Project Overview

Our region’s drinking water originates from rainfall and snowmelt, and is naturally acidic, which accelerates the corrosion of copper pipes and plumbing fixtures. To address this issue, Metro Vancouver first implemented the Corrosion Control Program in the 1990s, and has been adjusting its water treatment process over the years to protect copper pipes and hot water tanks across the region.

The most recent change happened in June 2021, when Metro Vancouver further increased the pH and alkalinity using natural minerals to make the water less corrosive. This was an important step in this long-term program, and since then, Metro Vancouver has been monitoring the water quality through enhanced sampling and testing to analyze the changes across the regional water system and assess the effectiveness of the pH and alkalinity changes.

This change did not affect how our drinking water tastes or smells, and complied with the Guidelines for Canadian Drinking Water Quality.

  • What Changes Did Metro Vancouver Implement in 2021?

    In June 2021, Metro Vancouver increased pH to a target range of 8.3 to 8.5, and doubled alkalinity to about 20 mg/L (expressed as calcium carbonate) using natural minerals.

    This change had the purpose to help:

    • Reduce the release of copper from pipes in buildings caused by low pH in the region’s water
    • Reduce leaks in pipes caused by copper corrosion
    • Preserve the lifespan of pipes and hot water tanks
    • Reduce green stains on tubs, sinks, and grout

    Before implementing these changes, Metro Vancouver contacted applicable water users such as health care facilities and breweries to provide them with the opportunity to adjust their operations in advance of the change.

  • What Was Metro Vancouver’s Water pH Before the Change?

    Prior to the pH increase implemented in June 2021, Metro Vancouver was delivering water with a pH of 7.7, which was compliant with Health Canada’s guidelines.

  • What Is pH and Alkalinity?

    The pH scale ranges from 0 to 14, and determines whether a solution, such as water, is acidic or basic.

    Alkalinity is a measure of the water’s capacity to neutralize acids and bases to help maintain a stable pH level throughout the water system.

  • Resources




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Contact Us

Information Centre:
​Monday to Friday from 8:00 am to 4:30 pm
Phone: 604-432-6200
Email: Information Centre

After Hours Emergencies:

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