Backflow Prevention

Protecting Our Water System

Water normally flows from the public water system into your home or business, but backflow is the "backwards flow" of water from private plumbing systems into the public water system. Backflow can carry harmful contaminants and bacteria into the public water system, which can lead to illness, injury, and in some cases, death.  

Montgomery County Environmental Services is responsible for protecting the public water system from backflow and ensuring the safety of our public drinking water supply. Since 1993, our department has required the installation of backflow devices on commercial and residential water services that pose a potential hazard or threat to the public water system. This helps to minimize health risks and ensure the safety and purity of our drinking water.

Installing Backflow Prevention Devices

Our department requires commercial and residential customers to install a testable backflow prevention device when their plumbing installations pose a hazard to the public water system. This device prevents water from flowing backward into the water supply.

All backflow test results must be submitted through the Online Backflow Test Entry System. Testers must be certified through the Ohio Department of Commerce and approved by Montgomery County Environmental Services to use the online system. Contact 937-781-2631 to become an approved tester.

A few examples of businesses and plumbing situations that require backflow prevention may include:

  • fire sprinkler systems
  • lawn irrigation systems
  • customers with irrigation and deduct meters
  • medical facilities, laboratories, and mortuaries
  • commercial, industrial, and manufacturing facilities
  • restaurants
  • hair and nail salons
  • automotive repair shops
  • swimming pools

Customers must install and maintain the required backflow prevention device. Failure to do so poses a threat to the public water supply and may result in water service being disconnected.

Required Annual Testing of Devices

After a backflow device is installed, it must be maintained. A backflow device must be tested by a backflow-certified plumber (every 12 months) to ensure that the device is still in good working order.

Click this link to view our permits & plumber's resources page

If you are a tester and you would like to be registered to use our Tokay Portal, please send a copy of your test kit calibrations and your Ohio Backflow License to [email protected].

Please send all recertifications of your devices and license updates to [email protected].

All replacement devices must have a permit pulled. This will update the location in our Tokay database, allowing future test submissions to be entered. If a serial number is not found in our system, we will require a permit to update our system.

Backflow Prevention Regulations