 87% of the Big Tujunga watershed, caused more than 2 million cubic yards (1.5 million m3) of sediment to flow into the reservoir, all of which subsequently had to be removed. History Aside from the village of Tujunga or Tuxunga (means "old woman's place" in both the languages of the Tongva and Fernandeño), the former Fernandeño (Native American) village in the area of the dam and Big Tujunga Canyon was called Muxúnga, which means "place of shooting" in the Fernandeño dialect of the Tongva language. The name comes from the verb muxú, which means "shoot him." The dam was completed in 1931 by the Los Angeles Department of Water and Power, at a cost of $1.2 million ($ in