Water main cleaning program Frequently Asked Questions


Municipal Office

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

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​​​​​​​​​​​​Water mains are underground pipes that carry water from the source to your street and ultimately to the service pipes connected to your house. The goal of the Town of Newmarket's Water Main Cleaning Program is to minimize the occurrence of discoloured water and ensure customers receive the freshest water possible by removing accumulated material from the water mains.

The Town will be starting its Water Main Cleaning Program on Monday, May 8, 2017 and will be ongoing throughout the summer. Water main swabbing is one of the techniques the Town uses to clean the water mains. ​

What is water main swabbing?​​

Water main swabbing involves inserting a foam sponge – or 'swab' – into the water main through a fire hydrant. The diameter of the swab is slightly larger than the water main and it is pushed along through the water main using water pressure.  As it passes through the water main, the swab clears any sediment that has built up inside ​the water main.

Can I use the water while the water main on my street is being cleaned/swabbed?

Please refrain from using your water when your street is being cleaned/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's Water Department notify customers affected by the program?

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

  • Hand-delivery of notices to each affected residence at least 24 hours before the swabbing begins

  • Notices in The Era (Town Page)

  • Information posted on the Town's website​ and on social media channels such as Twitter and Facebook

  • Mobile electronic signboards in the neighbourhood​​​ that is undergoing maintenance that day

What should I do when the water main on my street is being cleaned/swabbed?

Before the scheduled operation begins, you should:

  • It is recommended that you turn off your water valve, located next to the water meter to prevent water use during this time

  • Fill a clean container with tap water for drinking and cooking (store in fridge)

  • Complete all dishwashing, clothes washing and other water-use activities

  • Fill your bathtub with water for use around the house (you may use a pail to transfer water from the bathtub to your toilet bowl to allow your toilet to flush)

During the period that swabbing is underway, you should:

  • Avoid using water for any purpose

After the swabbing has finished for the day, you should:

  • Run the cold, hard (unsoften) water tap closest to your water meter (usually located in the basement) until the water is clear.  Or, if your garden hose does not go through your softener, you can irrigate your lawn or garden until the water is clear. 

  • If the water remains discoloured after 10 minutes of flushing, please turn off the tap, wait 60 minutes and repeat the 10-minute flushing process again. If your water does not clear after two hours, please contact the Town of Newmarket for assistance at 905-895-5193.

  • If you experience lower-than-normal water pressure after the maintenance is complete, please verify if it is at just one tap, or throughout your home.  If it appears to be at one location only, try removing and cleaning the aerator (screen) at the tap and run the water until it clears. 

  • If you experience lower-than-normal water pressure or no water after the cleaning is complete, please call the Town at 905-895-5193.​

Can I drink the water?

Once the normal water clarity has returned, all normal uses can be resumed, including drinking the water.  ​

I am noticing a strange odour and taste in my water. 

The strange odour/taste in the water may be due to a non-pathogenic sulphate reducing bacteria (SRB) in the water system during water main flushing and swabbing. If you are experiencing a strange odour and/or taste in your water, please contact the Town of Newmarket at 905-895-5193.​

I noticed red/brown coloured water from the swabbing/flushing program flow into the stream, is that safe for wildlife?

 The red/brown coloured water is from iron that has built up in the water main. When conducting water main swabbing and flushing programs, the iron is removed and as a result you may notice discoloured water flow into the catch basin and into the stream.

Prior to the water flowing into the catch basin and stream, any chlorine residual is removed. While aesthetically unpleasing, the discoloured water presents no harmful effects to the wildlife in the streams. ​

How long will it take to clean the watermain on my street?

Generally, multiple streets identified will be completed within the scheduled day. Work is typically completed within 8 to 10 hours and includes set-up and teardown of the equipment. ​

How long will my water be shut off?

Staff will try to have water use restored within 8 to 10 hours. Generally, multiple streets within an area will be completed within the scheduled day. If there are any delays or extended disruptions, staff will notify residents immediately.

Why is the Town performing watermain cleaning again?

In order to ensure the highest quality of water for our community, Newmarket water and wastewater staff routinely performs watermain spring-cleaning programs to do a thorough cleaning of the watermains.

Some areas of the Town's water distribution system will need to be cleaned more frequently depending on the water age [HK1] and how fast the water is travelling through the watermains. When water is moving slower through the watermains, there is a higher potential of iron and sediment build-up, therefore a thorough watermain swabbing technique is required to clean the watermain. ​

I am a dialysis patient, what can I do?

Newmarket staff is aware of locations where dialysis patients reside and will personally visit the home to ensure the patient receives the watermain cleaning notice and make other arrangements that best suit the resident. If you are a dialysis patient and is unsure if the Town has your information, please give us a call at 905-895-5193. ​