Uni-directional Flushing Program


Municipal Office

395 Mulock Drive P.O. Box 328 Station Main, Newmarket, Ontario
L3Y 4X7

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​​The Town conducts a Uni-directional Flushing (UDF) Program each year. This process is considered to be one of the best ways to preserve high water quality and maintain the reliability of the water distribution system.

The UDF method of cleans the water mainlines through a network of flushing sequences with the water being discharged from a fire hydrant. A UDF program involves closing valves in a specific sequence to create water movement in one direction while opening specific hydrants at the end of that sequence. This technique allows higher water flow velocities by isolating certain sections of water mains. The higher water velocity allows for better scouring of the pipes and will use 40% less water in the flushing process than conventional flushing methods. Flushing pipes at higher velocities will dislodge and remove mineral deposits, biofilm and sediment that accumulate in the water mains.

In most cases, customers will not notice any changes to their water delivery during the UDF process. However, in some instances, homes may experience a temporary slight drop in water pressure and/or discolouration in cold water. There should be no disruption in service.

Due to varying rates and directions of flow in the water distribution system, our customers may experience a slight discolouration in their water, which at times in unavoidable. Under most circumstances, you can run your faucets for a short time after the testing is completed and the water should clear at your residence. Discoloured water in itself does not pose a health hazard, however if the water does not clear up after running your tap for a few minutes please contact Customer Service at 905 895-5193.

View our uni-directional flushing graphic below for more information on how uni-directional flushing works! 

Unidirectional Flushing Graphic.jpg