Ocean Beach sand plan could help curb erosion south of Sloat
A joint project of the National Park Service and the city of San Francisco plans to truck sand from the north end of Ocean Beach and dump it south of Sloat Boulevard, starting in just a few weeks.
The prosaic name of the Ocean Beach Sand Maintenance Project masks the ambitious aim of the collaboration, which is to study whether the erosion that has chewed up the southern end of Ocean Beach can be effectively countered not by seawalls and piles of rocks, but by a simple and abundant resource: sand.
The Ocean Beach Sand Maintenance Project would remove about 100,000 cubic yards of sand from the north end of Ocean Beach. That’s enough to fill the beds of roughly 62,000 Ford F150 pickup trucks.
Dump trucks would take the sand south down the Great Highway, depositing the majority of it in an area extending slightly to the north and south of the parking lot at the end of Sloat Boulevard. Large parts of that parking lot have simply fallen onto the beach because of past erosion, and access to the water is difficult and sometimes dangerous.
A much smaller portion would be placed farther south, just to the north of the west gate of the Oceanside Water Pollution Control Plant. Parts of this area eroded so rapidly in the winter of 2010 that the City closed the Great Highway south of Sloat Boulevard for months, and installed a large field of boulders to prevent the ocean from claiming the road and wastewater pipes that run underneath it.
The Sand Maintenance Project is hoped to serve three purposes, officials from the City and the NPS explained at a Tuesday meeting at the United Irish Cultural center.
The first purpose would be to remove sand from where there’s so much of it that it’s creating maintenance problems.
So much sand has accumulated on the north end of the beach that for weeks this spring it buried the O’Shaughnessy seawall, the adjacent sidewalk, public garbage cans, coin-operated binoculars, landscaping, parts of parking lots, portions of the Great Highway and even sections of outer Balboa Street. But simply shoveling the sand back over the wall toward the ocean only creates a ramp to launch windblown sand eastward over the wall again, so the Sand Maintenance Project would “mine” and remove that sand from a strip of the beach west of the seawall, from about Stairwell 1 at the base of the hill leading up to the Cliff House, to about Stairwell 21 a little south of the Beach Chalet.
The second purpose would be to protect vulnerable shoreline areas from the direct impact of waves and storm surges. Officials say they don’t expect the sand to stay put for more than a year or perhaps two, but it should keep the water away from cliffs and bluffs while it lasts.
Third, and perhaps most importantly, the proposed Ocean Beach Sand Maintenance Project would provide a test case to study whether an even larger “beach nourishment” project could protect this part of the beach for years into the future. That’s because planners including those from the federal government, the City, and SPUR, the organization that recently completed the far-reaching Ocean Beach Master Plan, have been looking into whether it would be feasible to build up south Ocean Beach with three times as much sand as the Sand Maintenance Project proposes to move.
That sand wouldn’t come from Ocean Beach itself, but from the San Francisco Bar, a large underwater sand bar that continually builds up west of the mouth of San Francisco Bay. The San Francisco Bar builds up so high that it would block easy access to the bay for large ships — if the U.S. Army Corps of Engineers did not dredge a channel in it every year. The sand that’s taken from the San Francisco Bar is dumped offshore of south Ocean Beach, but it doesn’t seem to be accumulating on the beach, so federal officials are looking into acquiring equipment that would allow the sand to be pumped right onto the shore.
The NPS and the SFPUC said they intend to move swiftly once they get permits and environmental approvals for the project, and could start in late July or early August.
Once the project starts, it would last about five weeks and would involve some temporary but significant impacts on traffic and parking near Ocean Beach. The southbound lanes of the Great Highway from Lincoln Boulevard to Skyline Boulevard would be closed from 7 a.m. to 8 p.m. on weekdays while work is underway, to allow trucks and other equipment to travel between the mining and placement sites.
Documents obtained by the Ocean Beach Bulletin show that the City expects only about 20 parking spaces would be used by the project at the north end of the beach, where 600 spaces are available. But parking also would be affected at the Sloat Boulevard parking lot.
Although it’s not directly addressed in the project description the SFPUC gave the Planning Department, officials at Tuesday’s meeting indicated that the parking lot on the west side of the Great Highway near the Oceanside water plant would be affected as well. And closing the southbound lanes of the Great Highway would eliminate public access to that parking lot during working hours.
View the presentation slides from the Ocean Beach Sand Maintenance Project public meeting: