Tujunga Wash

Tujunga Wash, south from Victory Boulevard

Tujunga Wash is a 13-mile-long (20.9 km)[1] stream in Los Angeles County, California. It is a tributary of the Los Angeles River, providing about a fifth of its flow, and drains about 225 square miles (580 km2). It is called a wash because it is usually dry, especially the lower reaches, only carrying significant flows during and after storms, which usually only occur between November and April. The name of the wash derives from a Tongva village name.[2]

About

The name Tujunga or Tuxunga means "old woman's place" in both Fernandeño and Tongva, where Tuxu means "old woman". The term is thought to relate to an ethnohistoric narrative, known as Khra'wiyawi, collected by Carobeth Laird from Juan and Juana Menendez at the Leonis Adobe in 1916. In the narrative, the wife of Khra'wiyawi (the chief of the region) is stricken with grief over the untimely loss of her daughter. In her sadness, she retreats to the mountains and turns to stone. It is thought this event became the basis for the village name.[3] In fact, there is a large rock in Little Tujunga Canyon which looks like an old woman in a sitting position.[4] However, there was also a Fernandeño village in the vicinity of Big Tujunga Canyon 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."

Tujunga Wash consists of two forks, both beginning in the San Gabriel Mountains. The upper portion of Big Tujunga Wash is called Tujunga Creek, or Big Tujunga Creek. It travels roughly east to west, and several tributaries from the north and south join it as it flows to Big Tujunga Reservoir, formed by Big Tujunga Dam. Below the dam, the stream is called Big Tujunga Wash. It continues its westward flow, enters the San Fernando Valley and is met by Little Tujunga Wash a mile before reaching Hansen Reservoir, which is formed by Hansen Dam. Little Tujunga Wash comes from the north, draining the portion of the San Gabriel Mountains immediately north of Hansen Reservoir. Downstream of the dam, Tujunga Wash flows roughly south and is met halfway to its confluence with the Los Angeles River by Pacoima Wash, which drains the other side of the mountains that Little Tujunga Wash drains. Finally, Tujunga Wash meets the Los Angeles River in the Studio City neighborhood of Los Angeles.

Flooding damage along the wash in 1938

The Big Tujunga Dam was constructed by Los Angeles County and completed in 1931. The resulting Big Tujunga Reservoir has a capacity of 5,960 acre-feet (7,350,000 m3). Although the dam was tested during the Los Angeles Flood of 1938, it required a seismic retrofit to meet modern safety standards. Completed in July 2011, the retrofit included doubling the thickness of the gravity arch dam.[5] Downstream, the United States Army Corps of Engineers completed the Hansen Dam in 1940, creating a reservoir capable of holding 74,100 acre-feet (91,400,000 m3).

While the primary purpose of these facilities is flood control, they also facilitate groundwater recharge. However, the efficiency of natural recharge within the watershed is limited by geographical and urban factors. In the upper reaches, high flow velocities prevent significant soil absorption. In the lower watershed, extensive urbanization has replaced bare ground with concrete-lined channels, further inhibiting percolation and resulting in the majority of runoff discharging into the ocean.

In 1969, there was a flood in the Tujunga Wash. Water flowed down a formerly inactive channel and entered a large gravel pit 15 to 23 m (49 to 75 ft) deep. The channel bed degraded by about 4 meters (13 ft), leading to the failure of three highway bridges and the loss of seven homes.[6]

Crossings

From north to south (with year built in parentheses):

See also

References

  1. ^ U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map, accessed March 16, 2011
  2. ^ Suntree, Susan (2020). Sacred Sites: The Secret History of Southern California. University of Nebraska Press. p. 273. ISBN 9781496219558.
  3. ^ King, Chester. Overview of the History of American Indians in the Santa Monica Mountains. Rep. Topanga, California: Topanga Anthropological Consultants, 2011. Print. Prepared for the National Park Service Pacific West Region Santa Monica Mountains National Recreation Area
  4. ^ Johnson, John R. "Ethnohistoric Overview for the Santa Susana Pass State Historic Park Cultural Resources Inventory Project" (PDF). Retrieved 19 July 2020.
  5. ^ McCoy, John (July 21, 2011). "Big Tujunga Dam Seismic Retrofit Project completed". Los Angeles Daily News. Archived from the original on April 25, 2012. Retrieved June 20, 2021.
  6. ^ Bull, W. B. and K. M. Scott (1974). "Impact of mining gravel from urban stream beds in the Southwestern United States." Geology 2: 171-174.

34°08′42″N 118°23′20″W / 34.1451°N 118.3889°W / 34.1451; -118.3889

allikas: https://en.wikipedia.org/wiki/Tujunga_wash