DEL MAR — If all goes as planned, the last of the heavy equipment in the San Dieguito wetlands should be removed by spring and the $86 million restoration project will be complete except for long-term beach monitoring and ongoing maintenance such as planting, weeding and erosion control.
Construction, which was expected to take about three years, began in 2007. Since then the project team has created 162 acres of new coastal wetlands in the San Dieguito River Valley. The goal was to restore 150 acres.
Berms have been built to protect those wetlands and direct sand to the beach. A power line was relocated, drainage was added and an access path to North Beach was installed.
The Grand Avenue Bridge was converted to a scenic overlook and four least tern nesting sites have been created. While the birds have not yet nested in those areas, decoys have been placed on the sites to attract them and the terns are foraging there, David Kay, from Southern California Edison, said during an Aug. 16 update at Solana Beach City Hall.
The three remaining major elements that will be completed within the next nine months are armoring the river bend east of the bridge on Jimmy Durante Boulevard, dredging sand from the inlet channel and reconfiguring the tidal inlet at the Coast Highway Bridge.
Kay said plans to armor the river bend, which will protect San Dieguito Drive, include removing the existing “helter-skelter” riprap made of steel and railroad ties and replacing it with engineered riprap.
Jacqueline Winterer, president of the Friends of the San Dieguito River Valley, said the existing riprap should not be destroyed. She said the area used to be a landing dock for barges and the materials are likely important artifacts.
“It’s actually very significant,” Winterer said.
The channel dredging, which should start this winter, will begin east of the bridge on Jimmy Durante and proceed toward the beach. Some of the 65,000 yards of sand will be transported to disposal areas east of Interstate 5. The rest will be placed on the beach, mostly south of the inlet.
The tidal inlet will be reconfigured beginning in February or March. Sand will be removed east of the bridge on Coast Highway 101 and a sand trap will be sculpted into the river bottom.
The existing channel will be filled with sand and the inlet channel will be relocated further north. About every 18 months, the channel is expected to close naturally, so it will be relocated each time. The sand trap will also be dredged periodically when it fills with sand.
As the project team completes the restoration, the San Dieguito River Park Joint Powers Authority is working to finish the coastal sections of the Coast to Crest Trail, a 55-mile multiuse path from Volcan Mountain in Julian to the beach in Del Mar.
“The trail system was put in to bring the public in, but if it’s put in wrong, it can hurt the project,” Executive Director Dick Bobertz said. “It’s close enough for people to appreciate the habitat, but not so close that it affects it.”
Bobertz said most of the work on the trail east of I-5 is going as planned. It’s the “reach-the-beach” segment that is causing problems.
“This is the one we haven’t figured out yet,” he said. “We have funding to figure it out, and we’re going to study the heck out of it. But several constraints are prohibiting the extension.”
Bobertz said he is open to any and all ideas. He also described the restoration as “a project of a lifetime for anyone involved in environmental projects.”
“What an incredible attribute to turn over to a community,” he said.
The wetland restoration is funded and managed by Southern California Edison to offset the negative impacts of the San Onofre Nuclear Generating Station.
Quarterly beach monitoring at seven stations is required. The project must meet performance standards for the operating life of San Onofre, which is currently 40 years. Kay said the monitoring frequency could be reduced if negative impacts are not found.
Kay said completing the restoration is somewhat bittersweet. “The team has had so much fun on this project,” he said. “It’s the best-kept secret at Edison.”