Fort Worth drinking water treatment violation is not public health concern, city says
Thanks to a loose cap on a piece of filtration equipment, Fort Worth’s water department has been cited by the Texas Commission on Environmental Quality for failing to meet minimum treatment requirements at its Westside Water Treatment Plant in March.
The city is required to notify all residents served by the Westside pressure planes, defined as isolated areas of the water delivery system that maintain water pressure. Official notices are being mailed to homes in parts of west Fort Worth and the suburbs of Aledo, White Settlement and Westover Hills, all of which purchase drinking water from Fort Worth.
The violation stems from an incident in which membrane filtration equipment stayed in service between March 1 and March 4 after failing a required “integrity test,” according to Fort Worth’s public notice. Those tests are conducted to ensure that there are no broken fibers in the filtration system that could reduce its effectiveness in removing harmful parasites and viruses commonly found in untreated water.
In addition to not addressing the integrity test failure, Westside operators allowed eight days to elapse before the equipment successfully passed the test again, one more day than is allowed by state requirements.
Mary Gugliuzza, the water department’s spokesperson, said there are no public health concerns associated with the violation, described by the state environmental agency as a “failure to maintain microbial treatment.” Fort Worth officials self-reported the incident to the commission, according to Gugliuzza.
Since opening nine years ago in Aledo, the Westside plant has not had any other violations, she said.
“Water Director Chris Harder lives in the Westside pressure planes area and has no concerns about the water he or his family drank during those three days,” Gugliuzza said in an email. “I want to emphasize this is not an ongoing problem. It has been resolved.”
So what led to the failed test at Westside? Of the five drinking water treatment plants in Fort Worth, Westside is the smallest and the newest. It’s also the only plant that uses membrane technology to remove parasites like Cryptosporidium and Giardia lamblia, which are often present in lakes and can cause intestinal illnesses if left untreated.
Westside uses the same processes as the four other plants in addition to membrane filtration, and final disinfection takes place before the water is sent to customers, according to the water department’s notice.
Membrane filtration takes thousands of fibers and places them into a tube known as a membrane module. The fibers act as barriers that selectively allow things to pass through based on pore size, according to the water department.
At Westside, modules are grouped together and placed into five racks, each consisting of more than 100 modules. On March 1, a Westside operator performed an integrity test on one of the racks and “acknowledged an alarm” resulting from the test, according to the water department notice. Not realizing the test had failed, the operator placed the rack back into service by mistake.
Three days later, Westside’s maintenance team found that air pressure was escaping from a loose cap on top of one of the 132 membrane modules on the rack, according to the public notice.
After the cap was tightened, the rack passed the integrity test, and no broken membrane fibers were discovered during inspections. Gugliuzza said the other 512 modules used for filtration reported no issues.
“The water quality coming off the invention granular media filters, which are before the membranes, was of exceptional quality,” Gugliuzza said by email. “And the bacterial testing done in the distribution system all passed.”
The city has released an interactive map showing which parts of Fort Worth and surrounding cities received water that went through the membrane filtration system. Residents can use the search function to find out if their home is among those affected by the violation.
