A one-time Coast Guard cutter was sunk off Mission Beach on Tuesday to help establish an artificial reef.
The Ruby E, a 165-foot ship built in 1934 and decommissioned in 1965, was the fourth vessel to be sunk in the artificial reef complex about 1 1/2 miles outside Mission Bay, said Al Bruton, a diver who is helping coordinate the project.
The artificial reef duplicates conditions of natural reefs by providing a habitat for sea life to breed and develop, Bruton said.
The program, which began in 1987, is a cooperative effort between the Department of Fish and Game and the San Diego Council of Divers. The Ruby E was donated by San Diego Tug & Barge, a private salvage company.