Do you know how we measure water quality?

Do you know how we measure water quality?
July 8, 2021

Louisville Water delivers high-quality water to our customers every day. Our drinking water, which we branded Louisville Pure Tap™, consistently wins awards for its great taste and high quality. But do you know how we do that?

Pure Tap comes from one of our two treatment plants. The Crescent Hill Water Treatment Plant is supplied by water directly from the Ohio River – most of the city’s drinking water comes from here. Our smaller plant, the B.E. Payne Water Treatment Plant, is supplied from groundwater that is naturally filtered through the aquifer.

During the water treatment process, most contaminants are removed via coagulation, sedimentation, disinfection and filtration (see chart). To make sure these steps are successful, we test turbidity, for chlorine, and for coliform during the treatment process and throughout the distribution system.

  • In the disinfection step, chlorine is added to the water kill any pathogens. To keep the water safe as it travels in our distribution system, ammonia is added to the water to provide additional disinfection and to stabilize the disinfectant in the distribution system. Our lab monitors the levels of ammonia and chlorine at the plants and in the distribution system and manages low levels by flushing lines and tanks, and by working with plant operations to be sure the correct ratios are being maintained at the treatment plants.
  • We measure the turbidity of the water, which is a measure of the clarity of the water. While turbidity itself has no health effects, particles that can cause turbidity can provide a vehicle for bacteria and other contaminants.
  • We also test for coliform bacteria, which can indicate the presence of disease-causing organisms.

Louisville Water measures these three metrics at nearly 300 locations throughout the distribution system each month. In addition, our lab conducts more than 200 daily monitoring tests at the water treatment plants and distribution system, which allows us to adjust the treatment system in real time to maintain high-quality water.

Discovering any issues in the distribution systems in real-time also provides us the opportunity to respond to and investigate issues that might trigger customer complaints, which we also track as a measure of whether we are providing high-quality water. Customer complaints usually relate to issues with discolored water, taste, and odor.

  • Discolored water can result from pipe disturbances of sediment containing metals, such as manganese and iron. These issues are normally managed by adequately flushing mains and lines where repairs have taken place.
  • Taste and odors can originate from compounds associated with algae or bacteria in the Ohio River or biofilms in water mains. Chemicals are fed at the treatment plants to address potential taste and odor issues. Maintaining adequate chlorine and ammonia ratios minimizes the potential for biofilms and other bacterial growth in the distribution system.

We release a water quality report every year to our customers that lists what we are testing for, what the levels are for each, and if we are meeting the requirements. And we meet the requirements year after year – here is the 2020 report, in case you missed it.