COAST CITIES — Work to place sand on area beaches was scheduled to resume Nov. 15, but in Carlsbad rather than Solana Beach, where an explosion that caused minor damage and no injuries suspended the project earlier this month.
One of the pipes delivering sand onshore became clogged Nov. 7. At about 4:30 p.m., workers from Great Lakes Dredge and Dock Company were attempting to clear the pipe by pressurizing it when a cap about the size of a manhole cover popped off and became a projectile.
The blast broke windows on a bulldozer and the lifeguard tower.
An investigation as to what caused the blast is ongoing but company officials said they won’t use that method should other pipes clog during the remainder of the project.
The Solana Beach pipe remains clogged and a leak was discovered in another pipe.
Colleen Windsor, SANDAG communications director, said Great Lakes officials told her pipes can become clogged but it’s very rare. When that’s occurred in the past, the same method was used to clear them but an explosion like the one in Solana Beach has never happened before.
Workers planned to restart the project in Carlsbad by placing about 140,000 cubic yards of new sand on the beach near the Palomar Airport Road and Carlsbad Boulevard intersection and extend it south roughly 2,200 feet.
Once that job is complete, work is scheduled to return to Solana Beach, sometime around Nov. 22. Fletcher Cove is slated to receive 144,000 cubic yards of sand. About 34,000 cubic yards had been placed prior to the blast.
Officials estimate it will take about three or four days to complete work in Solana Beach. The
project will then move back to Carlsbad, where it will conclude by adding 200,000 cubic yards of sand from Buena Vista Lagoon to the beach near Carlsbad Village Drive.
When completed, the 2012 Regional Beach and Sand Project will have placed 1.5 million cubic yards of quality sand on eight beaches from Oceanside to Imperial Beach.
Sand is dredged by the 315-foot Liberty Island from designated sites two miles offshore in water between 30 and 100 feet deep.
The borrow sites were researched and evaluated to ensure the sand would be clean and similar to the color, texture and size of grains currently on the beaches, according to the SANDAG website.
But slightly coarser sand is being used so it will remain on the beaches longer.
SANDAG partnered with the California Department of Boating and Waterways and the receiving cities for the $28.5 million project that began in Imperial Beach.
From Sept. 7 to Oct. 4, 450,000 cubic yards of sand was placed on 3,000 feet of beach in that city. The day after that portion of the project was complete, replenishment started in Oceanside, which received 292,000 cubic yards of sand on more than 4,100 feet of beach between Buccaneer Beach and just north of Hayes Street.
From Oct. 20 to Nov. 4, Moonlight, Cardiff and Batiquitos beaches received 287,000 cubic yards of sand. Work in Solana Beach started Nov. 4.
The state provided a grant that covered 85 percent of the project. Oceanside contributed $648,317. Carlsbad paid $809,559. The Encinitas portion was $819,352, and Solana Beach contributed $360,275.
A similar project was completed in San Diego by Great Lakes in 2001. Del Mar and the city of San Diego opted out of the program this year.
Sand naturally moves on and off the beaches depending on the time of year. According to SANDAG estimates, sand from the 2001 replenishment remained for about four to six years, although some appeared to be on the beaches in 2010.
Replenishment is necessary because development of roads and houses prevents sand that flows from the rivers from making it to the beaches.
Development along the coastline, which often includes sea walls and other bluff retention devices to protect those properties, also stops the natural erosion that creates and maintains beaches.
Sand replenishment restores and maintains beaches, which are essential for recreation and tourism and all the economic benefits associated with those activities.
Sand replenishment is common throughout the country and has occurred in several areas in the state, including Humboldt Beach near Eureka, Santa Clara, Santa Monica, Santa Barbara and Newport Beach beginning in the 1930s.