A man shovels up oil on a section of Refugio State Beach in California after a 2015 spill [File: Kenneth Song/The News-Press via AP]

Los Angeles, October 4 (RHC)-- A large oil spill off the California coast began washing ashore at Huntington Beach over the weekend after an oil rig pipeline was breached, leaving dead fish and birds strewn on the sand, local and federal officials said.

An estimated 570,000 litres (126,000 gallons) spread into an oil slick covering about 30 square kilometres (13 square miles) of the Pacific Ocean since it was first reported on Saturday, according to Katrina Foley, the Orange County supervisor.

“The impact to the environment is irreversible,” she said in a statement.  She said the spill was caused by a breach connected to the Elly oil rig and stretched from the Huntington Beach Pier down to Newport Beach, a stretch of coast south of Los Angeles that is popular with surfers and sunbathers.

On Sunday, Foley said the oil had infiltrated the Talbert Marsh, a large ecological reserve, causing “significant damage."   A petroleum stench permeated the air throughout the area.  “You get the taste in the mouth just from the vapors in the air,” she said.

Beaches were closed to swimming and a local air show was cancelled, although some people were undeterred from setting up chairs on the beach to enjoy a sunny Sunday or strolling along the pier.

Huntington Beach officials said they had deployed booms to prevent oil flowing into the Bolsa Chica Ecological Reserve and the Huntington Beach Wetlands.  The U.S. Coast Guard, working with local and state agencies, flew planes to assess the spill and had hired contractors to clean it up.

Officials said they were investigating the cause of the spill and the type of oil involved.