Water Quality and Assurance Control

 In order to ensure Grapevine’s Public Water Supply System meets established parameters for Quality Assurance and Control, the Environmental Services Division provides technical support and sample collection. Routine samples are collected each month from various locations throughout the City’s system, including various private residences.   To view the Annual Water Quality Report, please CLICK HERE.


Backflow and Cross-Connection
Think of your Public Water System as a “closed loop” system intended to move one-way. Water is collected from a surface water source like Lake Grapevine. The “raw” water is then treated by a Water Production Plant to meet criteria for public supply. The treated “clean” water is then distributed throughout our City by a system of pumps, tanks and pipes. Once the treated clean water is used by the customer it becomes “wastewater.” Wastewater is collected by a different system of pipes and pumps and transported to a Wastewater Treatment Plant. Upon entering the Wastewater Treatment Plant, the wastewater is treated to meet established criteria. After it has been determined that the treated wastewater meets the criteria, it is discharged back to surface water. This completes the “Closed Loop” and the process starts over again. Backflow and Cross-Connection occurs when wastewater mixes with the clean water supply.

The term Backflow is used to describe the phenomena of water flowing backwards through the “Closed Loop” process described above. Backflow occurs as the result of a reversed pressure gradient, which could cause water in the Closed Loop system to flow backwards against the established one-way gradient. The term Cross-Connection is used to describe problems encountered if wastewater lines are connected to clean water lines and vice versa. Backflow and Cross-Connections are an environmental concern because the potential could exist for wastewater to mix with clean water.

The goal and objective for the City of Grapevine’s Backflow Prevention and Cross Connection Control Program is to protect the public water supply from contamination by an external foreign source. In order to accomplish this goal multiple City Departments are working together. The City of Grapevine Development Services Department inspects new installations on both commercial and residential facilities for potential sources of contamination. The City of Grapevine Public Works Department conducts inspections on existing systems and performs on-going monitoring.

The City of Grapevine Development Services Department maintains a list of Certified and Approved Licensed Testers as well as Inspection and Test Forms for Backflow and Cross-Connection testing. For more information call Development Services at (817) 410-3165 or stop by their office in City Hall at 200 South Main Street.


TO EXPAND YOUR KNOWLEDGE AND DISCOVER MORE ABOUT WATER QUALITY ASSURANCE AND CONTROL AS WELL AS OTHER ENVIRONMENTAL ISSUES VISIT OUR ECOLOGICAL ROUNDUP PAGE DOWN AT THE CONSERVATION CORRAL, CLICK HERE