Wastewater and Water Systems Climate Adaptation Plan

Flooding and erosion during storms already affect the City’s wastewater and water infrastructure. The severity of these impacts is anticipated to accelerate significantly in the coming decades due to climate changes, including rising sea levels and heavier rainfall during storms. The City developed the Wastewater and Water Systems Climate Adaptation Plan to evaluate the current and future impacts on the City's water and wastewater systems and outline a phased approach for adapting these systems over time.

This Plan is part of a broader City Adaptation and Resilience Program, which monitors changing conditions and adapts infrastructure in phases. The project is jointly funded by the California Coastal Commission, the California Coastal Conservancy, and the City.

Largest Risks

The Plan analyzes the impacts on all parts of the wastewater and water systems within the City from flooding, erosion, sea level rise, changing rainfall, wildfire, drought, extreme heat, and groundwater. The Plan identifies increased flooding of the wastewater system as the highest priority risk to City infrastructure, particularly in low-lying areas from the Waterfront to just north of Highway 101. 

During storms, floodwaters can overwhelm the sewer collection system, leading to sanitary sewer overflows. Access roads to the El Estero Water Resource Center currently flood during high rainfall events, and these conditions are expected to worsen with increased rainfall rates and sea level rise. In the coming decades, rising sea levels and coastal storm surges also threaten to introduce saltwater into the wastewater collection system.  The center’s sewage treatment process depends on bacteria that are intolerant to seawater, so any saltwater flooding of the system causes significant disruptions in operations.