San Dieguito Lagooon heading back to its natural state
Jonathan Horn
Sign On San Diego
03/20/2011
DEL MAR — After five years of deconstruction, a project to bring 150 acres of Del Mar wetlands back to their natural state is all but complete.
The project, funded by SoCal Edison and SDG&E, is known as the San Dieguito Lagoon Restoration. It involves restoring the wetlands that begin on the north end of Del Mar and stretch east of Interstate 5 into San Diego. Part of the area was once paved with an airstrip used by the Navy and later by celebrities to fly in for horse racing at the fairgrounds. The Grand Avenue Bridge, built in the early 1940s, had provided access to the airport. A portion of the bridge remains and now is used a viewing platform for the wetlands.
“We’re undeveloping the land, so to speak,” said David Kay, a manager of environmental projects for Southern California Edison, the lead agency on the project.
Over the next four months, a boat attached to a 1.3 mile pipe will dredge 85,000 cubic yards of sand from the San Dieguito River channel, which connects the ocean to the lagoon. The sand otherwise builds up and clogs the river, cutting off a vital source of nutrients for the lagoon wildlife. The dredging began in February. By removing the sand, tides can flow freely under the Jimmy Durante Boulevard bridge, east of the fairgrounds and into the heart of the lagoon. The ocean waters, filled with plankton and other nutrients, will feed plant life and fish that live there, restoring the ecosystem and maintaining the food chain.
Project spokeswoman Kelly Sarber said restoration workers counted 12 million baby fish in the lagoon seven months after it opened in 2008. She said there’s also been a tripling of the bird species. The project began in 2006.
“It’s exciting to see the resilience of nature and to see how it comes back in with full force,” she said.
The $90 million restoration is being paid for by Edison and San Diego Gas & Electric, which co-own the San Onofre Nuclear Generating Station. The Coastal Commission required the companies to restore 150 acres of tidal seawater wetlands to balance the damage to ocean life the plant, built in the 1970s, causes each year.
A study showed that in 2009 the plant sucked in 621 tons of small fish. Kay said that for comparison, the commercial sportfishing industry catches 60,000 tons of fish each year off the California coast.
The dredging boat will move the sand from the inlet to dry in settling ponds east of Interstate 5. It will then be used for either beach sand or to buffer nesting sites for the endangered California least tern. Once the dredging is completed, the inlet will allow about 160 million gallons of ocean water into the lagoon per day.
