Calgary Cross Connection Services
What is backflow?
It essentially means the flowing back of water or reversal of the normal direction of water flow in either the Water System or a Customer’s Plumbing system into the public domain or water source. This moving water generally happens in residential neighborhoods with our cross connection valves. As one family opens a tap the water moves towards their tap but as another family opens their water they could be drawing more flow or possibly a fire hydrant is in use.. This can reduce your flow or even cause it to completely stop and suck air in through your faucet. This is only an extreme case example. However water will flow where ever it's needed most.
What actually happens?
Water flows from the public line into your home everyday. The average person in Calgary consumes 6,500 litres of water per day. The City of Calgary provides the cleanest water possible however you may have construction on your street or maybe a water main break. This can bring contaminated water in to your home. Or maybe you use a laundry sink with a hose attached. Maybe your child or pet soiled some clothing and you were filling the laundry tub up with some soiled clothing in the laundry tub with a hose attached to the faucet. This hose is now contaminated in soiled water. If you had a back flow situation this soiled water should now be in your piping system. Maybe you left for the day to go to work the bacteria is in your pipes breeding and now your home has a back flow situation where that water goes in to other homes in the neighborhood. This is why the cross connection program exists. There are some situations worse than others. Boiler make up water. Chemicals from the boiler attached to your water supply. or Outside irrigation water attached to your home supply, or maybe you're in a condo with 5 other units also attached. Maybe one of the units has a handyman mechanic or painter with a cross connection issue.. Our job is to asses each building and reduce the risk to the residence as well as near by buildings.
Certified Testing Procedure
If you received a letter, you need to have your cross connection device tested by a certified tester who is registered with the City of Calgary. In order to pass the test, it must meet the following criteria:
The Device Must Be appropriate to the Static Pressure of the line it is installed on
The First Shut Off Must Close
Check Valve 1 must close tight in the direction of flow
Check Valve 2 must close tight in the direction of flow
The second Shut Off Must close
In addition, the device must also be installed as per AWWA recommendations. AWWA stands for the American Water Works Association which is recognized as North America’s most prominent water inspection association. An improperly installed device can result in the immediate failure of a device both in terms of operation and testing.
