CARDIFF-BY-THE-SEA — On Monday, earthmovers began carting more than 25,000 cubic yards of sand out of the San Elijo Lagoon and onto the beach.
The process will reconnect the inlet of the lagoon with the ocean. In doing so, there will be better tidal circulation.
“If you let the inlet close, there’s no constant,” said Doug Gibson, a wetlands ecologist who is the executive director of the nonprofit San Elijo Lagoon Conservancy. “If you have a constant — the ocean — there’s better diversity and it keeps the lagoon in balance.”
Gibson explained that saltwater circulating into the lagoon prevents oxygen depletion, bolstering marine life.
The small inlet, intersecting Cardiff State Beach and the San Elijo campgrounds, is the lagoon’s only access point to the ocean.
Following winter storms, piles of sand block the inlet.
Throughout the weeklong excavation, earthmovers break through the sand berm. The earthmovers also remove sand underneath the bridge that overlooks the inlet, as well as sand just east of the bridge.
The sand that’s dredged is unloaded onto the nearby beach. Without the excavation, the inlet would likely be closed most of the year.
In the mid-90s, the San Elijo Lagoon Conservancy began experimenting with dredging.
After monitoring the effects, the conservancy determined spring is the best time to conduct excavations. If done in winter, powerful winter storms would likely reverse any dredgings in as little as a day. And as the temperature rises in the spring and summer, the excavation provides much-needed oxygen.
Gibson noted the excavation won’t affect grunions. It’s expected the grunions will be laying eggs next week, but the operation will be finished by then.
As of Tuesday morning, a precautionary advisory from the San Diego Department of Environmental health was in effect for swimmers and surfers at Cardiff State beach. Because sand is being dug up, the project has the potential to stir up pollutants.
While there might be periodic closures over the next week, the excavation will improve water quality for the rest of the year and beyond, according to Gibson.
The status of beaches’ water quality can be found at sdcoastkeeper.org.
For the past 12 years, excavations have been an annual event.
Gibson noted the dredgings have benefited the fish that depend on the lagoon as a nursery as well as other marine life and plants. Additionally, letting the lagoon breath cuts down on the mosquito population.
Gibson said the cost of the dredging operation is about $80,000.
Plus, monitoring the project throughout the year, which involves taking water samples and performing tests to gauge the health of the bird and fish populations, carries a cost of about $30,000.
The project is paid for with grants from the county and the conservancy’s endowment, which is funded by a variety of agencies and private donors.
“We’ll continue to see the lagoon get better,” Gibson said.