Roger Kelso
Columbus City Utilities is beginning a study of how many lead service lines are in its service area.
The Columbus Utility Service Board has approved a professional services agreement with Greeley and Hansen for “lead service line inventory development.” The contract amount is $58,300, said Columbus City Utilities Executive Director Roger Kelso.
He explained that Columbus, like many other cities, has locations where lead service lines still exist, so the department is working to create an inventory of these areas.
“So right now we’re going to be doing what I refer to as a ‘desktop study,’ ” said Kelso. “We’ll be going through all the written records, other types of records that we may have one way or another that give us an indication of what that service is. And then after we’ve quantified that, then we’ll start identifying, attaching projects to that to go through the removal process.”
He described this as a subject that the department will be focused on for several years.
When asked about the prevalence of lead service lines in Columbus, Kelso said the department’s “back of the envelope estimate” is that less than 10% of the city’s service lines contain lead.
He added that one of Columbus’ advantages is that all of its water comes from groundwater, which is relatively hard. This kind of water typically provides a “fairly decent level of protection against lead getting into the water” because it tends to scale pipes instead of corroding them like a softer water might.
“Because of that, the lead doesn’t get liberated from the pipe as it would in a surface water situation,” said Kelso. “So while we’ve got to do it, it’s not as if there’s an issue. When we do our testing and that sort of thing, it’s always well, well, well below any kind of limits in the water.”
Columbus City Utilities’ most recent quality report shows that, as of 2021, its drinking water was below the Environmental Protection Agency’s maximum contaminant level for lead.
“Every quarter, we test the metals at both water treatment plants as the water is exiting into our distribution system,” said quality assurance supervisor Angie Bowling. “And as you can see, that was zero for lead.”
Additionally, the department completes required compliance sampling for lead and copper every three years, as well as every time it introduces a new water source. This was the case for 2021, as the city had introduced two new wells.
This testing entails getting samples from 30 homes in the community that are identified as having either copper plumbing, galvanized plumbing or copper plumbing with lead solder.
“The water has to sit undisturbed … in the home, in their lines for a minimum of six hours,” said Bowling. “And the purpose of that is to see if their pipes are leaching or reacting with water sitting unused. Then they (the customer) collect the sample.”
The utility then picks up the sample for analysis. The EPA requires them to take the 30 samples and order them from the least to greatest lead content, then make note of the 90th percentile result (which would be the 27th sample).
For Columbus, the 90th percentile result was 3.59 parts per billion in 2021. Parts per billion (ppb) means micrograms per liter or one ounce in 7.35 million gallons of water, according to the quality report. The EPA’s action level for lead is 15 ppb; there were no samples over this level. Bowling added that most of the samples were “less than detect” for lead.
