Watermain Flushing and Swabbing

Watermain Flushing

Watermain flushing (cleaning) is performed by certified water operators to ensure that distribution pipes are clean and safe and carry the freshest drinking water to residents and businesses.

It is performed by moving potable water through the pipes at high speeds and letting it out through fire hydrants until the water runs clear. Flushing removes scale and accumulated residue that has naturally built up in the watermains over time. No chemicals are used during this process.   Watermain flushing is performed across the Town as a routine maintenance activity and is also required when installing a new watermain or repairing a watermain break.

Watermain Flushing Frequently Asked Questions

How does the Town notify customers affected by the program?

Public Works department of the Town uses several methods to inform customers of planned watermain cleaning and possible discoloured water caused by the program. Notification is done by the following methods:

Information posted to the Town website and Social Media:

Will watermain flushing impact my water service?

Your water service will not be turned off, but there may be less water pressure.  We advise you to bypass any water treatment or conditioning devices because you may receive discolored water.

Can I use my toilet during the time that the watermain is being flushed?

Yes. You can use your toilet by pouring a pail of stored water into your toilet bowl to allow your toilet to manually flush.

What should I do after the watermain cleaning is done?

Run a hard-cold-water tap (preferably a laundry or bathtub tap with no screens) for approximately 10 minutes at the end of the day – each day that the flushing is scheduled for. This will clear any discoloured water left in the water line. Run the washing machine through a cold rinse cycle before loading laundry to prevent staining of laundry items.

Where does the sediment in the watermains come from? 

The sediment present in the watermains consists mostly of a combination of iron.  Iron oxides are formed when chlorine combines with the dissolved iron and manganese minerals naturally occurring in Alliston and Tottenham’s groundwater.  These oxides are heavy and will settle out on the bottom of watermain piping during periods of normal use.  The settled particles are stirred up to form discoloured (usually brown, red, yellow, or black) water when a larger demand i.e. firefighting or illegal water taking, for water use occurs or when maintenance is being performed, i.e. flushing.

Watermain Swabbing

Watermain swabbing involves scouring the watermain with a soft material shaped like a bullet. These swabs are injected at a hydrant and pushed along the watermain (by water pressure) to be removed further down the main through another hydrant.  As it passes through the watermain, it executes a scouring action on the sediment inside the watermain. The hydrants are left open until the water runs clear.  The procedure requires the water be turned off in a specific section to prepare for the swabbing.  During swabbing, the pressure will be reduced considerably and residents are asked not to use water for any purpose during this time. 

After swabbing is done, run the cold hard (unsoftened), and unfiltered water closest to your water meter until the water is clear.  If water remains discoloured after 10 minutes of flushing, please turn off the tap, wait one hour, and repeat the 10-minute flushing process.  If your water does not clear please contact the Town at 705-435-3900 Option 4.  Once the water is clear, turn on your water treatment and/or softening devices and flush each tap if necessary to remove the discoloured water from your piping.  The cost of flushing your pipes is minimal.  At current water and sewer rates, a customer in New Tecumseth pays approximately 4 cents for every minute that a tap runs.

Watermain Swabbing Frequently Asked Questions

How can I prepare before the watermain swabbing on my street begins?

Before watermain swabbing occurs on your street, it’s recommended to store water in a container in the fridge to use for cooking and drinking. You can also fill your bathtub with water for washing your hands or flushing toilets. Also, be sure to complete dishwashing, laundry, and other activities that require water prior to the watermain swabbing activity. Please turn your water softener and/or filters to by-pass or shut off the main water supply valve located next to your water meter. 

Can I use the water while the watermain on my street is being swabbed

Please refrain from using your water when your street is being swabbed.  Many people find it useful to turn off their main water shut-off (at the water meter) before swabbing begins to avoid any inadvertent running of the water - which may result in discoloured water/sediment being drawn into your internal plumbing.

How does the Town notify customers affected by the program?

The Town uses a number of methods to inform customers of planned swabbing areas:

What should I do if my laundry becomes stained by discoloured water?

If you are washing clothes and receive discoloured water, stop the cycle while the tank is full and wait until clear water is available to finish. If the spin cycle has finished, then keep the clothes wet and rewash them when clear water is available. If you wash your stained clothes using a commercial rust remover, then follow the directions on the rust remover label to avoid damaging your clothes.

Is flushing my pipes to remove discoloured water costing me money?

The cost of flushing your pipes is minimal.  At current water and sewer rates, a customer in New Tecumseth pays approximately 4 cents for every minute that a tap runs.