Cross-Connection Control Program

General Information

A cross connection is a point in the public water supply or in the customer’s water system that is connected directly, or has the potential of being connected, to a source of non-potable substance through which contaminants or pollutants may enter the public water supply or the customer’s water system. Please review our Cross-Connection Program brochure for more detailed information concerning the purpose of a cross-connection control program.

The installation of "non-return devices" such as backflow prevention assemblies, check valves, dual check valves, pressure reducing or regulating valves, and in some instances water softeners between the water service connection and the premises domestic water heater may create a "closed domestic water system." It is the responsibility of the customer to control thermal expansion created by the installation of any device that prevents relief through the building supply. Please see the attached brochure for more information.

Effective January 1, 1996, the Texas Natural Resources Conservation Commission (TNRCC) has required public water suppliers such as, El Paso Water Utilities (EPWU), to enforce new rules and regulations in order to contain hazards at the service connection, and protect the public water supply from potential contamination or pollution due to cross connections. The method used to contain hazards at the service connection is by the installation of a backflow preventer device. The Public Water Supplier is responsible for providing safe drinking water to the customer. However, the customer is responsible for the safety of the water within their premises and preventing any pollution hazards from backflowing into their water system or the public water supply. There are therefore two types of cross-connection control that are implemented and enforced by City of El Paso:

  1. Isolation Cross-Connection Control - provides protection to the occupants within the customer’s premises by the installation of approved backflow prevention assemblies at each cross connection within the customer’s water system. The City of El Paso’s Department of Public Inspection is responsible for inspection and enforcement of isolation cross-connection control requirements.


  2. Containment Cross Connection Control - provides protection of the public water supply from the backflow of contaminants or pollutants from the customer’s premises to the city’s water mains by the use of an air gap or an approved backflow prevention assembly at each water service connection to a customer’s water system. EPWU is responsible for monitoring and enforcing containment cross connections. Containment cross-connection control does not provide protection to the occupants of the premises, but is considered as additional backflow protection and does not negate the use of backflow prevention on internal hazards by isolation control as outlined and enforced by the Department of Public Inspection.

Backflow Prevention Assembly Inspection and Testing

All containment backflow prevention assemblies within the jurisdiction of EPWU must be tested for proper operation by private sector certified backflow prevention technicians at the time of installation, repair, or relocation and at least on an annual schedule thereafter or more often when required by the Cross-Connection Control Program Manager. In addition, containment backflow prevention assemblies installed on new services must be tested by certified backflow prevention technicians for proper operation immediately upon installation and before water service is turned to the premises.

TCEQ maintains an approved list of State Certified Backflow Prevention Assembly Test Technicians for the customer to contact for testing of your backflow prevention assembly. Click here to obtain instructions for looking up test technicians on TCEQ's website.

EPWU Cross-Connection Control Regulations and Manual of Procedures

EPWU’s Cross-Connection Control requirements can be found in EPWU’s Rules and Regulations No. 1, Section V – Protection of Water Supply. EPWU’s Rules and Regulations can be found on this website under the “Customer Service” menu item. More details concerning cross-connection control requirements are available in EPWU’s Cross-Connection Control Manual of Procedures (Click on the underlined link to download this manual).

Approval of Backflow Prevention Assemblies

All backflow prevention assemblies that are installed for containment cross-connection control must be approved by University of Southern California Foundation for Cross-Connection Control and Hydraulic Research. The manual or literature that came with a backflow prevention assembly should indicate that it has been tested and approved by this foundation. For any questions concerning approval of a specific backflow prevention assembly, or any other questions concerning testing requirements, please contact EPWU’s Cross-Connection Control Program Manager 915-594-5777.

Contact Information

For additional information concerning El Paso Water Utilities’ Cross-Connection Control Program, please email the Cross-Connection Control Manager or call 594-5777. You may also contact the Cross-Connection Control Program Secretary at 594-5440.

 Certified Backflow Test Technician Section