Cross-Connection and Backflow Prevention Program



Annual Testing of Backflow Prevention Assemblies Backflow Prevention Devices
Guidelines & Forms Backflow Prevention Tester List (PDF)
Frequently Asked Questions  


Need more information?

For more information about the Cross-connection and Backflow Prevention Program, please contact:

Email Daniel J. Peralez – Cross-connection Compliance Coordinator
or call (956) 983-6519

Email Kevin B Gamez
Senior Environmental Tech 
or call (956)983-6347

Email Jose A. Silva
Cross Connection Control Compliance Tech
or call (956) 983-6347

What is the Cross-connection and Backflow Prevention Program?

We all depend on having safe drinking water as close as our faucets, but a common plumbing problem, "backflow," can pose serious community health risks..

Today, the Texas Commission on Environmental Quality (TCEQ) and the city of Brownsville are requiring that any actual or potential cross-connections be protected from backflow. Brownsville Public Utilities Board's Cross-connection and Backflow Prevention Program enforces state and local backflow regulations.

What is backflow?

  • Backflow is the reverse flow of water or other substances into the treated drinking water distribution system. There are two types of backflow: back-pressure and back-siphonage.
  • Back-pressure happens when the pressure of the contaminant source exceeds the positive pressure in the water distribution main. An example would be when a drinking water supply main has a connection to a hot water boiler system that is not protected by an approved and functioning backflow preventer. If pressure in the boiler system increases to where it exceeds the pressure in the water distribution system, backflow from the boiler to the drinking water supply system may occur.  
  • Back-siphonage is caused by negative pressure (vacuum or partial vacuum) in the water distribution system. This situation is similar in effect to sipping water through a straw. In the drinking water distribution system, negative pressure (back-siphonage) occurs during a water main break or when a hydrant is used for firefighting.

What is a cross-connection?

A physical connection between drinkable water and a liquid or gas that could make the water unsafe to drink. Whenever there is a cross-connection, there is a potential threat to public health from the liquid or gas contaminants.

For example:

  • Garden hose: Backflow through cross-connections can by leaving a garden hose turned on and submerged in a container of water or other liquid. That material could siphon back into the drinkable water supply.
  • Private well: Backflow can also occur if an untreated water supply pump like a private well is connected to the drinkable water supply. The untreated water could accidently be pumped into the drinkable water of a home and the public water system.
  • Lawn sprinkler system: TCEQ regulations require that all lawn sprinkler systems be connected through a mechanical backflow prevention assembly - without one, the stagnant water from the sprinkler system could be drawn back into a home water system.

What is considered a health hazard?

Backflow may affect the quality of the drinking water in homes, businesses or facilities and has the potential to create health hazards if contaminated water enters the public water and is used for drinking, cooking or bathing.

Backflow events occur frequently although most do not create health hazards. Unprotected cross-connections with water supply plumbing or public drinking water piping systems are prohibited. Everyone is responsible for protecting the public water supply from backflow that may contaminate our drinking water. It includes complying with the plumbing code and avoiding unprotected cross-connections.

Who is responsible?

The official responsibility for preventing backflow occurrences is divided. State and local plumbing inspectors have authority over plumbing systems within buildings while state regulatory agencies and public water suppliers regulate protection of the distribution system at each service connection. Water customers have the ultimate responsibility for properly maintaining their plumbing systems. It is the water customer’s responsibility to ensure that unprotected cross-connections are not created and that any required backflow prevention devices are tested in accordance with state requirements and maintained in operable condition.

Preventing backflow situations in your home and business

  • Be aware of cross-connections, and take action to eliminate or isolate them
  • Do not submerge hoses or place them where they could become submerged in water or chemicals.
  • Use hose bib vacuum breakers on fixtures (hose connections in the basement, laundry room and on outside faucets/spigots).
  • Install approved backflow prevention devices on lawn irrigation systems and  fire sprinkler system services. Types of preventive required devices will be determined based on the potential type of pollutants or contaminants - high, low or moderate. In low hazard situations, the installation of a residential dual-check device might be allowed.

I live in an old building.

Unprotected cross-connections or improperly installed assemblies should be retrofitted to comply with the state law and local plumbing codes (30 TAC Chapter 290), regardless of the condition of the building.

On the supply side, federal law requires water suppliers or water companies, such as Brownsville Public Utilities Board, to protect their drinking water systems from contamination or pollution from backflow by cross-connections.


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