Lead level in Glencoe water below required amount
Tom Weathers, superintendent of the Glencoe Water Plant, checks on the sodium hydroxide machine at the water plant July 19. | Curtis Lehmkuhl~Sun-Times Media
Updated: September 3, 2012 12:59PM
GLENCOE — New tests show Glencoe water’s lead content is far below the level required by the Illinois Environmental Protection Agency.
Glencoe tests have, in the past, exceeded that level slightly, but it’s not the fault of Lake Michigan’s water. Or even, really, the folks at the water plant.
The lake’s water is virtually lead-free. And there’s no more lead coming out of the Glencoe Water Plant than goes in.
But there are about 700 buildings in town, mostly houses, with old service lines carrying water inside from the water mains. And those old pipes have lead in them.
Under environmental regulations, independent labs must test the water coming out of 20 faucets of such lead-pipe-fed houses like those in Glencoe every three years. If 10 percent come out with over 15 parts per billion, the town flunks. Residents are informed, and twice as many houses have to be tested twice a year until less than 10 percent come out under 15. Then, it’s back to every three years.
In 2008, tests of two Glencoe houses came in over 15 ppm. That’s 10 percent. In 2010, Glencoe passed, but just barely.
But this year, flying colors. An average of 3.7 parts per billion, and nothing higher than 7.8.
How’d they do it? Not by cleaning the lead out of the water, because lead doesn’t even get in the water until the parkway.
The way you do it, Glencoe Water Plant Supervisor Tom Weathers said, is by adding some innocuous chemicals to the water that will combine with the lead and copper in the water and form a scale on the inside of the pipes, “like arteriosclerosis,” he said. In a good way.
Water-borne lead tends to become part of the scale, and the scale shields the water from lead in the pipes.
For years, the main chemical used around here to bar lead — and copper — was blended polyphosphate. Weathers thinks it doesn’t work well, and decided to change to orthophosphate.
He also wanted to encourage the chemical reaction a little by making the water just a touch more basic, by adding sodium hydroxide, also known as caustic soda or lye.
Caustic soda is used in water treatment from Arkansas to Australia — but not in the Chicago area. Around here, water plant operators tend to want to let Lake Michigan’s naturally soft water alone, Weathers said.
Caustic soda sounds — well, caustic — but it’s not a problem when you’re bathing the baby, Weathers said.
“Coca-Cola has about 1,000 parts per million,” Weathers said. “We’re at about 1 part per million.”
Glencoe won the water industry’s contest for Illinois’ best-tasting water in 2011, but was a bridesmaid this year when Park Forest took the title.
“We think our water still tastes very good. No difference,” Weathers said.
“It’s hard to (repeat) on the local level. All Lake Michigan water tastes good.”
The Glencoe changes cost about $10,000, and a lot of paperwork with regulating agencies, Weathers said.
Don’t want to take chances? If you live in a house with lead pipes, run your water for a few seconds before filling a glass, if the faucet has been unused for over six hours. Or look into replacing the service lines. It costs around $5,000 for many houses.
Don’t know if your house has lead service pipes? Call Village Hall. They have a list.