Alleviating Flood Waters.

According to the 2018 National Climate Assessment Report, sea level rise has already increased the frequency of high tide flooding by a factor of 5 to 10 for several U.S. coastal communities like the neighborhoods adjacent to the Bayfront Canal and Atherton Channel. These communities are subject to annual flooding as they are located in the downstream part of the watershed. Flooding is associated with high tides coinciding with storm events which prevent the canals from draining into the San Francisco Bay.

Climate change creates new risks and worsens existing vulnerabilities in these flood-prone communities. This presents growing challenges to public health, safety, and quality of life.

The proposed improvements would divert water from the affected area into the South Bay Salt Pond Restoration area. This project would assist in protecting people and property from flooding, mitigate flooding impact, improve stormwater quality, and help protect the San Francisco Bay.

Proposed Project Location:
Entrance of the Bedwell Bayfront Park
1600 Marsh Road, Menlo Park, CA 94025


We would like to thank everyone who attended our community meetings where we discussed:
  • What steps San Mateo County, in collaboration with Redwood City, the City of Menlo Park and the Town of Atherton, have been taking to improve community health and safety
  • A new project that will help reduce flooding in the neighborhoods and business centers near the Bayfront Canal and Atherton Channel
  • Concerns and feedback about the flooding issues in your area

If you couldn’t make it to any of our meetings and have any questions or concerns, please contact us here.

Past Residential Community Meetings:

6/1 @ 10AM, 6/20 @ 7pm and 6/22 @ 10 AM
Meeting location: PAL Community Center
3399 Bay Road, Redwood City, CA 94063. 

Past Business Community Meeting:

Tuesday, June 18th at 4 PM
Meeting location: Deerfield Realty
3715 Haven Avenue, Menlo Park, CA 94025

PowerPoint Presentation from meeting

Business Community meeting on June 18
Community meeting on June 20


Diverting Water Underground

This project proposes installation of two underground pipes (shown in yellow below) that extend from the Bayfront Canal at the upstream side of the existing tide gates to a new outlet at the adjacent South Bay Salt Pond Restoration area. Part of this project would also involve installing a trash capture device (2) to prevent debris and litter from entering San Francisco Bay. A six foot chainlink fence (3) separating the tide gate structure (1) from the road will also be added to ensure public safety.

Proposed Improvement diagram


Collaboration. For the good of the community.

San Mateo County is collaborating with Redwood City, the City of Menlo Park and the Town of Atherton to develop projects that provide flooding relief in the low-lying communities adjacent to Bayfront Canal and Atherton Channel junction. The proposed underground pipes are the first of a series of efforts to reduce the impact of flooding in the region and provide benefits such as:

Heavy rains combined with high tides can lead to flooding and lots of money to repair damaged homes, businesses, and properties. The sewage overflow, debris, and unknown contaminants in flood water can expose people to injury and perhaps even illness. The Bayfront Canal and Atherton Channel Flood Management & Restoration Project aims to reduce these outcomes and help protect both people and property from flooding.


With the threat of sea level rise and climate change at our doorsteps, it’s vital that we take steps to mitigate flood impact now rather than later. Mitigating flood impact now will help ensure a more resilient community for years to come.


The new diversion structure that is part of the project construction will feature a trash capture device which will catch any floating debris and prevent trash from going into the Bay. This design will help protect the water quality of the San Francisco Bay which is crucial to keep both people and wildlife safe.


This project is currently in the design phase and has obtained a Prop 84 construction grant of $1.135 million. The County and its collaborators are working hard to push this project forward. Below is a chart of the project history and progress.

FALL 2016

Flood Resiliency Program Started by San Mateo County


Agency and stakeholder meeting that initiate change

FALL 2017

Memorandum of understanding signed and Bayfront Canal and Atherton Channel Flood Management & Restoration Project kicks off


Project developed

FALL 2018

Pursue grant funds


Develop final design and begin environmental process


Advertising for bids and pre-construction meeting


Construction begins


We want to hear from you!

For more information, to ask questions, or voice your concerns, please contact Erika Powell, Flood Resilience Program Manager in San Mateo County at epowell@smcgov.org.