S.F. Bay to Highway 101

The SFCJPA’s first major capital project will complete design in the fall of 2012, and the public draft of the Environmental Impact Report will be released on July 30, 2012, with the Final EIR expected to be certified in October 2012. When constructed, the project will reduce flood risks in East Palo Alto and Palo Alto along a flood-prone reach of the creek downstream (east) of U.S. Highway 101 to San Francisco Bay. Additionally, it will reduce flood risks from Bay tides and 50 years of future Sea Level Rise within the creek in concert with the SFCJPA’s planned coastal levee system for the region.

This project will also provide the capacity needed for upstream flood protection projects being designed by the SFCJPA, significantly benefit the habitat of three endangered species in the area, and improve Bay trails and outdoor education opportunities.

In order to increase creek flow capacity from San Francisco Bay to Highway 101, we will:
• Widen the creek to convey a 100-year storm flow, coupled with a 100-year tide and 26 inches of Sea Level Rise;
• Excavate sediment that has built up over several decades and replace it with a marsh plain with higher value vegetation that is naturally more self-sustaining;
• Remove an abandoned levee to allow high creek flows into the Palo Alto Baylands north of the Creek, thus reinstating a natural connection to the Bay for the first time in over 75 years and reducing the elevation of water within the creek channel; and
• In the area confined by homes and businesses, construct floodwalls aligned to Caltrans’ Hwy. 101 bridge over the creek.

For a number of reasons this section of the creek is the first priority for the JPA’s flood management efforts:
• It is at very high risk of severe flooding from both fluvial (flows coming down the creek from the hills) and tidal sources;
• It runs through communities that have experienced considerable damage and dislocation from previous flood events;
• It is a necessary first step to providing comprehensive flood protection, as upstream projects cannot be built until downstream capacity has been increased; and
• Lowering the water surface elevation through this reach helps drain upstream areas and adjacent neighborhoods below sea level.
For these reasons and more, this initial project holds critical importance, both as a short-term flood protection measure with localized benefits and as a key piece of the JPA’s long-term comprehensive flood management strategy. Consequently, design of the SF Bay to Highway 101 project is on an accelerated schedule, with design and environmental review expected to be complete so that construction can begin in late 2012.  The Santa Clara Valley Water District and the San Mateo County Flood Control District have contributed funding for the design and environmental planning of the project, and the JPA has received a grant from the State Department of Water Resources to begin construction with local matching funds.