The Batiquitos Lagoon is a coastal wetland and estuary located between southern Carlsbad and Encinitas, in the North County region of San Diego County, California. The lagoon itself consists of 610 acres with a drainage basin of about 55,000 acres. Its primary freshwater tributaries being San Marcos Creek from the east and Encinitas Creek which flows north along Green Valley, entering the lagoon under El Camino Real and La Costa Avenue, respectively. It is one of the few remaining tidal wetlands on the southern California coast.
Part of the lagoon is designated as the Batiquitos Lagoon State Marine Conservation Area, run by the California Department of Fish and Game as a nature reserve.