Loma Alta Creek begins as rising springs just west of Melrose Drive in the City of Vista and flows to Loma Alta Slough (Slough). Loma Alta Creek flows parallel to Oceanside Boulevard and the Slough is located north of Buccaneer Beach Park. Loma Alta Creek is just over seven miles long and drains nearly 6,300 acres of land. The Slough is a 107 acre coastal estuarine wetland. Loma Alta Watershed is the northernmost watershed in the Carlsbad Hydrologic Unit.
The only named tributary is Garrison Creek which parallels Mesa Drive west of El Camino Real. Much of the creek has been modified throughout the years, with the use of fully or partially concrete-lined channels to stabilize the creek-bed slopes.
Over 70 percent of the watershed is developed and is comprised of the following land uses: Residential (45 percent), industrial (7 percent), commercial (4 percent) and public facilities (16 percent). All of these land uses are potential sources of pollutants.
Most of the undeveloped land contains non-native habitat, with numerous exotic/invasive plant species. The remaining native vegetation includes freshwater marsh, willow riparian scrub, coastal sage scrub, chaparral, and valley and coastal grassland. Loma Alta Creek supports approximately 100 species of wildlife including threatened and endangered species.
The Slough has been found to have exceedances of indicator bacteria and is also impacted by eutrophication, or having too many nutrients in the water which contribute to the overproduction of algae.
Recreational Activities: Fishing, walking, biking, bird watching, picnicking.
Public Access: There is limited access to Loma Alta Creek. Loma Alta Slough is accessible fro Buccaneer Beach Park located on Pacific Street just north of Morse Street.