Cottonwood Creek (San Luis Creek tributary)

Cottonwood Creek
Arroyo Alamo
Location of the mouth of Cottonwood Creek at San Luis Reservoir in California
EtymologySpanish
Location
CountryUnited States
StateCalifornia
RegionMerced County
Physical characteristics
Sourcesource
  locationRed Hill, eastern slope of the Diablo Range, north of Pacheco Pass, Merced County
  coordinates37°07′29″N 121°11′24″W / 37.12472°N 121.19000°W / 37.12472; -121.19000
  elevation2,080 ft (630 m)
Mouthmouth
  location
Confluence with San Luis Reservoir, Merced County
  coordinates
37°06′18″N 121°07′57″W / 37.10500°N 121.13250°W / 37.10500; -121.13250
  elevation
548 ft (167 m)

Cottonwood Creek is a southeastward-flowing 4 mi (6.4 km) tributary stream of San Luis Creek, originating in the eastern foothills of the Diablo Range in Merced County, California. The creek's mouth, before the San Luis Dam was built across the course of San Luis Creek, was originally at its confluence with San Luis Creek at approximately 250 ft (76 m). Today, Cottonwood Creek enters San Luis Reservoir, which raises the elevation of the creek's mouth to 548 ft (167 m), where it becomes Cottonwood Bay on the north side of the reservoir. The source of the creek is at Red Hill, a summit on the eastern slope of the Diablo Range.