The U.S. Army Corps of Engineers is recommending that the middle section of the Port San Luis breakwater be repaired at a cost of $2.8 million.
A report by the Corps finds that wave action and possibly the 2003 San Simeon Earthquake have caused a portion of the breakwater to fall apart. The damage was discovered in November 2009 when the Corps did sonar and laser scans of the structure.
“The breakwater has a service life approaching 100 years and has experienced damage to its head and trunk sections in the form of displaced and ejected armor stones and loss of armor stone interlocking,” the report concluded.
The head of the breakwater near Avila Beach was repaired in 2005, and the middle section requires similar repairs. These will consist of adding more rocks to the structure and using a floating crane to stack the rocks in an interlocking fashion.
The Port San Luis Harbor Commission will receive and discuss the report when it meets this evening, said Steve McGrath, the harbor manager. The commission is not expected to take any action.
Congress will have to allocate funds for the repairs in an upcoming budget, probably in 2012. Sen. Dianne Feinstein has submitted an appropriations request for $3.4 million, McGrath said.
Completed in 1913, the breakwater is an integral part of the harbor’s infrastructure. It projects 2,401 feet from Point San Luis and protects the harbor’s piers, moorings and other facilities from westerly storm waves.
The breakwater consists of a line of large, interlocking boulders that rise 13 feet above low tide. It includes a naturally occurring rock called Whalers Island. Areas of the structure that do not reach the 13-foot height should be rebuilt, report says.
The report does not address the question of sea level rise as a result of climate change, McGrath said. Climate scientists are predicting that sea levels will rise 4 feet or more along the San Luis Obispo County coastline by 2100.
“If an increase in height of the overall breakwater is recommended as a result of such consideration, it seems prudent to incorporate that at this time, even if just to this repair section,” McGrath wrote in a letter to the Corps.
Reach David Sneed at 781-7930.