Whenever Mohammad Bayan stops at an out-of-town restaurant, he asks for water. Not bottled — just a glass of tap.
“I can tell right away what cities don’t apply ozone to their water,” said Bayan, senior engineer with Arlington Water Utilities, citing a key disinfectant of Arlington’s water treatment system. No ozone means water inferior to Arlington’s, he believes. “I’m very proud of it.”
To maintain that edge, the city is spending $14 million for new ozone generators and other equipment at both the John F. Kubala and Pierce-Burch Water Treatment Plants to maintain the quality and taste of city drinking water.
City officials say Arlington was the first in North Texas to begin treating all of its water with ozone, a gas that helps break down and remove organic impurities from water.
It became obvious we needed some work done.
Buzz Pishkur, Arlington water utilities director, referring to an outside study of the treatment plants’ needs
It follows that the utility is using some of the oldest ozone generators in the area. A city-commissioned study completed last year pinpointed the deficiencies, said Buzz Pishkur, director of water utilities.
“It became obvious we needed some work done,” he said. Replacing ozone generators, all of which were installed in the late 1990s, “was the highest priority of the projects to come out of it.”
The first phase, completed last spring, included replacing an aging ozone generator and part of the control system at the Pierce-Burch plant. On Feb. 9, the City Council approved $7.3 million for the second phase, which will replace the remaining ozone generators and control system components at both plants over the next 12 months.
Pierce-Burch and Kubala went on line in 1956 and in the late 1980s, respectively, Bayan said.
The $14 million cost of the entire project is funded with water utility bonds, which are paid back with revenue from water services.
Late next year the water utility will launch a five-year pilot study to determine if using a type of peroxide in part of the purification process would reduce the high electrical costs of generating ozone. Pishkur called use of peroxide “a theoretical enhancement to ozone,” saying the jury is still out on the science of it.
Ozone is applied in two steps of the treatment process, including when the raw water first enters Pierce-Burch from Lake Arlington, and Kubala from Richland Chambers and Cedar Creek lakes. Ozone initiates the breakdown of organic impurities in the water, which then flows into large sedimentation basins, where alum and other coagulants cause particles to clump together and fall to the bottom.
The water then is suffused with ozone gas a second time for disinfection, then run through a filter to remove whatever remains in the water, a “final polishing process,” Pishkur said. The last step is a chlorine inoculation just as the water heads out into the city’s 1,500 miles of water pipes, where it can knock out impurities between the treatment plant and the tap.
The last step is a chlorine inoculation just as the water heads out into the city’s 1,500 miles of water pipes, where it can knock out impurities between the treatment plant and the tap.
The upgrades won’t affect the capacity of water production — a total of 172.5 million gallons a day, which is well more than the city uses. In fact, just one of the plants could produce the average daily demand of 50 million gallons and even the peak demand of a typical summer, Pishkur said.
Pishkur’s and Bayan’s claims of making the best-tasting water around are not empty. The Texas Water Utility Association, an industry trade organization, and the state have bestowed their water-quality awards upon the city several times.
But since both officials have worked for the city for just four years, they don’t take any credit for the city’s pioneers of ozone purification.
“I think it’s fair to say that our predecessors put in a very dynamic and forethoughtful and very visionary process,” Pishkur said. “What we’re doing is making sure we maintain the system we have so that it can continue to be able to perform into the future. That’s why we’re doing this ozone project.”