The Preferred Alternative balances risk reduction and ecological enhancement to foster a robust and layered system of shoreline adaptation. This hybrid configuration is based upon stakeholder feedback received during the Design Alternatives process.
The line of protection includes a FEMA-certified levee that will reduce risk to inland communities by buffering the shoreline to the impacts of sea level rise and storm surge. The spatial alignment of this levee protects critical built assets and provides opportunities for shoreline restoration.
A large extent of tidal habitat is enhanced outboard of the line of protection. Tidal marshes, existing and restored, would be monitored over time with an adaptive management plan that could use sediment augmentation to sustain healthy mudflat and marsh elevations in strategic areas. New tidal marsh is restored at Frank’s West and Hayward Marsh. Vulnerable ecosystems, like the Oliver Salt Ponds, would also be restored to tidal marshes as sea levels rise and make perimeter levee maintenance less feasible.
The Bay Trail is aligned to promote a diversity of experiences while reducing the risk of flooding.
The Hayward Shoreline Interpretive Center is protected in place with interim levee raising and future adaptation could occur through the elevation of the building itself. Its location within a marsh maintains a direct connection to shoreline ecosystems. The San Lorenzo Community Park is also protected in place, but vulnerable to potential groundwater emergence.
Two alternate configurations are outlined below in two areas that may require additional flexibility to align with ongoing projects and permitting constraints.