Laguna–San Diego Coastal water resource basin (HUC 180703) is one of three hydrologic basins within the Southern California Coastal water resource subregion and is one of approximately 2,200 water resource basins in the United States hydrologic unit system.
The Laguna–San Diego Coastal water resource basin is a third-level subdivision of the United States hydrologic unit system. The tiers of the classification system, in order from largest to smallest, are regions, subregions, basins (formerly accounting units), subbasins (formerly cataloging units), watersheds, and subwatersheds. These geographic areas contain either the drainage area of a major river, or the combined drainage areas of a group of rivers.
The Laguna–San Diego Coastal basin is approximately and includes the drainage into the Pacific Ocean from Moro Canyon near Laguna Beach to the international border between the United States and Mexico. The Laguna–San Diego Coastal basin is composed of five fourth-level hydrological units called water resource subbasins (formerly known as water resource cataloging units), each with its own 8-digit hydrologic unit code.
List of subbasins of the Laguna–San Diego Coastal basin Basin HUC Basin nameBasin descriptionBasin locationBasin sizeBasin map18070301Aliso–San Onofre subbasin San Juan Creek, Aliso Creek, Laguna Beach coastal streams, Dana Point coastal streams, San Clemente coastal streamsOrange County18070302Santa Margarita subbasinSanta Margarita River, drains Fallbrook and Marine Corps Base Camp PendletonSan Diego County, Riverside18070303San Luis Rey–Escondido subbasinSometimes called the San Luis–Carlsbad Watershed; includes San Luis Rey River, Escondido Creek, Buena Vista Lagoon, Agua Hedionda Lagoon, Batiquitos Lagoon, San Elijo Lagoon, Loma Alta Creek and the associated sloughSan Diego County18070304San Diego subbasinSan Dieguito Creek, Peñasquitos Creek, San Diego River, Pueblo Watershed coastal streams including Chollas Creek, Sweetwater River and reservoirs, Otay RiverSan Diego County18070305Cottonwood–Tijuana subbasinTijuana River (international watershed, subbasin boundary is at the border)San Diego County
See also South Coast hydrologic region Groundwater recharge Water in California Principal aquifers of California
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