Take Pride in Markham’s Drinking Water
– it meets and exceeds all Ontario related Health Standards and it’s yours to enjoy!
The water coming from your tap undergoes extensive treatment, filtration and continuous testing to ensure it meets all standards under the Ontario Safe Drinking Water Act, 2002. In this section you can learn more about water testing in Markham, access water quality reports, and get answers to some Water Quality FAQs.
Safe, clean drinking water is essential to the health of Markham residents. Markham’s tap water meets or exceeds all water quality standards as legislated by the Ontario Ministry of Environment and Climate Change. Ontario’s Drinking Water Systems Regulation (O.Reg.170/03) requires all drinking water system owners to collect and test a minimum prescribed number of representative water quality samples for its Distribution System. The distributed water is tested for over 120 water quality characteristics, such as physical, chemical, organic, inorganic and microbiological parameters.
Markham conducts daily sampling and testing to ensure that the water delivered to your home is safe. Physical samples are taken from green sampling stations that are scattered across the City; we have more than 100 of these sampling stations. Every year Markham’s water undergoes thousands of health related tests to ensure it is the highest quality.
All water samples are tested at the provincially accredited York Durham Region Environmental laboratory in Pickering. Each sample sent to the lab is documented, tracked and rigidly tested in order to ensure compliance with Ontario Regulation 169/03 Standards for Water Quality.
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Annual Water Quality Report
Markham collects and tests water samples at 106 locations throughout the distribution system in compliance with the Ontario Drinking Water System Regulation 170/03. Sampling is representative of Markham’s distribution system and tested rigorously for chlorine residual, bacteria, trihalomethanes, nitrites & nitrates, lead, organic and inorganic compounds. The samples are collected by licensed City operators and analyzed by the provincially accredited York-Durham Regional Environmental Laboratory.
The City reports any adverse sampling results to the York Region Medical Officer of Health and the Ministry of Environment and Climate Change (MOECC) are immediately undertaking the necessary corrective action to rectify the situation.
The drinking water distributed to Markham residents in 2016 was of high quality. Read the 2016 Annual Water Quality Report (PDF) for complete details.
Annual Water Quality Reports
|2016 Annual Water Quality Report
|2015 Annual Water Quality Report
|2014 Annual Water Quality Report
|2013 Annual Water Quality Report
|2012 Annual Water Quality Report
|2011 Annual Water Quality Report
|2010 Annual Water Quality Report
|2009 Annual Water Quality Report
Copies of these or earlier reports are available by calling 905-477-5530 or can be picked up at the Waterworks Department, at 8100 Warden Avenue, Markham or at the Contact Centre (Civic Centre), at 101 Town Centre Boulevard, Markham.
Ministry of the Environment
City of Toronto
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Community Lead Testing Program
Prior to 1953, lead was used as service line material for residential houses. Houses built after 1953 used copper, and more recently, PVC plastic for water service lines. To date, all known lead service lines in Markham, from the municipal watermain up to the property line, have been replaced.
Ontario Regulation 170/03 requires all municipalities to test drinking water for lead content. The Ontario Drinking Water Standard for lead is 0.010 mg/L. Water with lead content below this concentration Standard does not represent a health hazard.
As required by Ontario Regulation 170-03, Markham began testing residential water samples in December of 2007. By spring of 2011, after 16 rounds of lead water sampling, over 1400 samples were sampled and tested for lead. These samples were on a volunteer basis from various locations throughout Markham, targeting the older areas of Markham.
All lead test results were all well below the Ministry of Environment and Climate Change (MOECC) Drinking Water Quality Standards for lead of 0.010mg/L. As a result in fall of 2011 the MOECC granted Markham regulatory relief from community lead sampling.
Even though regulatory relief from lead sampling was granted by the MOECC, Markham is still committed to ensuring the highest quality of water and still takes 20 system lead samples annually. To date, all known lead service lines, from the municipal watermain up to the property line, have been replaced. However, there may still be private service lines from the property line to the house that are made of lead or contain lead. Similarly, the internal plumbing of a building may also still contain lead pipes. Should a resident suspect that their home has lead plumbing, they should contact a plumber. Should a resident suspect that they are connected to a lead service line, they may contact the Waterworks Department at 905-475-4862.
Markham Waterworks Department
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Well Water Testing
If you have a private well and would like to get your water tested, please visit York Region's Safe Water Program for more information.
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Toronto Corrosion Control Plan
Water supplied to the City of Markham customers is provided by the City of Toronto. This water is delivered to Markham through City of Toronto watermains. The same water that is delivered to Toronto customers is delivered to Markham customers.
The City of Toronto has some old neighbourhoods with old water services that contain lead. So, the water in this service line can absorb some of this lead and delivers water with elevated lead levels to the customers. In Markham we do not have such services and as a result do not have this problem. We know this because we conducted thorough testing in peoples' homes and we did not find elevated levels of lead.
The solution to this is service replacements or some form of corrosion control. The Ministry of the Environment (MOE) mandated the City of Toronto to prepare a Corrosion control Plan (CCP) to reduce lead concentrations in their drinking water systems. Toronto's CCP includes phosphate dosing at its water treatment plants as it has a long history of success for corrosion control in drinking water (Winnipeg, Chicago and Detroit). The phosphates form a protective coating throughout the entire network of distribution pipes reducing the corrosion of the lead pipes, therefore reducing the amount of lead in drinking water.
The implementation schedule for 2014 is as follows:
- R.L. Clark – March 31st
- Harris WTP – May 21st
- Island WTP – December 18, 2014
- Horgan WTP – December 3, 2014
Impact on Markham
It is expected that there will be an increase in the total phosphorous found in tap water up to 1 mg/L. Phosphorous is naturally present in food (e.g., milk, nuts and beef) and will have NO IMPACT on drinking water quality. The majority of users will not notice a change to their water; however some Industrial, Commercial and Institutional water users may be slightly affected. If you are an ICI customer that relies on municipal water for commercial heating or cooling, manufacturing or another use, it is suggested you contact your heating, or cooling supplier or process consultant to discuss whether slight adjustments are required.
Related Information Links
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Water Quality FAQs
Q: My water tastes or smells odd
A: Please call the Contact Centre at 905-477-5530 or e-mail email@example.com. A Waterworks staff member maybe dispatched to look into this issue.
Q: Why is the water sometimes discoloured? (Brown or White)
A: When a fire hydrant is opened, there is a large volume of water used which can stir up iron in the watermain. This causes water to be brown in colour. Cloudiness is caused when air becomes trapped in the water. This can happen when it travels through pressurized water pipelines, and the air remains trapped until it is released from your faucet. In either condition, the water is still safe to drink.
Q: What is the source of water supplied to Markham customers?
A: Markham’s water comes from Lake Ontario. It is treated and disinfected through facilities in Toronto and Peel Region.
Q: How safe is our water?
A: Markham’s water is safe. It meets the quality standards set by the Ontario’s Safe Drinking Water Act (SDWA), 2002. More information on water quality and treatment can be found under Markham’s Water.
Q: What is the method of disinfection used?
A: Markham’s water is chloraminated (use of chlorine and small amounts of ammonia) to destroy pathogens or disease causing microorganisms.
Q: How is the quality of the water assured? Is the water tested on a regular basis?
A: Water is tested at source treatment facilities on a regular basis. Markham Waterworks also collects and tests water samples in accordance with the Safe Drinking Water Act. Markham Annual Water Quality Report.
Q: What is Markham's water hardness scale?
A: Water hardness refers to the level of certain minerals in a water supply, typically calcium and magnesium carbonate. It has no adverse health effects. Markham’s water is considered hard at approximately 123 milligrams per litre, or 8.6 Grains per Gallon.
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