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Reverse Osmosis


The Town of Stonewall is pursuing a regional water project with the RM of Woodlands for the communities of Warren, Woodlands and Stonewall.   A portion of the funds for this project have been made available through the Investing in Canada Infrastructure Program.

The two municipalities are working together with Manitoba Water Services Board and Stantec Engineering to complete further study and design for the project.   Additional information regarding financial and environmental impacts, as well as frequently asked questions will follow in the weeks to come based on the results of the study.

The type of water treatment process being considered for the regional project is Reverse Osmosis (RO).  



Reverse Osmosis is a water purification process that uses a membrane (synthetic lining) to filter out unwanted particles such as contaminants and sediments like chlorine, salt, minerals, and dirt from drinking water. In addition to removing contaminants and sediments, Reverse Osmosis can also remove microorganisms – which you certainly do not want to drink. It gets water clean down to a molecular level, leaving only pure H2O behind.


Reverse Osmosis (RO) is a process that helps clean water by removing impurities and hardness from raw water making it safe to drink. It works by applying pressure to push the water through semi-permeable membranes (Membrane treatment unit) that trap particles and minerals leaving behind clean water. A by-product of reverse osmosis water treatment is reject water. This is the portion of the flow that does not pass through the RO Membrane Treatment Unit, and therefore is not included in the municipal water supply to residents.

Water that has gone through the RO process can become to aggressive which can cause issues with plumbing and appliances. To prevent aggressive water, the system that will be created for our community will include by-pass and blending. By-pass means that some of the raw water is allowed to skip the reverse osmosis process so it can keep its natural minerals. Blending is when the RO water is mixed with by-pass water. The blended water is then post treated with small amounts of sodium hydroxide (NaOH) and chlorine (Cl2). The result is balanced, clean, and healthy water that tastes great.