Oro Loma Sanitary District – San Lorenzo Shoreline Adaptation & Demonstration Project
Public Works
In 2023, Brannon Corporation completed The San Lorenzo Shoreline Adaptation & Demonstration Project for the Oro Loma Sanitary District, which involved sensitive species, including the endangered Salt Marsh Mouse and California Clapper Rail. This was a pilot project, the first of its kind, to demonstrate innovative, nature-based wastewater management solutions. In partnership with its client, Brannon enacted a shoreline adaptation plan to address sea level rise, water quality protection, and infrastructure sustainability – to create a treatment wetland and ecotone slope adjacent to the water treatment facility, produce a resilient barrier to rising sea levels, increase denitrification treatment to reduce nutrient and contaminant discharges, provide an upland refuge and transition zone for wildlife, and reestablish grassland and Bayland habitats.
      • PROBLEM: Vulnerability of infrastructure existing on reclaimed tidal marshlands, which required innovative shoreline adaptation strategies to serve as the demonstration model for the surrounding shoreline area facing similar vulnerabilities.
      • SOLUTION: Construction of new horizontal levee cells included clearing and excavation of two existing earthen sloped cells and replacement with eight smaller cells with a new grade and individual feed/drain piping; re-construction of new reconfigured Ecotone Sub-cells with varying treatment zone blends, slope, and Ecotone Soil & Ecotone Top Soil; installation of yard irrigation piping to deliver and collect treated wastewater to/from the new Ecotone Sub-cells; installation of flow monitoring and control valves (including attachment of antenna to wood post).
      • TRANSFORMATION: Completion of this experimental project holds marked significance, as it helped researchers understand the functionality and performance of a nature-based wastewater treatment design, which proved beneficial results in the areas of flood risk, water quality, and habitat enhancement. Such efforts are critical for improved replicability, potentially influencing similar environmental projects regionally and beyond. The need for such innovative strategies allowed for collaboration between Brannon and Oro Loma Sanitation District to secure future grant funding to finance other potential projects similar in nature, allowing Brannon to exemplify its motto as the “Trusted Partner in Collaborative Construction.“