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Annual Inlet Excavation
Reconnecting San Elijo Lagoon with the Pacific Ocean
Because of North County's transportation corridors across the lagoon, one small opening, just south of San Elijo State Beach Campground, is the lagoon's only access to the Pacific Ocean. Keeping the inlet open to the ocean is critical to maintaining the health of San Elijo Lagoon.
THE WAY IT WAS
When early settlers arrived, only beach and dunes separated the lagoon from the ocean. The inlet was open most of the year, sometimes closing during the late summer, but opening again with the combined force of winter rains and surf. The inlet migrated between north and south according to the prevailing forces of the season.
A MODIFIED LAGOON
It has been decades since San Elijo Lagoon was naturally connected to the Pacific Ocean. Human modifications to hydrology occurred at a rapid pace after the 1880s. The first bridge and berm crossing the lagoon was constructed by the railroad in 1887, followed by Pacific Coast Highway in 1891 and, in 1965, Interstate 5, which divided the wetland in half.
This "partitioning" of the lagoon created altered flows for both fresh and saltwater, leading to accelerated sediment deposition, dramatically-reduced water quality, and a reduction in native estuarine habitats due to increased runoff from development upstream. During the winter storm cycles the inlet often became blocked by an accumulation of sand in the tidal channel. As temperatures rose in the spring, the demand for oxygen increased, and, without the circulation provided by the ebb and flow of the tides, the entire lagoon became stagnant, smelly and mosquito-ridden. The lagoon inlet, rarely, if ever, opens naturally.
WHY WE EXCAVATE
In 2001, a long-term financial endowment was established for the Conservancy to actively fund maintenance of tidal flushing. Efforts to keep the lagoon open to tidal circulation have shown that significant ecological benefits result from increased tidal flushing, as evidenced by:
But, left unattended, the inlet could again close from buildup of sand transported by high incoming tides, surf, and storm surges.
WORK IS UNDER WAY
Inlet Photomonitoring Slideshow
Improved Tidal Circulation is Funded By:
County of San Diego Department of Environmental Health: