Sudbury seems to have a high level of non-revenue water (NRW) compared to other cities. Shouldn't more effort be made to reduce leakage in the city?

    Firstly, not all NRW is leakage.  NRW also includes: unbilled consumption, unauthorized consumption, and metering inaccuracies/data handling errors.  One of the recommendations in the City of Greater Sudbury’s (CGS) 2021 Water Efficiency Strategy is to determine the Economic Level of Leakage (ELL) for all the CGS water systems. No water system is without at least some leakage and, of course, it cost money to find and repair leaks. Large leaks can waste large volumes of water and also cause significant damage to roads and properties; however, most systems experience only a few large leaks each year. Most systems also have a larger number of small leaks that don’t cause damage and simply infiltrate into the ground. Finding and repairing very small leaks can cost the City far more money than it would save by stopping the leak. By determining the Economic Level of Leakage or ELL of a system, a water agency can determine the minimum level of leakage they should tolerate in their system. Simply put – the ELL is the level of system leakage where the total cost to the CGS is at its lowest, i.e., where the cost of water lost through leakage equals the cost of implementing the leakage control measures (see Figure below). By determining the ELL, the CGS can determine if it would be economically beneficial or not to increase their leakage mitigation efforts.

    Why is it that when we use less water our water rates are higher?

    The CGS, like most cities, divides the total cost of operating its water system by the total number of mof water it sells to its customers each year.  Since approximately 90% of the costs of treating and distributing water are fixed, e.g., salaries, taxes, pensions, etc., the cost to the City remains almost the same even when demands decline.  So, when water demands decline, the cost of operating the water system is divided by fewer m3 of water and the cost per m3 increases.   Fortunately, even though the cost per m3 increases, customers that have reduced their demands might see little or no increase in their water bill.

    How can residential customers determine if they are efficient or not?

    The information you need can be found on your water bill.  The average residential customer is the CGS uses about 163 litres per capita per day (Lcd) and you can calculate the Lcd rate in your home by dividing the volume of water you used during the last billing period (listed in cubic metres or m3) by the number of days in the billing period. Then multiply this volume by 1000 to convert it to litres. Then divide this number by the number of persons in your home. If the water demands in your home are significantly higher than 163 Lcd there may be a good opportunity for your household to reduce its water demands.

    How can I reduce water demands in my household?

    There are many ways to reduce your water demands.  Some of the most popular and easiest are:

    • Replace your older toilets with newer WaterSense-labeled models that flush with only 4.8 litres of water or less.
    • Check for toilet leaks by adding a few drops of food colouring to the water in the toilet tank but don’t flush the toilet.  Check the water in the toilet bowl after 10 minutes or so and, if you see the colour in the bowl, you have a toilet flapper leak and should replace the flapper.
    • Replace your older clothes washers and dishwashers with new ENERGY STAR labeled models.
    • Replace your older shower heads with new WaterSense labelled models that use 5.7 litres per minute or less.
    • Never let the faucet run when you are not using it.
    • Make sure to only wash full loads in your clothes washers and dishwashers.