City and experts afraid Ocean Beach will erode to highway, damage structures

Boulders lie on the sand at Ocean Beach in San Francisco, Calif. Engineers are attempting to shore up the beach with boulders in an attempt to prevent any further erosion. | staff photographer Edward Chow

On any given day, upwards of 50 people wander the shores of Ocean Beach, enjoying the scenery. But if erosion continues at its current rate, these views may drastically change.

This natural destruction of the beach and cliff areas is causing complications in use of the shoreline.

Among those complications is the Oceanside Wastewater Treatment Plant, located about 530 feet away from the shores of the Pacific Ocean. Heavy storms have become a concern because they are boring away at whatever land is left between the two.

When originally built in 1993, the plant was made to facilitate up to 65 million gallons of waste water, and it now seems that because of erosion, some of that waste water is spilling into the Pacific Ocean before it can be treated.

Frequent visitors to the beach have also noticed changes in the amount of space the beach itself has to offer.

Glen Park resident Alma Avila, 48, has lived in the area all her life and, as she watched her son play in the water, she said she has noticed a change when it comes to the reducing size of the beach.

“When I was younger the whole area was open,” Avila said. “But it’s probably the ebb and flow of the earth.”

Nearby roads have also been affected.

According to reports by Moffatt and Nichol, an engineering and infrastructure advising firm with offices in Walnut Creek, the cliffs of the Great Highway have drastically changed since July 2007. The ocean has eroded the beaches more than 50 feet into the highway, destroying parts of the southbound lane.

Of the more than 3,000 feet of highway south of Sloat Avenue, about 1,000 feet is protected with engineered structures, according to Dilip Trivedi, coastal engineer at Moffatt and Nichol.

“The places not protected would be at risk to erode,” he said.

Surfers have also noticed the erosion of Ocean Beach.

Mark Hartman, 41, has been surfing the area for more than 10 years. “I’ve seen the faces of the waves go as high as 35 feet tall,” Hartman said while suiting up for his weekly surf excursion. “Those rainy day waves can really cause some damage, but I don’t see why the erosion would stop.”

While they may be unable to stop the erosion, several groups are working to slow the process and ease the pressure it causes on certain structures.

Manager of capital planning for the Department of Public Works, Frank Filice has been working on erosion issues at Ocean Beach since 1996. Since then, he has coordinated many other organizations assisting in keeping the shorelines from toppling the highway once again.

“We’ve placed strategic barriers on parts of the highway,” Filice said. “Our focus as of late has been the northern parking lot, at the (23 Monterey) bus turnaround and down relocating the southbound roadways further back.”

Protecting these focal spots involves using either boulders or large piles of sand, depending on the urgency and time restraint of the situation and one restriction. “We’re only able to place the sand where the parks and recreations department allows us to,” Filice said. “We’ve taken some sand from the promenade area between Noriega and Santiago streets that went to the area by the water treatment plant.”

He said that they go where the parks and recreation department say to go because the need for sand is greater than the supply available.

“Sand management is strategic,” he said.

When it comes to placement of these sand banks, time cannot be an issue. In emergency situations, boulders are placed in lieu of sand. Filice expressed concern for the desire of sand usage, stating that it’s both aesthetically pleasing as well as an easy access point for citizens to reach the shore.

Even with sand banks, during the windy months of spring, Filice said that sand can be gusted upward and cause a hazard on the highway, which causes periodic closures for maintenance.

“Over the course of a year, the elevation could fluctuate at a rate of five to six feet dependent on the tides,” Filice said. “We want our long term results to prevent us from being an emergency response group.”

There are a few specific spots that have yet to be addressed, according to Filice, but they are waiting for the approval of the city.

“These El Nino storm types are the ones that cause the biggest threats,” he said. “We want to get things in place before the next one comes while trying to abide by the beach nourishment program set for passive protection of the beach. It’s an educational process for everyone who holds a stake in the area.”

Despite the ongoing efforts to conserve Ocean Beach, nothing seems to deter people from coming.

Avila comes down to the beaches at least once a month, and more if the weather permits. She understands that the misplaced boulders and chunks of fallen highway may help with the stabilization of the Ocean Beach master plan.

Filice compares the master plan for protecting against erosion to rock-crushing waters themselves: “Nothing is static. It’s always dynamic.”

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