Cross Connection Control Program (CCC)
The Municipality protects, treats and delivers safe drinking water, but our responsibility does not end there. We are required by Nova Scotia Environment (NSE) to enforce the installation of Backflow Prevention (BFP) Devices on water service lines where there is greater potential for backflow.
The Municipality’s first step to our Cross Connection Control Program is monitoring the installation and maintenance of BFP devices to minimize risk of a potential contaminant entering the distribution system from a customer’s premise through backflow and help protect the public’s safety by preventing drinking water contamination.
Backflow Prevention (BFP) Devices
The type of BFP device is based on the degree of hazard that the specific location represents to the drinking water supply. A Backflow Prevention Device Application Form must be filled out by a professional engineer or certified plumber, in accordance with the CSA B64.10 and CSA B64 series, to determine the degree of hazard.
|CSA Standard No.||Type of Device||Minor Degree of Hazard||Moderate Degree of Hazard||Severe Degree of Hazard||Device Under Continuous Pressure|
|B64||Reduced Pressure Principle Assembly (RP)||X||X||X||Yes|
|B64||Double Check Valve Assembly (DCVA)||X||X||–||Yes|
|Degree of Hazard||Definition|
|Minor (MH)||Any cross connection or potential cross connection that constitutes only a nuisance and that results in a reduction in only aesthetic quality of the water.|
|Moderate (MoH)||Any minor hazard (MH) connection that has a low probability of becoming a severe hazard.|
|Severe/High (HH)||Any type of cross connection or potential cross connection involving water that has additives or substances that under any concentration, can create a danger to health.|
Testing and Maintenance
It is the customer’s responsibility to ensure that all backflow prevention devices must be tested upon installation and annually thereafter. If the assembly fails its test, maintenance or repair is immediately required. The assembly must be retested immediately after any repairs, maintenance, or when the assembly has been removed, reinstalled or changed locations.
Backflow prevention assemblies must be annually tested, at minimum, because they have internal seals and springs that are subject to wear or fatigue.
At Your Annual Backflow Prevention Device Test
East Hants Rules and Regulations specify that the Municipality may give notice to correct any non-compliance with the Cross Connection Control & Backflow Prevention section of the schedule. This includes the annual testing of BFPs. As a last resort in cases of non-compliance, the Municipality may suspend water service. We will always prefer to work with the property owner towards a solution, but backflow hazards will be taken seriously as they are potential risks to public health.
Thermal Expansion Awareness
It is important to address Thermal Expansion when installing backflow prevention devices to ensure effective operation of your water system.
- Thermal expansion: When water is heated, density decreases and volume increases.
- The increase in water volume must go somewhere.
- If the extra volume created by expansion overcomes the incoming supply pressure, water can backflow into the public drinking water system.
- BFP devices, pressure reducing valves and other one-way valves create a “closed system” during no-flow periods in the system.
- This solves the problem of backflow, but creates other issues.
- Thermal expansion in a closed plumbing system can cause maintenance problems and serious health issues:
- i.e. The build-up of unusually high pressure in a system causing pressure surges and/or the chronic or continuous dripping of a temperature and pressure (T&P) relief valve.
- i.e. Dripping faucets and leaking toilet tank ball cock fill valves
- i.e. When dangerous pressures are built up in a water heater, internal parts may fail such as the internal flues, fittings or water connections. If a flue way collapses, it can lead to the potential release of toxic gases, such as carbon monoxide into living spaces. Thermal expansion can also lead to a ruptured or distorted hot water heating tank and may void the manufacturer’s warranty.
- According to the National Plumbing Code 1995 (Section 6.1.11), “When a Backflow Prevention Device, Pressure Reducing Valve, or a Check Valve is required, protection against thermal expansion may be required.
- To accommodate the increase in pressure caused by thermal expansion within a closed water distribution system, one of the following should be installed:
- A suitable sized diaphragm expansion tank designed for use within a potable water system.
- An auxiliary thermal expansion relief valve (T.E.R. valve) conforming to CAN/CSA- B125, “Plumbing Fittings,” set at a pressure of 550 kPa or less and designed for repeated use.
- Other means acceptable to authority having jurisdiction.To prevent any damage to private property caused by thermal expansion, you are responsible to have a licensed plumber inspect your plumbing system to determine if there is a closed plumbing system.If so, you should have the plumber install an appropriate device to eliminate the problems that can occur because of thermal expansion.
- Failure to address this potential problem within your premises may cause damage to your water heater and/or plumbing system.