Coastal Resiliency Concepts

The Project will incorporate a variety of nature-based features and SLR adaptation strategies including:

A Living Levee: Elevation of the Class 1 Bikeway using an earthen living levee concept and ecotone slope to increase sea level rise resilience); and
Multi-purpose Detention Basin/Stormwater Improvements: A flood control structure/outlet will manage floodwater into the system and control stormwater discharge to the Bay.

The Project also provides additional coastal access and environmental benefits, including:

Coastal access trail enhancements: Adding separated pedestrian and bicycle paths alongside the Bikeway to provide connectivity and reduce conflicts between bikes and pedestrians
Habitat Enhancements: Enhance and restore existing tidal marsh in alignment with implementation of the living levees and activities to increase tidal flushing in Pond 10A.

Problem and Need

The Bayside Neighborhood is one of the most vulnerable segments of Imperial Beach to coastal flooding. The Bikeway and the residential community in this location are prone to flooding during existing extreme tides near 7th Street and Basswood Avenue. Projected sea level rise will drastically increase the risk of tidal (non-storm) flooding at this location with projected 3.5 feet of increase sea levels impacting large portions of SR75 and the neighborhood.

Project Area

The Project area is divided into three segments:

Segment 1 includes the area that wraps around Pond 10A
Segment 2 is 7th Street to 8th Street
Segment 3 is 8th Street to 10th Street and includes the Bayside Elementary School (the latter is planned to be a joint-use park for use by the public during non-school hours)

Concept Options by Segment

The following images and diagrams illustrate the currently proposed coastal resiliency design concepts intended to protect the Bayside neighborhood of the City of Imperial Beach from existing coastal flooding and future sea level rise and extreme onshore precipitation events. The Project's development area is divided into three Segments, each with different design options.