Safe drinking water is essential. The primary responsibility of keeping the public water system free of contaminants lies with the Water Purveyor. Consumers -- whether commercial businesses, property owners or homeowners -- also have some responsibility to assure that contaminated water doesn’t flow back to the drinking water supply.
Public Law 99-339 (also known as the Safe Drinking Water Act Amendments of 1986) and state regulations require that water purveyors, plumbing inspection officials, health agencies and consumers avoid situations where water from unapproved sources or any other substances can potentially enter the public potable water system. Where it is probable, that a system or hazard may be created, by the water user, a backflow devise is required. This type of hazard is found in most commercial businesses or multi dwellings buildings.
A backflow device employs valves, vacuums and other features to prevent water that has entered a private water system from co-mingling with the main water supply. As you create a water demand the backflow valve opens, allowing the water to free flow to the required source. Once that demand is met and you no longer are using water the device closes and seals tightly. The water stops and is not allowed to pass back thru the backflow device, isolating the water from the public potable water system. The failure of a backflow can occur when the internal parts become worn or damaged and do not seal properly. For this reason the local water purveyor and State Law requires the annual testing of the backflow device. Testing is done by a licensed AWWA (American Water Works Association) certified tester and must be approved by your local water company to provide services within your jurisdiction. Once the test is complete, and the valve is in compliance, a certified test report will be given to you. It is important to maintain accurate records of the testing and repairs, available for inspection by water suppliers, health officials and other authorities, should they be requested.
How do you know if a backflow device is necessary? Plumbing codes for new construction or remodels will include any requirements for a backflow devise to be installed. Existing commercial buildings or multi dwelling building fall under the jurisdiction of your local water company. They will survey the site and determine if you need a backflow prevention device. City Ordinances are in place in each jurisdiction for the size, type and the location of valves that are required.
For the installation of a backflow device you should rely on a professional, someone who knows the requirements of the specific water jurisdiction where you are located. Your local Water Company will typically have a list of certified testers that are licensed, experience and have met all of their requirements to test, repair or install backflow devises within their district; this is known as an Approved Testers List. .