Saint John using orthophosphate to stabilize leaky pipe scale

Trenching to install a new large water transmission main
Trenching to install a new large water transmission main as part of the Saint John’s Safe Clean Drinking Water Project. Photo credit: City of Saint John.

Saint John City Council in New Brunswick has agreed to use an orthophosphate treatment system to resolve problems that have occured after it switched over 5,600 water customers to a new reservoir last September.

The chemical treatment, which could cost more than $130,000, is not dangerous to consume and is commonly found in most baking ingredients. In a meeting late February, council said it hoped the system will begin to remedy the suddenly leaky and sometimes bursting corroded copper pipes of more than 200 residents who switched from surface to groundwater.

Some residents believe the harder water drawn from the aquifers have caused not only plumbing damage, but water heater problems, irritated skin and stained dishes. All of the problems have prompted a class-action lawsuit against the City on behalf of affected residents.

According to a statement by Saint John officials, the west water supply comes from aquifers deep below the ground’s surface at the site of the wellfield. As the water travels through the ground, it is naturally filtered through sedimentary rock and calcium-bearing minerals, which increases its level of hardness and the concentration of minerals. Three large wells collect the water before it is pumped to the South Bay Treatment Facility where it is treated and sent through the distribution system to homes.

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Following residents’ outcry, Saint John Water launched a research study in partnership with consultants CBCL Ltd. and Dalhousie University. The study includes an analysis of numerous different copper pipe samples from affected homes along with water from Spruce Lake, the previous water source, and the new South Bay Wellfield. The study is being conducted at the Centre for Water Resources Studies at Dalhousie University and initial results are expected within the next two months, with all results available in four to five months.

Watch a video presentation to city council on the water concerns of residents.

“We have been working diligently with water industry experts to analyze and test the collected samples and work towards a suitable solution,” said Saint John Water Commissioner, Brent McGovern, in a statement. “While we await results of the study, we have identified an opportunity to respond to customer concerns with a safe, immediate solution to mitigate copper pipe leaks.”

Saint John Water further stated that using the orthophosphate treatment system should stabilize the existing scale formation and corrosion on the copper pipes. The City will treat the surface water supply with orthophosphates at the new Loch Lomond Water Treatment Facility on the east side, when the Safe, Clean Drinking Water project is completed later this year. Orthophosphate is also applied to surface drinking water treatment in other local municipalities like Moncton and Halifax.

There will be no additional cost to customers for the treatment, as costs will be managed within the City’s water and sewerage utility operating budget.

The City’s ongoing Safe Clean Drinking Water Project aims to ensure good water quality that meets current and future water standards; correct deficiencies in the current water distribution system; and create adequate water supply for fire protection and customer use.


  1. This is something interesting.I found this article very informative . I am glad that I came across such an article. Great technology has been used here to stabilize the leaky pipe scale.You have very nicely explained about it in a detailed manner.Keep posting such article.

  2. We have technology to eliminate all chemicals and inhibit the scaling and rust. Our company; flowscience guarantees results or we buy back our products.


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