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Newsletter – March 2019

Upcoming Public Meetings on the Wastewater Treatment Plant

Residents of San Mateo are invited to attend three upcoming meetings to learn more about the Wastewater Treatment Plant Upgrade and Expansion Project, which is anticipated to begin construction this summer.

  • Tuesday, March 26: 7 p.m. Planning Commission, Public Hearing on Wastewater Treatment Plant Planning Application Modifications, Council Chambers, 330 W. 20th Avenue, San Mateo
  • Monday, April 15: 7 p.m. City Council, Public Hearing on Wastewater Treatment Plant Planning Application Modifications, Council Chambers, 330 W. 20th Avenue, San Mateo
  • Thursday, May 2: 6 p.m. – 8 p.m. Wastewater Treatment Plant Neighborhood Meeting, LEAD Elementary School, LGI Room, 949 Ocean View Avenue, San Mateo. At this meeting, Clean Water Program staff will provide a brief informational presentation, followed by a question-and-answer session.

Draft Environmental Impact Report: Underground Flow Equalization System

Map of meeting location.The public is invited to review and comment on the Draft Environmental Impact Report for the Underground Flow Equalization System, formerly called the In-System Storage Facility. This project is part of the City’s 10-year program to improve and repair the aging sewer collection and treatment system, and prevent sewer system overflows during heavy rains that threaten the health of city streets, beaches, and waterways, including the San Francisco Bay. The project would be located in the eastern portion of the San Mateo County Event Center Parking Lot.

The Draft EIR is available for public download and review.

Hard copies are available at City Hall, the San Mateo Main Library, and the Hillsdale Branch of the San Mateo Public Library.

You are invited to learn more about the environmental impacts covered in the Draft EIR and provide verbal comments at the April 9, 2019 Planning Commission meeting. The project is currently under review by City Planning for a Special Use Permit, which will also be discussed at the April 9 meeting.

The deadline to submit comments on the Draft EIR is May 7, 2019.

How to submit comments:

  1. Write to: City of San Mateo Public Works Engineering, 330 W. 20th Avenue, San Mateo, CA 94403, Attention: Clean Water Program
  2. Email:
  3. Speak at: April 9 Planning Commission meeting, 7:00 p.m. at City Council Chambers, 330 W. 20th Avenue, San Mateo

For more information on the EIR, and answers to frequently asked questions, please visit the Clean Water Program website.

For more information on the Special Use Permit, please click here.

Tuesday , April 9: 7 p.m. Planning Commission Study Session on Underground Flow Equalization System project and Draft Environmental Impact Report, Council Chambers, 330 W. 20th Avenue, San Mateo

North Idaho Sewer Rehabilitation Project Set To Begin

Map of project location.The Department of Public Works is replacing existing sewer pipes with larger pipes in several areas throughout San Mateo. This work will increase the capacity of the sewer system and reduce sewer overflows that occur during storms.

Using hydraulic modeling technology, our engineers identified the sewer pipe in North Idaho Street as being in need of upsizing. The North Idaho line is a primary line that moves flow from the north end of San Mateo to the wastewater treatment plant. The project will enlarge approximately 663 feet of 15-inch pipe to new, 24-inch pipe. This upgrade was found to be the most cost-effective solution, and one that minimized disruptions to the community.

Cratus, Inc. has been contracted by the Clean Water Program to perform this work.

The map below shows the project location. The work in North Idaho Street is currently estimated to take place from mid-March to mid-April 2019. However, this schedule may change.

Parking on North Idaho Street between Monte Diablo Ave. and Tilton Ave. will be affected for the duration of the project during work hours. “No Parking” signs will be posted in these areas 48 hours in advance of work. We ask that residents park their vehicles outside the work area prior to 7:30 am when work is being done on the street.

Thank you for your patience and cooperation as we complete this important project!