Building Climate Change Resiliency Along the Bay with Green Infrastructure & Treated Wastewater
|Sponsoring Agency||San Francisco Estuary Partnership|
|Subregions||('North Bay', 'East Bay', 'South Bay')|
|Counties||Alameda, Santa Clara?, Marin?|
|Watershed Tributary||San Lorenzo, Alameda Creek|
|Public or private land?||('Public',)|
|Location (lat/lon)||37.6671, -122.1567|
|Location Description||Oro Loma Sanitary District|
Building Climate Change Resiliency Along the Bay Shoreline with Green Infrastructure and Treated Wastewater proposes to create a regional partnership of agencies that would redesign existing wastewater treatment operations by integrating natural bay ecosystem processes into a new water treatment paradigm. This new Green Infrastructure paradigm will incorporate adjacent wetland restoration projects into redesigned wastewater treatment plant operations in a manner that increases treatment plant efficacy and mitigates adverse climate change impacts both on plant operations and on the adjacent developed communities along the shoreline. The goals of the partnership are: a. to improve wastewater treatment by using natural marsh habitats to pre-treat pollutants; b. to protect vulnerable wastewater treatment plants and adjacent shorelines from rising sea levels; c. to incorporate ongoing restoration of adjacent tidal wetland habitats into a larger design to enhance those marshes and employ them as natural barriers against regional flooding and sea level rise; and, d. to determine the most cost-effective ways for wastewater plants to lower their nutrient and emerging contaminant discharges to the Bay – now a focus of concern of the San Francisco RWQCB The project partners propose to construct a series of innovative pilot ecotone slope projects along the southeastern San Francisco Bay shoreline. Participating POTWs in the form of East Bay Dischargers Association and its member agencies will collaborate with resource managers (i.e. the Don Edwards San Francisco Bay National Wildlife Refuge, Hayward Recreational Park District, and other parks/wetlands managers) and regulatory agencies (Regional Water Board, Fish and Game, DWR) to plan and permit these projects. The aim of the partnership is to expand its membership to include all Bay POTWs and adjacent land use management agencies in a unified effort to test, refine and construct the new Green Infrastructure paradigm. The first pilot project would be carried out at the Oro Loma Water Pollution Control facility in San Lorenzo where a demonstration ecotone slope would be constructed at its site. Based upon the success and lessons learned from the Oro Loma pilot, a second series of pilots is proposed for Union Sanitary District, City of Hayward, City of San Jose, and the Novato Sanitary District. Planning and permitting for this second series are included in the present project.
Building Climate Change Resiliency Along the Bay Shoreline with Green Infrastructure and Treated Wastewater proposes to establish a partnership to construct a series of pilot ecotone slope projects integrated with San Francisco Bay wastewater treatment plants. The goals of this project are: to improve wastewater treatment by using natural marsh habitats to pre-treat pollutants; to protect vulnerable wastewater treatment plants and adjacent improvements from rising sea levels; to use treated wastewater as a resource in marsh restoration; to integrate ongoing restoration of adjacent tidal wetland habitats into a larger design to employ those restored marshes as natural barriers against regional flooding and sea level rise; and to investigate new opportunities for wastewater plants to lower their nutrient and emerging contaminant discharges to the Bay by using the Green Infrastructure model.
Part 2 - Detail
At least 22 wastewater treatment plants around San Francisco Bay are vulnerable to the effects of sea level rise over the next century. Oro Loma Sanitary District (OLSD) has a conceptual design to create a seepage ecotone slope to restore historical moist grassland / bayland ecotone while treating reclaimed wastewater from equalization facilities and increasing its resilience to sea level rise. This project will be permitted and constructed as the first demonstration project of Building Resiliency Along the Bay with Green Infrastructure and Treated Wastewater. Additionally a treatment facility retrofit that supports wetlands accretion will be designed and permitted at Union Sanitary District, City of Hayward, and Novato Sanitary District based upon confirmation of the expected results in the pilot study.
A scientific peer-review committee will be convened to provide technical review and guidance for the project, both for the treatment wetlands and the ecotone slope. The interdisciplinary committee will consist of leading scientists, practitioners, and managers from around the Bay who are well versed in the challenges, opportunities, and questions that the project raises. The advisory committee will provide guidance for design, monitoring design, adaptive management, and analysis of results. In addition to the design, permitting and construction of innovative treatment facilities, the demonstration project will generate design guidance and implementation recommendations that will be disseminated through outreach to the Bay Area’s many wastewater treatment facilities. The potential impact of this project is vast: if 25 percent of the Bay Area’s wastewater treatment plants are able to build ecotone slopes (based upon Oro Loma’s successful demonstration) then over 5,000 acres of moist grassland / bayland ecotone can be created around the Bay.
The aim of the partnership is to expand its membership to include all Bay POTWs and adjacent land use management agencies in a unified effort to test, refine and construct the new Green Infrastructure paradigm. The outreach component of the project will include development and dissemination of program material in print and electronic form; meetings with prospective POTW and land use management agency partners to keep them updated about progress and discuss program findings; meetings with regional policy makers to inform them about program details, including costs and benefits; meetings with community and civic organizations to build understanding and support for the project; meetings with state and federal elected officials who are ultimately responsible for oversight of program authorization and funding; and outreach to key news media providers to promote broad public awareness of and support for the project.
Oro Loma Web Page With Feasibility Study for Project and Powerpoint Overview
Oro Loma Sanitary District is in the San Lorenzo Watershed. The San Lorenzo Creek Watershed drains 48 square miles of the East Bay Hills. The Oro Loma/Castro Valley Water Pollution Control Facility is the sole treatment plant for the San Lorenzo Creek, Bockman, and Sulphur Creek Watersheds, as well as significant portions of San Leandro Creek and Estudillo Canal Watersheds. The facility treats an average dry weather flow of 12.2 mgd (Year 2011).
More than 50,000 acres of former and existing tidal marshes are immediately adjacent to the heavily developed urban shoreline of southern San Francisco Bay. An aging network of earthen levees provides flood protection for the developed shore. Sea level rise already is compromising the integrity of the levee system and causing increasingly frequent flooding of developed areas. This condition is forecast to get worse as sea level continues to rise. Major regional transportation corridors, including highway and rail, commercial and residential property, and critical infrastructure such as POTWs are at risk.
The project will demonstrate the advantages of employing the ecosystem services provided by a restored marsh system to provide critical flood and water quality protection benefits during the current era of sea level rise. The alternative approach of using traditional hardscape methods to safeguard existing public services would certainly be far more costly, perhaps prohibitively so.
In addition, large areas of marshes that are currently being restored would be threatened by flooding from sea level rise and contamination from failure to manage waste and storm water effectively. Further, the specific green infrastructure feature that is the centerpiece of the Oro Loma project—the ecotone—is targeted as central to the success of endangered species recovery. The Draft Recovery Plan for Tidal Marsh Ecosystems of Northern and Central California places priority on re-establishing terrestrial ecotones that provide high tide flood refuge cover and seasonal (spring) grassland foraging for the salt marsh harvest mouse. The list of wetland functions deemed to be of outstanding public interest that the proposed project will significantly improve, include: food chain production, habitat for aquatic and land species; dynamic surface water storage; energy dissipation; groundwater flow; nutrient cycling; removal of elements and compounds; retention of particulates; sequestration of organic carbon; maintenance of scarce plant community; maintenance of characteristic detrital biomass; maintenance of spatial structure of habitat, etc. The opportunity for improving these wetlands functions at treatment plants will be lost.
i. Water Supply (conservation, recycled water, groundwater recharge, surface storage, etc.)
ii. Water Quality
The seepage flow through an ecotone slope provides an effective, low cost, low energy, and environmentally sustainable method to nearly eliminate nutrient loadings and CEC’s from the receiving waters. If proven successfully, the project has the potential to radically improve water quality in the San Francisco Bay.
iii. Flood and Stormwater Management
The project has significant flood and stormwater management benefits. The proposed ecotone slope’s primary function is to provide an environmentally friendly, adaptable, and robust defense against flooding associated with sea level rise.
During dry weather periods, urban stormwater can be routed through the ecotone slope to provide treatment of common fertilizer, hydrocarbon, and sediment based pollutants. The proposed pilot project on the Oro Loma site will incorporate this concept by routing stormwater from an industrialized area into the ecotone.
iv. Resource Stewardship (watershed management, habitat protection and restoration, recreation, open space, etc.)
The Oro Loma seepage ecotone slope will be the first Bay Area project to replicate an engineered equivalent of moist grassland / bayland ecotone of broad, flat alluvial fans that historically graded into the tidal marshes of most of South San Francisco Bay. Historically, moist grasslands vegetation (lowland wet grassland and sedge-rush meadows) were prevalent along the Estuary and in the San Lorenzo Watershed. This now rare groundwater-seep-dependent ecotone will provide important seasonal terrestrial habitat for nesting mallards and the endangered salt marsh harvest mouse (spring foraging habitat and increasingly important terrestrial high tide refuge), particularly as sea level rises.
Groundwater, soil, and vegetation interactions of wet meadows will support important carbon and biogeochemical nutrient transformation and sequestration processes that are currently excluded from diked baylands and tidal marshes disconnected from groundwater discharges.
Additionally the project will work with resource managers (Hayward Recreational Park District, Bay Trail) to ensure genuine stewardship of the wetlands around the bay.
- Construction of 700 feet of innovative seepage ecotone slope.
- Creation of 2.4 acres of rare native moist grassland/baylands ecotone
- Development, implementation and analysis of a robust monitoring program.
- Development of design guidelines and implementation recommendations.
- Publication and dissemination of Final Report on demonstration project.
- Publication of the results of outreach to POTWs and interested parties.
- Demonstration that a seepage ecotone slope is effective in:
- nourishing moist grassland / bayland ecotone that is missing in most parts of the Estuary;
- serving as a gently sloping terrestrial gradient between tidal marshes and flood levees to act as a buffer to sea level rise; and,
- cost effective nutrient removal from wastewater.
- Establishment of a diverse palette of native plants, include creeping wildrye (Leymus triticoides, syn. Elymus triticoides), field sedge (Carex praegracilis), basket sedge (C. barbarae), wire rush (Juncus arcticus), brown-head rush and Iris rush (J. phaeocephalus, J. xiphioides), mixing with more salt-tolerant species such as saltgrass (Distichlis spicata) near the upper tidal edges.
- Establishment of increased habitat for native fauna such as Salt Marsh Harvest Mouse (Reithrodontomys raviventris) and nesting mallards.
- POTWs around Bay recognize benefits of climate change adaptation strategies. n. Implementation of large scale seepage ecotone slope projects around the Bay.
- Association of Bay Area Governments
- Bay Conservation and Development Commission
- California Coastal Comnmission
- California Department of Fish and Game
- California Water Boards
- Don Edwards San Francisco Bay National Wildlife Refuge
- San Francisco Bay Regional Water Quality Control Board
- Stanford University
- UC Berkeley
- US Environmental Protection Agency