Ocean Beach, one of the gems of the San Francisco landscape, faces significant challenges. For the past two years, SPUR has led an extensive interagency and public process to develop the Ocean Beach Master Plan, a comprehensive vision to address sea level rise, protect infrastructure, restore coastal ecosystems and improve public access.
The Ocean Beach Master Plan and Implementation Studies are made possible by the State Coastal Conservancy, the San Francisco Public Utilities Commission and the National Park Service.
Benjamin Grant, Public Realm and Urban Design Program Manager, firstname.lastname@example.org
Recent data from the National Oceanic and Atmospheric Administration (NOAA) suggest that an El Niño phenomenon may develop in the Pacific Ocean this year. El Niño weather patterns — or properly El Niño Southern Oscillations — typically generate wetter and more frequent winter storms in California, with potential implications for erosion at Ocean Beach. What will these storms mean for the future of the beach, and for the recommendations in SPUR’s Ocean Beach Master Plan?
The El Niño pattern generally occurs every two to five years when surface temperatures rise in the central Pacific, driven by a reversal in the usually easterly trade winds. This results in greater precipitation in California — sometimes much greater, as in the winter of 1996-97, which saw more than 47 inches of rain in San Francisco and considerable erosion at Ocean Beach.
Since this spring, scientists have been warning that an El Niño — potentially a major one — looked likely. NOAA’s Climate Prediction Center has issued an “El Niño Watch.” From the standpoint of California’s record drought, many at first saw this as a ray of hope. But more recent estimates suggest a more modest El Niño, which may not be sufficient to increase rainfall in Northern California by much — but may still cause coastal erosion. Current estimates put the chances of an El Niño developing this winter at about 80 percent.
It’s been more than four years since a devastating series of winter storms caused severe erosion at the south end of Ocean Beach, in the winter of 2009-10. In some locations, bluffs receded 40 feet in a single season, threatening the Great Highway, coastal parking lots and underground sewer infrastructure. San Francisco responded by placing boulder revetments (embankments of stone riprap) on the beach, creating controversy among environmentalists, surfers and the California Coastal Commission. It wasn't the first time. The same pattern — an El Niño storm season, severe erosion and emergency coastal armoring — occurred in 1997.
In 2011, the Coastal Commission rejected a city permit application for both existing and additional armoring, demanding instead a long-term plan to address coastal hazards. SPUR was already at work on the Ocean Beach Master Plan, which took on a new urgency. Meanwhile, the city turned to softer, more adaptive measures, including the placement of sandbags and “backpassing” of large quantities of excess sand from the north end of Ocean Beach to the eroded sections at the south end.
The Ocean Beach Master Plan recommends closure of the Great Highway south of Sloat Boulevard for “managed retreat” (i.e., gradually removing manmade structures in the path of sea level rise) in the coming decades. The San Francisco Department of Public Works is planning to narrow the road to two lanes within a few years, and aggressive measures to prevent erosion are no longer the order of the day. SPUR and its consultants are working with the San Francisco Public Utilities Commission (SFPUC) and the Coastal Commission on a package of softer measures, including additional sand placement, sand bags and the consolidation of existing rubble into a smaller, erosion-resistant footprint. These steps are intended to get the beach through several storm seasons without the need for additional structures like revetments or sea walls, while longer-term measures are developed to implement the master plan vision.
Will the softer measures be adequate if an El Niño season produces a series of powerful storms? It’s difficult to say with certainty, but there are several reasons to be optimistic.
First, the responsible agencies are focused on protecting critical wastewater infrastructure, rather than the roadway or parking lots, meaning there is a greater tolerance for letting nature take its course.
Second, the existing revetments, though controversial, are in place and effectively protecting what had been the most vulnerable areas. In addition, the sandbags that were placed in 2011 have held up very well, providing coastal protection that is easily reversible, inoffensive and easily expanded.
Lastly, the city is in a much more proactive stance, proposing measures in advance of anticipated storms and preparing to act quickly if threats develop. In particular, the SFPUC is preparing to implement additional preventive sand placement and to fill and stockpile sandbags in advance of winter storms, for rapid deployment.
There are, of course, no guarantees. If this year’s El Niño produces severe and repeated storm surges, the environmental risk of a ruptured sewer could reach an unacceptable level, requiring emergency armoring. But for the first time, all actors are working together to make armoring the action of last resort and to prepare a more adaptive approach.
Thanks to all of you who stopped by our Open House at the County Fair Building last Saturday (05/10) and chose to spend the sunny morning with the Ocean Beach project teams!
For those who didn’t make it or want to refresh your memory, you can view the presentation boards below. The boards present information on the three different Ocean Beach implementation studies currently in progress, as well as a summary of the Ocean Beach Master Plan process and its Key Moves.
You can also view the animated video prepared by AECOM for the Open House, which displays the sequence of actions and coastal management measures at the South reach of Ocean Beach:
We received a lot of valuable comments and ideas from all of you who attended the Open House and we will post all of them online in the coming weeks. In case you weren’t able to attend our Open House and want to provide your feedback you can use the comment form from the Open House. You may either print it and mail it to us here at SPUR (654 Mission Street), or you can simply write your comments in an email to email@example.com until May 23rd.
Once again thank you all for your interest and participation!
One of the ways to capture public feedback during the Open House was through post-it notes on the presentation boards. Image by Patricia Fonseca (AECOM).
What: Open House on Ocean Beach Master Plan Implementation Projects
When: Saturday May 10, 9 a.m. to 12 p.m. (drop in for brief presentations noted below)
Where: County Fair Building in Golden Gate Park (near Lincoln Way and 9th Ave) map
Join SPUR, partner agencies, community leaders and consultant teams for an update on projects to implement the recommendations in the 2012 Ocean Beach Master Plan. The plan was developed through a two-year public and interagency process. It presents a series of recommendations to improve coastal access, restore ecological function, and protect critical infrastructure in the face of chronic erosion and sea level rise.
This open house will provide updates on three projects currently underway to carry those recommendations forward. The project teams will be on hand to discuss their work in progress and get your ideas and feedback. Stop by any time from 9am-12pm. Brief optional presentations will provide some background on each project.
1) Coastal Management Framework (9:30 am)
2) Transportation Study (10:30 am)
3) Open Space Design Study (11:30 am)
Each of these will result in proposed projects that are ready for environmental review, permitting, and implementation on the ground over a period of several decades. New trails, a cleaner beach, restored dunes and bluffs, and safer roadways are all being explored, all while protecting public investments in clean coastal waters.
As sea levels rise, big changes are inevitable, but we can work with the changes to make better places for everyone. This award-winning effort is on the cutting edge of adaptive coastal planning.
SPUR, along with agency partners and design consultants from AECOM, has begun work on an Open Space Design for recreational and landscape improvements on Ocean Beach and surrounding streets and trails. Initial efforts will focus on the parking area and bluffs south of Sloat Boulevard. The Open Space Design is an adaptive plan that follows the natural progression of the beach and bluffs. With different parts of the beach eroding at varying speeds, the design team is exploring creative ways to adapt to coastal changes. The design is driven by the guiding principle of managed retreat on the South part of the Great Highway that will allow for dune and bluff restoration as recommended by the OBMP. Near-term open space and access improvements will become possible thanks to the Department of Public Works (DPW) plans for narrowing the Great Highway and to funding granted from Coastal Conservancy. These changes will make Ocean Beach a much better public space for all to enjoy.
The immediate coastal protection plan that covers the next three storm seasons will offer some exciting landscape opportunities in the very near future, with improvements to access and beach aesthetics. The transient nature of the landscape poses many design challenges but also creates opportunities to celebrate this temporary environment, for instance through public art elements. The interim reconfiguration of the Great Highway South of Sloat creates recreational opportunities, which could include a temporary pedestrian and bike trail, in the vacated southbound lanes and parking areas. It also allows for the removal of excess asphalt, beach cleanup and re-vegetation. Brushwood and other natural materials will minimize effects of windblown sand and greatly improve beach aesthetics while channeling pedestrian access in a way that won’t compromise the beach.
The interim Open Space Design will be a precursor of the long-term vision. A network of interconnected pedestrian and bike trails will link Ocean Beach smoothly to Fort Funston, San Francisco Zoo, Lake Merced and Golden Gate Park, as well as the existing dune and Lower Great Highway trails. The Fleischhacker Pool House site emerges as a great connection point between the Zoo and the coast, with opportunities to engage the Zoo’s conservation mission. Parking areas will be re-organized to improve experience for beach goers while maintaining good coastal access. Green infrastructure opportunities in the new parking areas and along the site’s thoroughfares will beautify the streetscape while retaining and infiltrating stormwater. The intersections of Great Highway/Sloat and Sloat/Skyline have been identified as key important gateways to the improved landscape, and could include elements like interpretive signage and bike parking. New locations will be determined to host amenities like restrooms, seating, and scenic overlooks.
The Open Space Design study enables further collaborations between the different OBMP partner agencies for joint management of the open space areas and facilities. These include the GGNRA, SF Department of Public Works, SF Recreation and Park Department, and SF Public Utilities Commission. Beach users and community members are invited to help the team develop design and programming ideas during our Open House on May, 10th.
What is the Coastal Management Framework?
SPUR, our coastal engineering consulting team and partner agencies are working together to develop a Coastal Management Framework (CMF). This implementation study, funded by San Francisco Public Utilities Commission, will define a series of projects to protect Ocean Beach and threatened infrastructure from the dual pressures of extreme weather events and sea level rise in an adaptive and responsive manner. Based on the Ocean Beach Master Plan (OBMP) recommendations, it will delineate coastal protection action plans for three different time spans: an immediate-term (1-3 years), an interim (3-10 years) and a long-term (10-40 years).
Immediate - Term Coastal Erosion Management Plan
While the long-term strategies of the CMF are developed, Ocean Beach still faces the potential threat of a severe storm that could exacerbate current erosion issues, particularly at the “hot spot” at the south end of South Ocean Beach. The Immediate-Term Management plan covers the first three storm seasons and identifies a package of softer coastal management tools that have proven successful in recent efforts to address erosion. Proposed interventions include the combination of sand placement between the high tide line and the eroding beach bluffs with sandbag structures that can be filled in advance nearby and deployed rapidly. Another measure under consideration is to consolidate concrete rubble that is currently on the beach into an erosion-resistant slope, protecting the bluff toe and getting it off the beach. These recommendations can be implemented incrementally, are reversible in nature, have limited environmental impact and serve multiple objectives, consistent with the OBMP.
Ocean Beach Wind Blown Sand Management
The 2012 Sand Backpassing Project proved to be an effective measure against erosion and a successful interagency partnership. However, it came with some unintended consequences. Dr. Peter Baye and coastal engineers from ESA PWA and Moffatt & Nichol Engineers have identified a series of sand stabilizing techniques to address the issue of wind-blown sand that is transported onto the bluff-top parking and roadways. These measures can help SPUR, the National Park Service and the City and County of San Francisco in implementing future beach nourishment projects. Driftwood jams and placement of shell fragments or coarser sands can trap the sand in place and limit its transfer while blending harmoniously within the beach environment. Together with information signs, they can also direct beachgoers toward limited access points.These practices minimize recreational and aesthetic nuisances and maintain public beach access. Demonstration projects of windblown sand management techniques will be developed and incorporated into future sand placement projects.
Vulnerability Analysis and Coastal Engineering Feasibility Study
The consulting team is also developing a vulnerability and coastal engineering feasibility study to determine the most appropriate long-term strategies and actions for Ocean Beach. The vulnerability assessment indicates limited vulnerability in the immediate term but widespread vulnerability in coming decades. New findings support the OBMP vision of replacing current revetments with a low profile structure combined with managed retreat and realignment. Various structural alternatives that can provide bluff support and adequate protection to the critical infrastructure of Lake Merced Tunnel (LMT) are possible. Options like a jet grout or secant pile structure show particular promise since they can be implemented from the top without disrupting the bluff. These measures can allow for bluff restoration, beach cleanup, improved access, and various recreational opportunities. The team will perform additional modelling and collect supplementary geotechnical information to develop a better understanding of the effect of the changing coastline on the LMT.
As regulatory and permitting approvals for the Immediate-Term Management Plan are pending, the proposed approaches will be presented to the public to gather feedback at an open house on May 10th. Fostering interagency collaboration is a pivotal element for enabling the coastal management projects. There is a great opportunity of coordinating the different beach monitoring efforts between the partner agencies. The final goal of the CMF is to create a report that will set the stage for an agreement between SFPUC, Army Corps of Engineers and Golden Gate National Recreation Area on a Coastal Protection Strategy until 2050. This agreement will also describe the steps needed for funding, environmental review and permitting processes to streamline future projects.
When you think of a city’s circulation system, you might marvel at its network of streets, rail tracks and public transportation but another essential system lies underground – largely hidden and unremarked. The city’s network of storm drains, culverts and sewer pipes is essential to public health and environmental quality. Recently these two worlds collided when the Muni buses and trains became vehicles for San Francisco’s Public Utilities Commission advertisements, giving this hardworking system some well-deserved visibility around the city. This creative ad campaign certainly made me curious about how San Francisco’s wastewater system functions, and soon afterwards I found myself taking a tour of one of its vital components: the Oceanside Water Pollution Control Plant. It was a fascinating experience shedding light on the inner workings of this impressive facility that provides an incredibly valuable service to the city’s residents while preserving the ocean’s water quality.
The Oceanside Water Pollution Control Plant
San Francisco is served by three wastewater treatment facilities: North Point near Fisherman’s Wharf, Southeast Wastewater Treatment Plant in Bayview Hunter’s Point and Oceanside Water Pollution Control Plant near Ocean Beach. Oceanside is the newest facility of the three, built in 1993 as a result of the Federal Clean Water Act upgrade. It replaced the old Richmond Sunset Water Pollution Control Plant from 1935 that was situated in Golden Gate Park. Adjacent to the San Francisco Zoo, this modern plant is engineered for a future Zoo expansion over its roof, able to withstand 300 pounds per square foot as a future Mammal Center. The plant’s facilities are designed to be largely out of sight from the adjacent recreational areas with 70% of its 12 acres located underground, mainly for odor and noise purposes. Its state of the art HVAC system and sophisticated odor control units limit impacts on nearby neighborhoods.
The Oceanside Treatment Plant is specially engineered for coming earthqaukes as well as a future Zoo expansion over its roof. Image by Maria Bakali.
How the system works
San Francisco is the only major city on the California coast with a city-wide combined sewer system. The wastewater load fluctuates depending on weather conditions. In dry weather sewage travels through a network of pipes to the Westside Transport Box, a rectangular tube under the Great Highway between Lincoln and Sloat Boulevards. From there it flows to the Westside pump station at Sloat Boulevard, where it is pumped to the Oceanside Water Pollution Control Plant for treatment. The secondary-treated effluent is discharged 4.5 miles out to the ocean through the 80 feet deep Southwest Ocean Outfall. When the plant’s capacity is overwhelmed in extreme wet weather conditions, the transport box and the Lake Merced Tunnel fill up and retain the combined flow. Overflow there is decanted through a second chamber in the Westside Transport box and a second set of pumps transport the decanted flow to the deep ocean outfall. Only when that system’s capacity is exceeded do combined discharges occur, through seven outfall structures, three on Ocean Beach, one at Mile Rock and three near the northern beaches of China and Baker beaches.
The 200 tons of biosolids produced daily as remainders of wastewater’s secondary treatment are regionally transported for agricultural land application purposes or for landfill beneficial reuse. In addition the methane produced in the plant’s digesters is used to power the plant, covering 30% of its electrical needs. Most of the system’s functions are automated (60%), with the plant’s engineers, chemists and marine biologists monitoring the plant’s good operation and the quality of the ocean’s environment and ecosystems respectively.
Why is this facility important
The Oceanside Water Pollution Control Plant is a very efficient system, serving the city’s Westside neighborhoods and watersheds while treating 20% of the city’s average annual wastewater flows. It is an award winning facility whose prizes include the 2003 Large Plant of the Year Award and the 2004 US Environmental Protection Agency National Clean Water Act Recognition Award for Operations and Maintenance Excellence. This expensive piece of infrastructure is at the early stages of its operating cycle and maintaining its good performance and operation for the rest of this cycle is vital.
There are, however, some significant challenges in doing so. The main threat to the facility is coastal erosion that could damage the Lake Merced Tunel underneath the Great Highway. With the sea level rise posing an imminent hazard, future erosion issues most likely will worsen if no comprehensive coastal management is set in place. Another question is how the current infrastructure can deal with the future combined sewer loads. To relieve some stress put on the system during extreme weather events, Public Utilities Commission (PUC) is moving forward with projects that combine grey and green infrastructure and integrate innovative stormwater management solutions of Low Impact Development (LID).
OBMP and the Oceanside Water Pollution Control Plant
One of the major goals of the Ocean Beach Master Plan is to protect in place the Oceanside system components for the next decades. According to the OBMP vision a combination of managed retreat, beach nourishment and low profile structural protection will substitute current revetments providing a more environmentally sensitive and aesthetically preferable solution. These measures will also allow for improved recreational and ecological opportunities along the beach and the surrounding area, benefiting residents and visitors alike. The PUC is working very closely with SPUR, the coastal engineering team and other partner agencies on developing a Coastal Management Framework, that will delineate coastal protection strategies until 2050. For more updates on developments on Ocean Beach join SPUR’s new public outreach efforts this May. Stay connected with us through Twitter, Facebook and our Blog!
Want to know more about the Oceanside Treatment Plant? Sign up for a free tour organized by San Francisco Public Utilities Commission.
Amazing ocean views once difficult to capture from a car seat can now be enjoyed by anyone who makes a short trip to Pacifica’s Devil’s Slide Trail. After nearly 20 years, a project to redirect traffic through mountain tunnels and convert this former portion of Highway 1 to a non-motorized multi-use coastal trail is finally complete. The trail opened to public on March 27 and welcomes hikers, cyclists, horse riders and leashed dogs 24 hours a day, all year around. With its similarities to erosion-damaged sections of the Great Highway, Devil's Slide offers a model for implementing some of the recommendations in SPUR’s Ocean Beach Master Plan.
Devil’s Slide History
The rugged headland midway between Montara and the Linda Mar District of Pacifica, with its steep unstable coastal cliffs, bears the distinct name “Devil’s Slide.” The terrain’s propensity for landslides and erosion did not hinder the construction of Highway 1 back in 1937. Only three years after the highway’s opening, the first major landslide caused extensive damages to the road. In the following years, periods of destruction and rebuilding alternated, with the winters of 1983 and 1995 marking remarkably lengthy closures, leading decisionmakers to plan for alternatives.
The initial Caltrans proposal to construct a four-to-six-lane freeway bypass was opposed by grassroots environmental organizations who favored the construction of two 30-foot wide tunnels instead. This safer and more environmentally sensiitive approach, which also allowed for a separate coastal recreational trail, found considerable support with local governments and was approved in 1996 by San Mateo County voters. Multiple agencies including San Mateo County, the City of Pacifica, Caltrans, the California Coastal Commission and the National Park Service partnered to bring the plan to fruition. The Tom Lantos Tunnels — officially named after the congressman who played a major role in securing funding for the project and also known as "the people’s tunnels” after the novel grassroots victory — opened to traffic in March 2013, a year before the trail’s opening.
Devil’s Slide Coastal Trail
The 1.3 mile, 24-feet wide repaved trail provides separated pedestrian walkways and bike lanes featuring painted signage to avoid the extensive use of sign posts. Accessibility improvements and protective rail installments increase safety, while educational graphic panels about the area’s geology, environment and history provide information to visitors. Three overlook areas with benches and observation telescopes offer spectacular scenic vistas, showcasing the coast’s natural beauty. The trail’s critical proximity to bird nesting locations requires special protection measures to decrease visitors’ visibility and ensure habitat protection. Devil’s Slide becomes part of the California Coastal Trail connecting Mori Point to Pillar Point, and emerges as a regional destination, expected to attract 80,000 visitors annually.
Car access to the trailheads is granted through two small parking areas at the trail’s ends, although emphasis is put on public transportation, carpooling and biking. SamTrans bus stops at the south end of the tunnel and free Pacifica city shuttles during weekends serve the visitors who choose transit to reach the trail. Negotiations with private owners are in progress to ensure long-term pedestrian access from Pacifica to the trail.
Ocean Beach Master Plan
The Devil’s Slide project has significant similarities to SPUR’s Ocean Beach Master Plan. First, it addresses the impacts of coastal erosion on California’s coast in a comprehensive manner, and second, it does so by fostering partnerships among a number of different public agencies. Because the Great Highway has its own history of lengthy closures under extreme weather and erosion, the Ocean Beach Master Plan recommends the closure of the south reach of the Great Highway between Sloat and Skyline boulevards. Under the plan, the abandoned lanes will be transformed into a multi-use path that celebrates open space and ecological restoration through managed retreat. The coastal trail along Ocean Beach will provide critical connections to the surrounding recreational resources of the area, creating a continuous promenade from Fort Funston up to Lands End. The project combines coastal adaptation management while giving San Franciscans and visitors a unique resource of immense environmental and recreational value. Changes on the Great Highway will be implemented incrementally according to the timeframes set by the Ocean Beach Master Plan implementation studies. Check SPUR's Ocean Beach Master Plan page for updates.
Under the threat of sea level rise, a number of coastal communities around the world will have to decide between protecting coastal homes and structures or giving way to the persistent impacts of coastal erosion by retreating from the coastline.
A recent FEMA-funded study warned that each year, on average 1500 homes and the land on which they are built could erode into the ocean due to rising sea levels and extreme weather events. The upcoming Intergovernmental Panel on Climate Change’s next Assessment Report (due to be released next year) is expected to include increased sea level rise estimates, as it will be its first to account for melting ice sheets. Continued research is making it increasingly apparent that many of the coastal management and development strategies employed thus far must evolve.
Until quite recently, the overwhelming response to coastal erosion—especially in developed areas—has been to armor the coastlines through hard engineering strategies, such as seawalls and piles of rock referred to as riprap or revetments. However, coastal armoring interrupts sediment patterns and intensifies erosion elsewhere. As a result, a number of coastal areas in the state have begun to consider managed retreat, an approach that involves giving space for natural processes.
Among the key benefits of managed retreat are the restoration of native processes and sediment patterns. Managed retreat can also be used in conjunction with soft engineering strategies, allowing for customizable solutions to meet the needs of different coastal land uses and characteristics. This article highlights a few instances in the state in which managed retreat has been considered as an alternative to coastal armoring.
Goleta Beach, Goleta, CA
Goleta Beach, as seen from behind rock revetments. Image courtesy of Flickr user Damian Gadal
Managed retreat can be a contentious coastal management strategy because it requires the removal or relocation of man-made structures or amenities away from the coast. This has been highlighted in Santa Barbara County, where a plan to remove parking spaces and rock revetments at Goleta Beach Park has been contested by a local community group and the Chamber of Commerce. At the center of the issue is Goleta Beach Park, a stretch of lawn and parkland currently protected by revetments.
Friends of Goleta Beach Park, the opponents of the County Planning Department’s proposed plan—dubbed “Goleta Beach 2.0”—claim that the loss of recreational opportunities and approximately one-fifth of the parking availability will dramatically hamper coastal access at Goleta Beach, which draws an estimated 1.5 million visitors per year.
Proponents of the plan, including the Surfrider Foundation and Environmental Defense Center, are calling for managed retreat in order to ensure the long-term stability of the beach. Under current conditions, the revetments protecting the park and parking lots exacerbate beach erosion during storm events. Should the County go forth with the plan, a number of “at-risk” utility lines and a bike path would be moved inland for protection.
Surfer's Point, Ventura, CA
Just 40 miles to the south of Goleta Beach, Ventura’s popular Surfer’s Point serves as a model for what could soon take place at Goleta. After attempting to bolster the shoreline with boulders to protect a bike path and parking lot that were being eaten away by waves, erosion intensified down the coast. Proposals of an underground seawall, which would have ruined the breakpoint—and thus, the namesake—at Surfer’s Point were briefly considered as an alternative, but managed retreat was decided upon as the ideal way to maintain natural sediment patterns and restore the beach.
The project, which was led in part by Louis White, PE, and Bob Battalio, PE, of ESA PWA—who are working closely with SPUR on the Ocean Beach Master Plan—included relocation of the existing bike path and parking lot 60 feet inland, then the removal of riprap and its replacement with thousands of tons of sand and cobble stone. The beach is currently being returned to native dune ecology.
Ocean Beach Master Plan
The Ocean Beach Master Plan (OBMP) recommends managed retreat south of Sloat Boulevard, a long-term process that would involve the removal of the Great Highway and the creation of a multi-use recreational trail connecting to Fort Funston. Most importantly, it would allow for the restoration of native dunes, increasing the recreational and ecological function of the area. The OBMP also recommends narrowing the Great Highway between Lincoln and Sloat in order to create a multimodal promenade and allow for a natural dunescape.
Weighing the Costs and Benefits of Relocation
As a state that has long devoted premiere shoreline to expensive homes and businesses, managed retreat represents a paradigm shift. However, as more research goes into sea level rise and the impacts of sediment pattern interruption caused by hard engineering strategies, it is likely that coastal management strategies will more frequently involve managed retreat. Relocation assistance and buy-back programs help make managed retreat a more politically friendly option, especially for coastal property owners.
As always, solutions should be explored on a case-by-case basis. Last month’s blog post about New York City highlighted the city’s inability to retreat in developed areas due to infrastructure needs and population density along many of the shorelines. As more and more areas of the coastline fall under the threat of erosion, it will be important to figure out costs and benefits associated with protecting or relocating structures. How will coastal jurisdictions decide what to protect, and at what financial and ecological costs?
The National Oceanic and Atmospheric Administration (NOAA) has encouraged coastal states to utilize “No Build Zones” through Coastal Management Programs, which are required by the Coastal Zone Management Act (CZMA) of 1972. The CZMA requires states to manage coastal development in order to minimize losses due to flooding, storm surges, or erosion, as well as to protect natural coastal features. Other means used to prevent and limit coastal development include setbacks, which require development to be a specified distance from the water’s edge, and rolling easements, which allow development, but without any erosion control methods.
While new coastal development will undoubtedly take a far more precautionary approach in the coming years, existing communities will have a big decision to make: armor or retreat?
As a city with a combined sewer system—meaning that stormwater enters the wastewater treatment system—the San Francisco Public Utilities Commission (SFPUC) is undertaking projects around the city to divert stormwater into landscaping, in order to reduce demand on the aging sewer system. One of the eight green infrastructure projects in the SFPUC’s 20 year, multi-billion dollar Sewer System Improvement Program is the Sunset Boulevard Greenway, which could reduce the frequency of combined sewer discharges into the Pacific Ocean along Ocean Beach.
According to the SFPUC, the sewer system treats about 80 million gallons per day during dry weather, a number that swells to 500 million during rainy weather. When the Oceanside Treatment Plant and nearby storage structures—which serve the city’s western watersheds—exceed capacity, combined sewer discharges are released directly onto Ocean Beach after receiving only primary treatment.
Combined sewer systems are predominantly found in older communities in the Midwest and Northeast United States, with the only other combined sewer system in California being found in an older portion of Sacramento. For coastal communities without combined sewer systems, stormwater flows directly into creeks and rivers, reaching the ocean after traveling through catch basins that remove trash—but not chemical pollutants, like paint or motor oil—and require frequent cleanings. Although combined sewers can result wet weather overflows, they are preferable to year-round untreated stormwater.
Low-impact design (LID) strategies like those recommended in the SFPUC Sunset Boulevard Greenway Project represent one solution, allowing for water to soak into the ground, thus removing pollutants through a natural filtration system and mimicking pre-development conditions. According to SFPUC estimates, the Sunset Boulevard Greenway Project would improve stormwater management for over 20 acres of paved surfaces, capturing more than 10 million gallons of runoff annually. In turn, this would lead to an estimated annual reduction of 5 million gallons of combined sewer discharges into the Pacific Ocean.
In addition to reducing the detrimental urbanizing impacts that cities have on water systems, LID projects can bring much-needed greenery and natural landscapes into cities, often doubling as beautifying measures. LID is achieved through rain gardens, sidewalk gardens and trees—a single street tree removes about 1,000 gallons of stormwater from the sewer annually—and creeks, bioswales, ponds, or restored wetlands (see more about these, and other forms of green infrastructure in a recent blog post by Laura Tam, SPUR’s Sustainable Development Policy Director.
Although specific plans for the Sunset Boulevard Greenway Project will not be released until the planning phase, which is projected to take place between Winter 2013 and Spring 2014, the SFPUC is emphasizing a number of improvements spanning beyond stormwater management, including beautification, revitalized pedestrian and cyclist space and trail use, habitat enhancement, community recreation space, and educational benefits.
The influence that low-impact design projects have on streetscape improvements make them an attractive option for interagency collaboration. San Francisco’s Department of Public Works is incorporating LID strategies within many of its projects as part of the Great Streets Program, including its Taraval Streetscape Improvements Project. LID features are also included in San Francisco Municipal Transportation Agency’s Livable Streets projects (for traffic calming, among other purposes) and Planning Department’s Pavement to Parks Program.
The Ocean Beach Master Plan (OBMP) includes a recommendation to employ LID throughout adjacent neighborhoods and along the Great Highway to address stormwater management. Much of the Sunset District lends itself well to potential future LID projects because of its wide, hilly streets, many of which are sparsely vegetated and contain paved-over front yards.
To help plan the Sunset Boulevard Greenway, take the SFPUC’s survey.
Future flickers for Ocean Beach bonfires SF Bay News 02/9/2015
California braces for "storm of the decade" CBS News, 12/9/2014
Why S.F. is moving 42,000 tons of sand down Ocean Beach SF Gate, 12/5/2014
San Francisco, Sonoma recognized by White House for Climate Action SF Gate, 12/3/2014
White House checks out S.F.'s plan to Save Ocean Beach SF Chronicle, 6/20/14
San Franciscans in the Dark about Flood Hazards Climate Central, 06/20/14
SPUR's Plans for Ocean Beach Get Refined and Rendered Curbed, 06/06/14
Taking Action on Sea Level Rise SPUR, 04/10/14
San Francisco plans expensive ‘managed retreat’ from rising seas Grist, 02/04/13
Ocean Beach Master Plan Envisions Big Changes SF Public Press, 02/04/13
San Francisco a Test Case for Coping with Rising Seas KQED, 02/01/13
New plan crafted to limit Ocean Beach erosion SF Chronicle, 11/02/12
Ocean Beach sand management project wraps up ABC Local News, 09/20/12
Sand Mangement Project to partly close Great Highway OB Bulletin, 08/19/12
Great Highway lane work delayed SF Chronicle, 08/09/12
Mayor Lee Celebrates SPUR Ocean Beach Master Plan SF Mayor’s Office, 07/26/12
Turning the Tide at Ocean Beach KQED News, 07/26/12
Shifting sand to be transported elsewhere in San Francisco SF Examiner, 07/23/12
Ocean Beach sand plan could help curb erosion south of Sloat OB Bulletin 07/20/12
Ocean Beach master plan maps $300M project SF Business Journal, 06/22/12
Stay or go? Communities are eyeing a retreat from sea NBC News, 06/02/12
San Francisco's Coast and the Rising Sea KQED, 04/10/12
San Francisco's Battle With Mother Nature Planetizen, 03/28/12
Coastal Erosion in SF Prompts Planning and Debate KQED, 03/26/12
Both Coasts Watch Closely as SF Faces Erosion The New York Times, 03/24/12
Makeover could mean changes on Great Highway SF Examiner, 11/12/11
OBMP Envisions Big Changes for Great Highway KQED, 11/07/11
Erosion expected to strip economic value of Ocean Beach OB Bulletin, 09/13/11
Erosion problems threaten the future of Ocean Beach ABC Local News, 09/05/11
State panel rejects city's repairs to Ocean Beach SF Chronicle, 07/15/11
Violent Pacific storms of 2010 worst on record SF Chronicle, 07/14/11
Public urged to help decide fixes for Ocean Beach erosion Sunset Beacon, 02/01/11
Forces of Nature are Working to Destroy Ocean Beach The Bay Citizen, 01/25/11
On the Brink of an Ocean Beach Master Plan OB Bulletin, 09/21/10
Is It Worth It to Save Oceanfront Development? The New York Times, 09/13/10
Experts Call for Long-Term Fix for Beach Erosion Sunset Beacon, 11/01/10
Ocean Beach due for an overhaul SF Examiner, 07/08/08
The Impacts of Sea-Level Rise on the California Coast Pacific Institute
Coastal Regional Sediment Management Project USACE, CA Resources Agency
Our Coast Our Future (OCOF) GFNMS, PRBO, USGS
Western Shoreline Plan (Local Coastal Program) SF Planning
Ocean Beach Task Force Summary (2005) Ocean Beach Task Force
South Ocean Beach - Shore Management Discussion Bob Battalio, PE