Tuesday, January 26, 2010

Ocean Beach Erosion - Emergency Plans Controversy

The San Francisco Zoo is literally at the centre of a controversy on coastal erosion: whether to slow down the erosion with sand, close part of the Great Highway and possibly re-route traffic around the zoo, or shore up the receding coastline with rocks and keep the highway open.

Also at risk is a massive 10 million gallon wastewater tunnel under the highway that is only feet away from the erosion.

The area was declared an emergency zone a week ago as over 30 ft of coastline at Ocean Beach has eroded in the winter storms, and 70 ft since 2007.

Last night the Ocean Beach Vision Council, responsible for developing a long-term strategy for the beach, held a town hall meeting with local interest groups and residents in the Park Chalet at the end of the Golden Gate Park to debate the issue with the Department of Public Works.

At the heart of the contention are DPW plans to place a protective barrier of large rocks along the beach, in a process known as 'armoring,' and to re-open the road. Project Manager, Frank Filice, who outlined the plans, was opposed by residents, environmentalists and engineers who argued that armoring accelerates the erosion process, hinders surfing and swimming, and access to the beach.

Today the DPW are seeking support from the city's Board of Supervisors to ratify the emergency declaration and allow the armoring to go ahead.

The emergency area now covers 900 ft of bluff, running from Sloat Boulevard past the zoo and the Oceanside Wastewater Treatment Plant.

With El Nino conditions and the recent winter storms, the coastline has not only been eroded by 70 ft in places since 2007 - but has also in part worn away under the Great Highway - the coastal road that runs the length of  California - and is endangering the Lake Merced Wastewater Tunnel, a 14 ft-wide, 10 million gallon facility that serves Daly City.

Efforts to slow the effects of erosion along the coastline have been underway for the last 15 years.

Coastal Engineer, Bob Battalio, and Dean LaTourrette, executive director of Save the Waves Coalition, an organization that works for the preservation of surf spots around the world, and who is also a local resident, both opposed armoring.

Instead, they want to see sand placed on the beach, the highway moved inland and reduced to two lanes with no median, and natural erosion allowed over time to take its course. An alternative, said Bob Battalio, in response to a question from the audience, is to re-route traffic around the zoo.

This 'managed retreat' was proposed by the original Ocean Beach Task Force that met between 1999 and 2003, and Bob Battalio called on the DPW to revert to its findings.

Dean LaTourrette said surfing would be adversely affected by armoring, and there were several surfers on his staff who lived and surfed at Ocean Beach. Furthermore, the DPW had not taken sea rise into consideration, he said. He urged the DPW not to 'try to reinvent the wheel.'

Frank Filice presented the results of the DPW consultations, showing the three options the department had considered: to erect a sand barrier, costing $14 million; an armor stone revetment for $2,578,000; or sand-filled super sacks for $2,564,000.

Closure of the southbound road is affecting 11,660 vehicles daily, according to a 2002 study, he said. Also affected by erosion is the rock crown of a treated wastewater outfall pipe four miles off shore.

The DPW hope to work towards protecting the top of the bluff this year. In the long term, 2010 - 2015, they plan to work with the Army Corps of Engineers, the National Park Service, and other local, state and federal agencies. Plans include rebuilding the beach, protecting the bluff and public infrastructure, and road improvement.

They also aim to 'make every practical effort to preserve and protect wildlife habitats and the natural beauty of Ocean Beach and the surrounding area.'

About 150 people attended the meeting that was convened by Lara Trupellli - pic above - chair of the Ocean Beach Vision Council.

No comments: