It is essential that all equipment for operating and maintaining the distribution system has regular use and testing to ensure that the equipment doesn’t seize up or malfunction. By having a schedule for exercising and maintaining all equipment associated with the water system, an operator can be confident that the system can continue to function during emergency events (water main breaks, etc.), repairs, or when routine maintenance is done. For example, by exercising a backup generator, the operator can be assured that it will not fail during a power outage. By exercising valves and hydrants, the operator can be assured that there won’t be interruptions in water flow during emergencies.
Timing of Maintenance
Valves should be evaluated and exercised at a minimum of once per year.
Hydrants should be inspected and flushed annually (preferably, twice per year, in the spring and fall) and the inspection should include flow tests and checks for leaks, rusting and damage.
Backup generators should be tested each month.
Pumps should undergo maintenance as per the manufacturer’s recommendation.
Dead end mains should be flushed on a routine basis to maintain water quality and at least once per year (in some cases, it may be suitable to install an automatic flushing system)
Water reservoirs should be evaluated annually and cleaned every 3 to 5 years, based on sediment collection on the bottom.
An Easement or Right of Way (ROW) is a strip of land on private property that acts as a corridor for water mains, sanitary sewer pipes and/or storm sewer pipes. With an easement, a legal agreement exists between the landowner and the water purveyor to provide 24/7 access for operating, maintaining or repairing any component within the easement that requires attention. The minimum width of a ROW is generally 3 metres; however, the width must be able to comfortably accommodate excavating equipment and vehicles that may be needed to repair water main breaks.
Leak Detection & Water Loss
Most water systems experience approximately 10% leakages and/or unaccounted water use. This may be from water main leaks, unaccounted water use from a property (running toilet or hoses), or illegal use of a fire hydrant.
Leaks can occur from corrosion, weakened joints or fittings, as well as damage to a water line, valve or other component. If unresolved, the leak can cause subsidence and/or sinkholes when the soil around the pipe is eroded. The pressure loss from the leak can also allow the intrusion of contaminated water into the distribution system (backflow).
Not only will a metered water system conserve water, it will make it easier to locate a water leak. Initially, leaks may be identified by observation of damp spots, seepage, or subsidence in the area surrounding the leak. Pressure drops (indicated by tests) can also indicate a leak in the distribution system. When an operator suspects a leak in the distribution system, qualified personnel can use leak detection devices to pinpoint the leak. Most leak detection instruments are listening devices (electrical or mechanical geophones) that are used to listen to buried water lines from the surface.1 Valves can be opened or closed as needed to isolate that part of the distribution system where the leak occurred so that repairs can be made.
Water metering is a user pay system that allows the water usage at each property (service connection) to be monitored on a continuous basis. Users are charged only for the amount of water used, allowing lower volume customers to realize savings. Water metering also enables leaks to be detected earlier.
For unmetered water systems, water users pay a flat rate regardless of the amount of water they use. For example, a property with a swimming pool, irrigation system, or greenhouse would be charged the same fee as a dwelling that only uses water within the home.
The cost/benefit of establishing a metering program will usually depend on the size of the water system. Compared to small systems, large municipal systems can benefit from an economy of scale with lower cost averages for the installation and maintenance of the meters. For a small system, it may be more beneficial to maintain a flat rate unmetered system while encouraging responsible water use.
1Leak detection in water distribution networks: an introductory overview by Samer El-Zahab & Tarek Zayed.
Guidance on Monitoring the Biological Stability of Drinking Water in Distribution Systems, Health Canada, Feb. 2022
Maintaining Distribution System Water Quality, Government of Nova Scotia
Drinking Water Chlorination Facts, HealthLinkBC, June, 2022
Drinking Water Chlorination, Health Canada
Water Distribution System Operation & Maintenance, 7th Edition, A Field Study Training Program, California State University, Sacramento California, 2018.
Water Disinfection with Chlorine and Chloramine, Centers for Disease Control and Prevention, USA
Drinking Water Protection Act: Drinking Water Protection Regulation, Province of BC, Reg. 200/2003, including amendments up to B.C. Reg. 122/2013.
Small Water System Guidebook, BC Ministry of Health, Feb. 2017