PWS Total Coliform Rule Guidance
Public Water Systems (PWS) serve an important function of our modern society. As the name implies, they are entities that supply water that is safe for public use. A PWS might be a city, a neighborhood, a restaurant, a hotel, a gas station, or a man-camp meeting place that has met certain criteria. Under the guidance of the Environmental Protection Agency (EPA), rules are set in place as to how water can be safely provided for public use. In Texas, the authority to make these rules is delegated to the state, which is administered by the Texas Commission on Environmental Quality (TCEQ). These rules are quite extensive and require systems to design, build, and operate under specific criteria.
One of these rules is the Total Coliform Rule. Coliform is essentially a group of rod-shaped bacteria with particular characteristics. Within this group is a common gastrointestinal pathogen called Escheria Coli, or as more commonly recognized, "E. Coli". In the world of water quality, E. Coli is known as an indicator organism, one that may signal the presence of other (potentially harmful) pathogens. It is most efficient to test a water source for contamination by looking to see if this indicator organism is present.
In 2013, the EPA published the Revised Total Coliform Rule (RTCR) in the Federal Registry (followed by minor corrections in 2014). The rule is a revision to the 1989 Total Coliform Rule. The RTCT became effective to all PWSs on April 1, 2016, except those subject to the Aircraft Drinking Water Rule.
TCEQ adopted the rule (effective 2016) and released guidance in June 2021 in the form of document RG-421. The guidance aims to help the regulated community understand and keep their PWS in compliance by giving specific criteria for sampling, testing, and logging water samples. Should a test be positive, RG-421 lays out what procedures the PWS owner/operator should follow. Something to keep in mind, RG-421 is an excellent "guide", but should it deviate from the rule, the RULE will take precedence. The guide is a great resource for learning the procedures and the terminology that are often utilized by TCEQ staff and inspectors.
In summary, if you are a PWS under the jurisdiction of TCEQ (and EPA), the RG-421 guidance will help you to understand what actions you must take to remain in compliance. As of the date of this writing, the RG-421 guidance may be found at the following link: https://www.tceq.texas.gov/assets/public/comm_exec/pubs/rg/rg-421.pdf
Westward is ready to assist you with any of your PWS needs, including helping to ensure compliance with the Total Coliform Rule and understanding the new guidance document. Please reach out to us if you have any questions regarding your current or prospective public water system project.