Nearly 100,000 Tons of Sand Will be Moved for Interim Protection and Improved Beach Access

The SFPUC and the National Park Service (NPS), will begin sand management activities at Ocean Beach this month to address coastal erosion issues on the City’s westside. The initiative will begin this month and conclude by January 2020.

As part of the project, the SFPUC is pursuing both short and long-term improvements along Ocean Beach south of Sloat Boulevard to address climate change induced coastal erosion. These immediate upgrades are designed to protect wastewater infrastructure and improve beach access while longer-term improvements are being developed.

Ocean Beach Erosion Control: Bulldozers, backhoes and dump trucks will dig up and ferry 75,000 tons of sand south from the beach’s northern shores in an effort to temporarily replenish precious coastline lost to the forces of nature and accelerated by the effect of climate change. It’s a short-term measure the city has undertaken periodically since the early 2000s to combat and adapt to chronic coastal erosion at Ocean Beach south of Sloat Boulevard, where the shoreline’s attrition poses a mounting threat to critical wastewater infrastructure, natural habitats and beach access. Erosion at Ocean Beach poses a significant risk to the Lake Merced Tunnel, a stretch of mostly underground pipeline that runs parallel with the shore, carrying wastewater and storm runoff to the treatment plant. The tunnel is also used to store wastewater during large storms.

This project is a repeat of the successful management actions taken in 2012, 2014, 2016 and 2018, in which excess sand in front of the O’Shaughnessy Seawall (in north Ocean Beach) was transported to the erosion hotspot south of Sloat Boulevard (south Ocean Beach.)

The beach at the northern end of Ocean Beach has been widening and accumulating sand while the area south of Sloat Boulevard has experienced a loss of beach and is eroding. The accumulation of sand impedes visitor beach access by filling in the seawall’s stairwells and promenade and increases sand maintenance efforts and costs for the NPS and the City.

The placement of excess sand at the south of Sloat Boulevard has been an important action to address climate change and to protect the Lake Merced Transport Tunnel, a critical piece of infrastructure that transports wastewater flows from the west side of the city to the Oceanside Wastewater Treatment Plant. Placing sand in this erosion hotspot is environmentally friendly and helps to avoid placement of hard engineered structures such as rock revetments.

This year’s project includes the following components:

  • Sand Backpass: Crews will excavate about 65,000 cubic yards of loose sand along the O’Shaughnessy Seawall at the northern reach of Ocean Beach and transport it to Ocean Beach south of Sloat Boulevard. That is the equivalent of moving 97,500 tons of sand.
  • Sandbags: Crews will complete maintenance of existing sandbag structures and place approximately 28 new sandbags. The sandbags are currently stored at the SF Zoo’s leased property.
  • Beach Debris: Crews will remove and dispose of hazardous beach debris.

What to expect:

  • Southbound traffic on the Great Highway will be detoured to Sunset Boulevard between Lincoln Way and Sloat Boulevard.
  • Northbound traffic will experience a lane reduction between Highway 35 and Sloat Boulevard. Muni bus stops in the same (northbound) stretch will not be affected.
  • Beach access will be limited in certain areas when work is underway to protect public safety.
  • Parking areas at the south end of the O’Shaughnessy Seawall and the overlook parking areas south of Sloat Boulevard will not be available during construction.
Ocean Beach Erosion Control: Bulldozers, backhoes and dump trucks will dig up and ferry 75,000 tons of sand south from the beach’s northern shores in an effort to temporarily replenish precious coastline lost to the forces of nature and accelerated by the effect of climate change. It’s a short-term measure the city has undertaken periodically since the early 2000s to combat and adapt to chronic coastal erosion at Ocean Beach south of Sloat Boulevard, where the shoreline’s attrition poses a mounting threat to critical wastewater infrastructure, natural habitats and beach access. Erosion at Ocean Beach poses a significant risk to the Lake Merced Tunnel, a stretch of mostly underground pipeline that runs parallel with the shore, carrying wastewater and storm runoff to the treatment plant. The tunnel is also used to store wastewater during large storms.
Ocean Beach Erosion Control: Bulldozers, backhoes and dump trucks will dig up and ferry 75,000 tons of sand south from the beach’s northern shores in an effort to temporarily replenish precious coastline lost to the forces of nature and accelerated by the effect of climate change. It’s a short-term measure the city has undertaken periodically since the early 2000s to combat and adapt to chronic coastal erosion at Ocean Beach south of Sloat Boulevard, where the shoreline’s attrition poses a mounting threat to critical wastewater infrastructure, natural habitats and beach access. Erosion at Ocean Beach poses a significant risk to the Lake Merced Tunnel, a stretch of mostly underground pipeline that runs parallel with the shore, carrying wastewater and storm runoff to the treatment plant. The tunnel is also used to store wastewater during large storms.

In partnership with the California Coastal Commission and the NPS, the SFPUC monitors beach erosion and only takes action on an as-needed basis.

After this work is complete, San Francisco Public Works will implement additional measures in this same area to improve stormwater management which is contributing to coastal erosion.

Related Projects in the Area:

To reduce Ocean Beach erosion and improve stormwater management, the construction of the Public Works Great Highway Localized Drainage Improvements Project is expected to begin after the SFPUC project ends and last for approximately six weeks. The project will overlay asphalt over a portion of the existing southbound lane of the Great Highway south of Sloat Boulevard to redirect surface water runoff toward the median of the road, remove existing asphalt concrete from the median area, and improve local stormwater drainage. Pedestrian and vehicular access may be limited in the area.

Sand removal, loading from Ocean Beach to fill cliff in front of Oceanside Treatment Plant, to keep landside from eroding into the ocean.