FAQ's

What is backflow?Cross-connections—commingling of the public water supply and contaminants/pollutants—play a threat to public health. Contaminants can enter potable water systems when the pressure of a polluted water source exceeds the pressure of the potable source. The action is called “backsiphonage” or “backflow,” or reversal of the hydraulic gradient. Documented cases of contamination to public water supplies have included sodium hydroxide from a chemical company as a result of a water main break, lethal herbicide chemicals from a holding tank and even human blood from a funeral home improperly draining fluids for embalming.
What causes backflow and potential cross-connections?Backflow can be the result of plumbing installations by individuals who are unaware of or disregard cross-connection dangers, or who utilize inadequate protection, such as single valves or other mechanical devices.
How do I prevent backflow?Backflow prevention devices can be installed to replace direct connections. Device selection is based on the degree of cross-connection hazard, as well as piping size, location, and other factors.
Who regulates backflow testing?Under the provisions of the Safe Drinking Water Act of 1974, the federal government established, through the Environmental Protection Agency (EPA), national standards for safe drinking water. States are responsible for enforcing the standards and supervising public water supply systems and sources of drinking water, while water suppliers must comply with the law and guarantee that water quality conforms with the EPA standards at the source and is delivered to customers without compromised quality through the distribution system.
How often do I need to get my commercial or industrial business backflow tested?According to the EPA, reduced-pressure principle backflow devices shall be tested and inspected at least semi-annually by a certified tester at the owner’s expense. Any backflow preventer that fails during a periodic test will need to be repaired or replaced. After repairs are completed, the device will need to be re-tested. If a backflow preventer fails testing in a high-hazard situation, it will need to be repaired immediately; if the failed preventer is not high risk, testing must be completed 30 days after a test date is established.
If I am a residential owner, do I need to get my home tested?Effective on the date when a given municipality accepted the EPA’s Cross-Connection Control Program, all new residential buildings are required to install a residential dual-check backflow device immediately downstream of the water meter. Installation on a retrofit basis is determined by the water authority at a cost to the homeowner.
Who sets standards for backflow preventers and testers?The American Society of Sanitary Engineers (ASSE), American Water Works Association (AWWA), and the University of California Foundation for Cross-Connection Control and Hydraulic Research.
Source: EPA