A Backflow Prevention Device, or Backflow Preventer, is used to protect potable water supplies from contamination or pollution due to backflow (the unwanted flow of water in the reverse direction).
When a water main bursts, pipes freeze or there is unexpectedly high demand on the water system, the pressure reduction in the pipe may allow contaminated water from the ground, from storage or from other sources to be drawn up into the system.
A backflow preventer is a safe guard for the supply line, blocking contaminated water from entering the system.
For information on municipal codes and regulations regarding backflow prevention devices, visit AustinTexas.gov
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