Orthophosphate FAQs

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What is orthophosphate?

Orthophosphate is an odorless, tasteless, substance that creates a protective barrier on plumbing surfaces to reduce the release of lead in drinking water from all sources, including lead service lines and plumbing. It is the industry standard for treating lead corrosion in municipalities all over the world and in Canada, and has been endorsed by Alberta Health Services and Alberta Environment and Parks.

Why do we need to add a lead inhibitor to the water if there are no known lead pipes in Leduc?

This is not a City of Leduc decision. EPCOR, who supplies water for much of the Edmonton region, is adding a orthophosphate as a lead inhibitor to their water to help mitigate any lead in Edmonton’s pipes, service lines, in-home plumbing, old solder and brass fixtures, which have the potential to exceed Health Canada’s proposed guideline. Leduc’s water will have the orthophosphate because we are an EPCOR customer. Note that the City of Leduc conducted a water sampling campaign in Leduc in 2021, and did not identify any lead that exceeded the guideline.

Are there any health effects related to orthophosphate?

Adding a lead inhibitor (orthophosphate) has no negative effects on health. It is commonly used by water utilities across North America and the United Kingdom to prevent lead from entering into drinking water. Phosphate is naturally present in food and is a common additive to beverages. In fact, you would have to drink 104 glasses of tap water to match the phosphorus in one banana.

Is there a difference between orthophosphate and phosphate?

Orthophosphate is a member of the phosphate family. Orthophosphates are small molecules, formed from the smallest and most basic form of phosphorus and are added to processed foods and naturally present in many foods.

Do I need to do anything after orthophosphate is added?

No, residential customers can continue to use the water as they normally would. There is no action necessary once orthophosphate is added. The water will remain safe to drink.

Commercial customers that use the water for manufacturing, food processing, petrochemical production, or commercial cooling and heating, may need to make adjustments to their processes.

What is the timeline for implementation?

Orthophosphate will be added beginning in Dec. 2022. The concentration of orthophosphate will begin at 0.9mg/L as P. EPCOR will monitor and, over time, optimize the concentration. Over approximately one year, concentrations may fluctuate. EPCOR anticipates that after the implementation and optimization phase, concentrations will remain stable with possible slight adjustments season to season.

How can I prepare my business for this change?

We are providing advanced notice of these changes to allow businesses adequate time to identify potential impacts on their processes and equipment. Some business areas that may be affected include:

  • Production and Water Treatment: The addition of orthophosphate may affect reverse osmosis and other water treatment systems. EPCOR recommends that you contact your process equipment consultants or suppliers to complete an assessment in advance of December 2022 to determine if you will need to make any required adjustments prior to orthophosphate implementation.
  • Heat Exchangers and Cooling Towers: Orthophosphate in the water may change the type and amount of precipitate that deposits on commercial heat exchangers and cooling towers. Companies may need to adjust their chemical treatment to account for the change in phosphate levels. It is recommended that companies contact their heating and cooling supplier, water treatment chemical provider or process consultant to discuss the need for adjustment to your heating and cooling system.
  • Boilers: The impact of orthophosphate on boilers is expected to be minimal. Many customers already add phosphate to precipitate calcium and/or as a tracer in their boiler system. For this reason, companies already adding phosphate may benefit from the implementation of EPCOR’s Enhanced Lead Mitigation Strategy. Companies that already add phosphate may need to adjust their dosage levels accordingly.

There may be other processes within your business that we have not identified that may be impacted by the addition of orthophosphate to the municipal drinking water. We recommend that you discuss these changes with a consultant to determine if there is an impact to your water process.

Who can I contact with questions? 

Please visit epcor.com/ortho to learn more, and contact EPCOR with any questions about the orthophosphate addition. 

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