The San Francisco Public Utilities Commission (SFPUC) has been working to develop short and long-term coastal protection measures and a management strategy that protects critical wastewater infrastructure and promotes environmental stewardship for chronic erosion problems at the south end of Ocean Beach. These short and long-term measures would be implemented as a two-phased approach.
Phase 1 (short-term) is a continuation of sand management activities conducted in cooperation with The National Park Service (NPS). Work initially began in early 2016, and the current year's work will begin in March, with an anticipated completion in May 2018. These efforts are a repeat of the successful short-term actions taken in past years in which excess sand in front of the O'Shaughnessy Seawall (north Ocean Beach) was transported to the erosion hotspot south of Sloat Boulevard (south Ocean Beach.)
In 2018, work will occur weekdays from 7am-4pm, and may extend until 5pm or weekends depending on progress. Southbound lanes of the Great Highway between Lincoln Way and Sloat Boulevard will be closed to traffic during work hours. Northbound lanes will be unaffected. South of Sloat Boulevard, single lanes in either direction will, at times, be closed. To protect public safety, access to the beach will be limited in certain areas when work is underway. Parking areas at the south end of the O'Shaughnessy Seawall, the Sloat parking Lot, and south of Sloat will be unavailable during construction.
The placement of excess sand at the south of Sloat Boulevard is an important action to protect the Lake Merced Transport Tunnel, a critical piece of infrastructure under the Great Highway that transports wastewater flows from the west side of the city to the Oceanside Wastewater Treatment Plant. Placing sand in this erosion hotspot also avoids the use of hard engineered structures such as rock revetments.
This year's project includes the following components:
1. Sand Backpass - Crews will excavate approximately 50,000 cubic yards of sand from north Ocean Beach and place it in erosion hot spots at south Ocean Beach, south of Sloat Boulevard.
2. Wind-Erosion Control Measures - Natural brush fencing, coarse sand, and/or other measures will be installed to reduce windblown sand from being transported onto the parking lots and the Great Highway south of Sloat Boulevard.
3. Sandbag Placement - To maintain public safety, we will also place approximately 700 sandbags in areas that have more defined, severe erosion south of Sloat Blvd.
Phase II (long-term; anticipated in 2021) would address public access, environmental protection and infrastructure needs in the context of erosion and climate-related sea level rise. The work would involve the implementation of coastal management strategies that include managed retreat, beach nourishment, and structural protection through adaptive management. The long-term plan proposes removal of existing coastal armoring and installation of a subsurface, low-profile structure that would protect vulnerable segments of critical wastewater infrastructure south of Sloat Boulevard. The design, environmental review, and permitting of Phase II are expected to take approximately 5 years to complete.
This project is part of an interim solution for the erosion issues at Ocean Beach. In support of a comprehensive solution to the erosion problem, the SFPUC and NPS actively participated in the development of the 2012 Ocean Beach Master Plan (OBMP). The OBMP, led by SPUR, was an interagency effort to develop a sustainable long-term vision for Ocean Beach, addressing public access, environmental protection and infrastructure needs in the context of erosion and climate-related sea level rise.
For more information on the Ocean Beach Master Plan, please visit: http://sf-planning.org/ocean-beach
NPS Project Manager - Trevor Rice