DEL MAR — Restoration of the San Dieguito Wetlands is now in the final phase of construction. The five-month project, which began Feb. 15, will dredge approximately 85,000 cubic yards of sand currently clogging the San Dieguito River channel, resulting in a better exchange of water from the ocean to the new nature preserve.
Clearing the channel of sand on the east and west sides of Jimmy Durante Bridge will allow an estimated 80 million gallons of water to reach the newly created wetlands during daily tides to make the ecosystem naturally sustainable to support native vegetation and increasing fish and bird populations.
The $86 million restoration project, which began in 2007, is being conducted by Southern California Edison and San Diego Gas & Electric to offset the impacts of the San Onofre Nuclear Generating Station.
“The site has already become a nursery for more marine life than the relatively small number of fish impacted by the ocean-water cooling system of our San Onofre Nuclear Generating Station,” said David Kay, Southern California Edison manager of environmental projects.
The specialized dredge operating in the sensitive wetlands east of Jimmy Durante Bridge is small, has minimum emissions and makes very little noise.
Sand is being pumped to a stockpile area, where it is then dried for placement on five California least tern nesting sites and other upland areas east of Interstate 5. Once the upland areas have received the sand from the river bottom, they will be covered with top soil and planted with native habitat.
Excavators and front-end loaders will be used to remove sand in the channel west of Jimmy Durante Bridge. The same process of sand removal and placement has been used in past years to open the river mouth.
The sand in this area is considered high quality and will be used to replenish Del Mar beaches.
“The project has become a real natural asset for San Diego and is a living laboratory for studying how nature can adopt manmade ecosystems,” said Pamela Fair, vice president of environmental, safety and support services.
“The ongoing research is helping our scientists understand how fish and birds colonize and re-populate previously disturbed areas to benefit other restoration projects around the country,” she said.