Palo Alto Horizontal Levee

This project will be the first of its kind to beneficially reuse treated wastewater for irrigation before discharging directly to San Fransico Bay. This project is on the leading edge of a move towards integrated solutions that provide flood protection, combat sea level rise, treat wastewater, and provide enhanced habitat.

ESA designed this multi-benefit project to enhance and expand shoreline habitat along the perimeter of the Harbor Marsh in Palo Alto. The project includes creating a flood protection levee berm with a broad ecotone slope, adaptable to sea level rise, which also treats discharged wastewater from the City of Palo Alto’s Regional Water Quality Control Plant (RWQCP) before it enters the San Francisco Bay. The ecotone slope will feature grassy wet meadows, freshwater/tidal brackish marshes, and riparian scrub – historical transitional habitats decimated by development. This horizontal levee design provides an upland transition zone for marsh vegetation to adapt to rising sea levels while maintaining flood protection for the RWQCP infrastructure and supporting future regional flood protection solutions.

ESA’s design integrates the horizontal levee with regional efforts to protect low-lying infrastructure from sea-level rise, identifying a strategy for obtaining construction permits, incorporating public access, and advancing treatment effectiveness. Designed to accommodate the future construction of a regional flood protection levee between the ecotone slope and Embarcadero Road, the team leverages their experience from the successful Oro Loma Sanitary District Waste Water Treatment Plant project to expand similar initiatives around the San Francisco Bay’s perimeter.