San Leandro Resilience Project
The Kellogg Resiliency Project, led by the Fairfield-Suisun Sewer District in partnership with Suisun City (the landowner), is a community co-design, multi-benefit initiative aimed at addressing vulnerabilities related to sea-level rise (SLR), flooding, and fire risk. Located adjacent to Suisun Slough, the project site includes existing stormwater infrastructure and is identified as one of the first areas in Suisun City likely to flood under future SLR scenarios. Without improvements, the site poses a risk to surrounding properties, stormwater management systems, and wastewater infrastructure critical to Fairfield-Suisun Sewer District’s operations.
Scope of Services
Terraphase supported the project by identifying, compiling, and evaluating existing information to characterize site physical, operational, and permitting constraints, as well as potential opportunities. Based on this assessment, Terraphase developed a series of project alternatives and fact sheets to present to the community to address initial project goals, such as SLR flood protection using nature-based solutions, fire hazard reduction, habitat creation, and potential recreational and educational elements. Community input was central to the process, with feedback gathered through outreach efforts and a design charrette informing the refinement of project alternatives. A 30% civil engineering design package and planning-level cost estimate will be prepared for the preferred alternative to support regulatory permitting and finalization of the design in the next phase of the project.
Notable Accomplishments
- Developed multiple nature-based retrofit alternatives and community-facing fact sheets
- Successfully facilitated community engagement through a design charrette and outreach materials
- Supported planning for a 30% design and cost estimate to guide final project development
San Leandro Tony Lema Landfill Long-Term Flood Protection and Adaptation Plan
This project in San Leandro, California was conducted to support compliance with the 2022 San Francisco Bay Regional Water Quality Control Board (RWQCB) Amendment to Waste Discharge Requirements for Long-Term Flood Protection Considerations at Closed and Operating Municipal Solid Waste Bayfront Landfills.
Scope of Services
Terraphase completed a comprehensive background review of all available information for this project, including site-specific climate hazard data developed by the City of San Leandro, relevant regulatory guidance, and historical landfill documentation. Using available Light Detection and Ranging (LiDAR) and survey data, we assessed current site topography and conducted a detailed analysis of projected sea-level rise (SLR), groundwater elevation rise, and surface water inundation scenarios for 2050 and 2100. Our assessment followed guidance from the California Ocean Protection Council (OPC) and Bay Conservation and Development Commission (BCDC) Adapting to Rising Tides framework. Data sources included flood and groundwater mapping from the San Francisco Estuary Institute and the U.S. Geologic Survey (USGS) Coastal Storm Modeling System. The study culminated in the development of a phased flood adaptation plan with recommended strategies to enhance site resilience over time.
Notable Accomplishments
- Conducted site-specific flood and groundwater rise analysis for 2050 and 2100 SLR scenarios
- Prepared a site vulnerability assessment and phased adaptation strategy
- Proposed conceptual adaptation measures including berms, groundwater controls, irrigation strategies, and nature-based solutions
Fairfield Suisun Sewer District Kellogg Resiliency Project
The Kellogg Resiliency Project, led by the Fairfield-Suisun Sewer District in partnership with Suisun City, California (the landowner), is a community co-design, multi-benefit initiative aimed at addressing vulnerabilities related to sea-level rise (SLR), flooding, and fire risk. Located adjacent to Suisun Slough, the project site includes existing stormwater infrastructure and is identified as one of the first areas in Suisun City likely to flood under future SLR scenarios. Without improvements, the site poses a risk to surrounding properties, stormwater management systems, and wastewater infrastructure critical to Fairfield-Suisun Sewer District’s operations.
Scope of Services
Terraphase supported the project by identifying, compiling, and evaluating existing information to characterize site physical, operational, and permitting constraints, as well as potential opportunities. Based on this assessment, Terraphase developed a series of project alternatives and fact sheets to present to the community to address initial project goals, such as SLR flood protection using nature-based solutions, fire hazard reduction, habitat creation, and potential recreational and educational elements. Community input was central to the process, with feedback gathered through outreach efforts and a design charrette informing the refinement of project alternatives. A 30% civil engineering design package and planning-level cost estimate will be prepared for the preferred alternative to support regulatory permitting and finalization of the design in the next phase of the project.
Notable Accomplishments
- Developed multiple nature-based retrofit alternatives and community-facing fact sheets
- Successfully facilitated community engagement through a design charrette and outreach materials
- Supported planning for a 30% design and cost estimate to guide final project development
