Emergency repairs are being done to tide gates, which might have played a role in the indefinite closure of a section of Moss Landing Road in California after a section of the roadways underbelly collapsed last week.
The east-west segment of the road that separates Moss Landing Harbor from the Moro Cojo Slough was shut down indefinitely by Monterey County Public Works as a precaution when rock and soil around one of three side-by-side culverts running under the roadway collapsed.
According to an Emergency Coastal Development Permit issued on Nov. 18 by the California Coastal Commission, corrosion on two of the three flap gates on the four-foot pipes allowed saltwater into the Moro Cojo Slough. Flap gates are designed to remain open during low tide when ocean water is not passing through the culverts, and then close from the pressure against them during high tide to prevent saltwater from entering the slough. But the old, corroded gates on two of the pipes would no long seat true, and saltwater began flowing into the slough, causing elevated salt levels in drinking and irrigation water on the east side of Highway 1, according to the Coastal Commission.
The county knew about this problem previously however, because there was a memorandum from Oct. 30 stating that there were plans to weld stainless steel patches to the corroded areas on the flaps within the next 30 days. Robert Murdoch, the director of the county Public Works department, said on Friday that crews will be going out this weekend to ascertain the extent of the erosion.