Local Advanced Water Purification System

Project typeSystem Improvements
Project value$66.8 million

Rendering of Advanced Water Purification System

Project Overview

This project will improve the quality of recycled water by reducing the Total Dissolved Solids (TDS). It will meet the City Council’s goal to reduce TDS in recycled water. This will encourage expanded use of recycled water for non-potable uses such as irrigation. The process will utilize microfiltration or ultrafiltration followed by reverse osmosis to reduce the level of TDS.

The Regional Water Quality Control Plant currently provides tertiary-treated recycled water to permitted users in its service area, mostly for irrigation. The current recycled water delivered has a TDS level of 700-800 mg/L. High levels of TDS are harmful to salt-sensitive plant species. In 2010, City Council adopted a goal to reduce the TDS level to 600 mg/L. In 2015, City Council adopted an Environmental Impact Report (EIR) for the Phase III Recycled Water Pipeline to South Palo Alto and Stanford Research Park. The EIR specifies that recycled water quality needs to be improved through additional treatment. In addition, there are approximately 40 potential recycled water users in the service area with their connection pending until TDS levels are lowered.

The Plant, in collaboration with Valley Water (formerly known as the Santa Clara Valley Water District) and the City of Mountain View, conducted an Advanced Water Purification System Feasibility Study in 2017. This study recommended microfiltration or ultrafiltration followed by reverse osmosis after comparing different water quality improvement options. The study also included evaluations of greenhouse gas emissions, storage requirements, facility sites, concentrate treatment options, and initial design and construction cost estimates.

This project was identified in the Long-Range Facility Plan (LRFP) which was completed in 2012.

To learn more about recycled and other non-potable water.

Scope of Work

Install membrane filtration, reverse osmosis and chemical delivery systems
Construct a reverse osmosis permeate storage tank
Construct a pre-engineered open-air building for the water purification system
Install a small prefabricated electrical building
Install yard piping for the recycled water
Install a water blending station in the existing administration building
Plant new landscaping to maintain a screened facility
Construct a new concrete screening wall

Public Impact

There will be temporary closures and rerouting of the walking path and bike lane on the southside of Embarcadero Road. There will be a traffic lane reduction on Embarcadero Road. Both impacts will be located near the water treatment plant. A new walking path will be constructed.

Project Milestones

Winter 2017 – Pre-design Complete
Winter 2019 – Approval of Regional Partnership between Palo Alto, Mountain View and Valley Water and Approval of EIR Addendum to proceed with the Local AWPS.
2021-2023 – Detailed design
Fall 2023 – City Council approved preliminary finance plan
Spring 2024 – City Council approved planning entitlement
Fall 2024 – Construction solicitation
2025-2027 – Construction phase
Winter 2027 – Startup and commissioning

Meetings

City Council Staff Report for Approval of Addendum to Environmental Impact Report November 18 2019.pdf(PDF, 3MB)

City Council Action Minutes Approval of Addendum to Environmental Impact Report November 18 2019.pdf(PDF, 79KB)

City Council Staff Report for Approval of Design Contract March 8 2021.pdf(PDF, 928KB)

City Council Action Minutes Approval of Design Contract March 8 2021.pdf(PDF, 639KB)

Architectural Review Board Meeting Packet November 2 2023.pdf(PDF, 48MB)

Planning and Transportation Commission Staff Report February 28 2024.pdf(PDF, 33MB)

City Council Staff Report for Record Land Use of Action May 13 2024.pdf(PDF, 11MB)