Drinking Water Drinking Water Indicators Improving Drinking Water

Drinking Water Testing (Adverse Samples)

What Does This Mean?
Why Is This Important?
How Are We Doing?
Taking Responsibility - What You Can Do
We Must All Be Accountable – Improving Water Conservation and Wasting Less Water

What Does This Mean?

It means we’re constantly checking in order to ensure our water is safe.

Public health could be affected if the water we drink becomes contaminated and unfit as drinking water. To ensure results are reliable, multiple samples are tested at many locations along the route.

An unusual test result, called an “adverse sample” is immediately retested and additional samples are taken alongside. If the retest confirms the original result, it is described as “exceeding” the drinking water standard and further steps are taken to solve the problem. These further steps could include contacting the Medical Officer of Health and issuing a boil water advisory.

Over 120,000 samples are tested annually and those that are determined adverse, are immediately retested. In all cases, the further testing revealed that the additional samples met requirements and determined that the original adverse sample was caused by something else, not contaminated water.

Routine testing of the drinking water for contaminants is done at the two water supply plants at Lake Huron and Lake Erie. Further tests are completed as part of the City distribution system. All tests are in accordance with the Ministry of the Environment Drinking Water Standards.

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Why Is This Important?

The stringent testing procedures means we have clean, safe water.

Public health could be effected if the water we drink becomes contaminated making the water unfit for human consumption. The occurrences of contamination are more common with smaller water treatment facilities or for individual groundwater wells in the rural areas that supply individual households with their drinking water source. Since levels of contamination we are looking for are typically quite low, errors in the testing procedure can falsely lead to an adverse sample. The normal approach is to immediately resample and take extra samples to verify the results.

Increased awareness across the country of the sensitivity of drinking water to contamination has occurred since the tragedy in Walkerton, Ontario in 2000 when E.Coli made its way into the water system. New and updated legislation in Ontario since 2000 has further strengthened the checks and balances used to ensure the safety of our drinking water.

We test and re-test, just to be safe.  We are being proactive and responsible, understanding the need for safe, reliable water and it’s about keeping track of quality at every level.

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How Are We Doing?

â Staying The Same

London has the advantage of having a technologically advanced drinking water treatment system.

Our existing water system obtaining Great Lakes water has been in place since 1967. We have maintained a high standard of drinking water complying with all requirements throughout the 39 years since it was constructed. In the past 3 years, legislation changes mean comparisons prior to 2002 are more difficult to illustrate. Therefore, the chart starts at the first year since the new legislation; that being 2003.

City staff take 172 samples monthly, from 58 locations across the City, testing for microbiological indicators and chlorine residuals. In addition, between the quarterly and annual samples that are taken at 13 locations, analysis is performed for 137 parameters including organic and, inorganic parameters, pesticides, metals, and many other chemical indicators. Furthermore, chlorine residual is monitored continuously using in-line sampling probes at four locations within the distribution system, while turbidity and fluoride are also monitored continuously at one location.

The City of London has consistently met all requirements of the Drinking Water Standards.  At this high standard of excellence, it is hard to see where improvements in drinking water quality can be made. But we will continue to seek improvements.

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Taking Responsibility - What You Can Do

• Water is a precious resource – treat it with respect
• Ensure household special wastes are disposed of at the designated depot at the W12A Landfill site open every Saturday except statutory holidays.
• Conserve water where possible by using faucet aerators to reduce water used for washing hands and rinsing dishes
• Install low flow shower heads and low flow toilets to reduce waste water from your home
• Take a five-minute shower instead of a bath
• Turn the tap off when brushing your teeth; use a cup of water to rinse
• Do one load of dishes in a full dishwasher rather than several partial loads
• Use rainbarrels outside your home for yard work such as garden watering or car washing
• Consider sweeping your sidewalks clean instead of using a hose
• Water your lawn only when necessary (about 1 inch or 2.5 cm per week) and not in the hottest portion of the day when most water will evaporate. Remember to consider the amount of rain per week in your watering calculations.
• Group plants with the same watering needs together to get the most out of your watering time, or consider drought tolerant species. Alternative gardening techniques such as xeriscaping and water gardens can be used to reduce watering needs.

We Must All Be Accountable – Improving Water Conservation And Wasting Less Water  - Find Out More
 

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