Los Alamos Canyon Creek, a

stream A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a strea ...

or arroyo,

tributary A tributary, or an ''affluent'', is a stream or river that flows into a larger stream (''main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which they ...

to San Mateo Creek, in the

Cleveland National Forest Cleveland National Forest is a National forest (United States), U.S. national forest in Southern California that encompasses 460,000 acres/ of inland Montane ecosystems, montane regions. It is approximately 60 miles from the Pacific Ocean, withi ...

Riverside County, California Riverside County is a County (United States), county located in the Southern California, southern portion of the U.S. state of California. As of the 2020 United States Census, 2020 census, its population was 2,418,185, making it the fourth-most ...

. Its source is at an altitude of 2300 feet, in a canyon on the south face of the ridge of

Elsinore Mountains The Elsinore Mountains are a ridge of mountains within the larger range of the Santa Ana Mountains, in the Cleveland National Forest, Riverside County, California, United States. the tallest peaks within the range is the unofficially named San Mate ...

that descends to the southeast from

Elsinore Peak Elsinore Peak is a named summit, at the southern end of the mountain ridge running southeast from the vicinity east of El Cariso in the Elsinore Mountains, in Riverside County, California in the United States The United States of Americ ...

. The creek descends southward for a short distance then turns southwest for 4 miles where it turns west for 3 miles down Los Alamos Canyon to its confluence with San Mateo Creek at an elevation of 1312 feet. Los Alamos Canyon Creek has one named tributary Wildhorse Canyon Creek but has two unnamed arroyos descending from the Elsinore Mountains. and one that drains the western

Santa Rosa Plateau The Santa Rosa Plateau is an upland plateau and southeastern extension of the Santa Ana Mountains in Riverside County, California. It is bounded by the rapidly urbanizing Inland Empire, California, Inland Empire cities of Murrieta, California, ...

and the east slope of the Tenaja Mountain

highland Highlands or uplands are areas of high elevation such as a mountainous region, elevated mountainous plateau or high hills. Generally, ''upland'' refers to a range of hills, typically from up to , while ''highland'' is usually reserved for range ...

and descends to the north to join the creek where it turns to the west.Unnamed arroyo draining east slope of the Squaw Mountain highland and western Santa Rosa Plateau, USGS Map Name: Wildomar, CA, Map Center: N33° 33' 10" W117° 20' 33" from topoquest.com accessed on 5/4/2013
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References

{{Reflist Los Alamos Canyon Creek Los Alamos Canyon Creek Los Alamos Canyon Creek Rivers of Southern California