What is Unidirectional Flushing (UDF)?
EPCOR will be cleaning the water mains using a UDF approach. UDF simply means guiding water in a single direction through the pipes by systematically closing valves and releasing it through fire hydrants.
Will I be affected by water main flushing?
You may experience temporarily cloudy water or low water pressure for the duration of the flush in your area. Your water won't be turned off and you'll continue to receive uninterrupted water service to your home.
Your water remains safe to drink during this time.
Can I do anything about temporarily clouded water?
If you experience cloudy water, we recommend that you run your cold water tap for approximately three minutes or until the water runs clear. You should notice the water starting to clear after our flushing is complete.
How long will UDF take?
A drop in water pressure caused by UDF servicing can range anywhere from 15 to 60 minutes, with an average of approximately 25 minutes.
Will UDF servicing increase my water bill?
UDF servicing doesn't affect your water bill. You're only charged for water that passes through your meter and flushed water is emptied out of the distribution system well before then.
How does UDF work?
UDF involves the systematic closing of valves and opening of hydrants to create a single direction of flow. All that water flowing in one direction results in faster velocity and more turbulent flow, which means cleaner mains.
We flush from largest mains to smallest mains and the cleanest mains to dirtier mains. This ensures dirty water is not being pushed into clean pipes, and that the pressure stays high.
Why is flushing required?
Don't use any type of liquid lawn products that attach directly to your hose when your area is receiving UDF service. Due to the water pressure change, anything attached to your hose could be sucked into it and will end up in your water main, potentially contaminating your and your neighbours' water supply. You can learn more about this hazard on our
preventing backflow page
UDF is effective in:
- Scouring (scrubbing) of the inside of the pipe.
- Removing sediment, silt, and biofilm.
- Improving water colour.
- Improving turbidity (clearer water, less cloudy).
- Increasing chlorine residual.
- The opportunity for preventative maintenance on water infrastructure.
By pumping high pressured water through the pipes and releasing it through fire hydrants, we rid the mains of biological and mineral deposits and get the cleanest, clearest water to you.
Does UDF waste a lot of water?
Because UDF is more effective at getting the pipes clean, we're able to flush less often. And because the pressure and velocity used in UDF is so much higher than traditional flushing, we actually run the water for a shorter duration. Our flushing schedule is also designed to ensure that we never unnecessarily flush an area.