The City of Milwaukee’s drinking water gets high marks when it comes to “quality”.
The Environmental Protection Agency requires every public water supplier around the country to publish its annual report.
Thousands of Milwaukee water customers will soon find the report tucked in with monthly bills.
WUWM Environmental Reporter Susan Bence learned a bit more about what it takes to provide safe, drinkable water.
Unless you are a water quality expert, reading Milwaukee’s “consumer confidence report” could be a confusing muddle of microbiological and chemical data.
Carrie Lewis who heads the Milwaukee Water Works does not dispute the report’s complexity; the EPA requires that level of detail.
However, Lewis is quick to boast that Milwaukee exceeds the federal agency’s requirements when it comes to monitoring the Lake Michigan water it uses.
“The EPA actually starting a whole new containment monitoring requirement that ‘s going to go into effect soon, and they’ve got 30 chemicals on that list; and it just came out this week and we are already testing for 22 of those 30. And we test for them in the source water, the plant finished water and the distribution system. All that the EPA wants us to do is the distribution system,” Lewis says.
Technology has influenced the utility’s ability to get ahead of the requirement curve.
Lewis says, only 15 years ago, water testing meant filling a bottle, taking it to the lab and then repeating the process every few hours.
Today more than 150 instruments continuously monitor every inch of the water treatment process.
Water treatment protocol has also become more sophisticated.
“The biggest, biggest change here in Milwaukee was the change from chlorine as the major disinfectant to ozone as the major disinfectant,” Lewis says.
What prompted that change was a public health crisis – the 1993 outbreak of Cryptosporidium. It sickened hundreds of thousands, killed some people and forced residents to boil their water.
“Chlorine does not kill Cryptosporidium as we all learned the hard way but ozone does. And although ozone was put in as a disinfectant it is so powerful of these emerging contaminants that we’re coming to understand are out in the lake are just blown to smithereens by ozone when they come into the plant,” Lewis says.
Lake Michigan’s compromised ecosystem keeps Lewis’ water utility team on its toes.
Nonnative species not only plague the lake; if left unchecked, creatures such as the quagga mussel, could colonize and gum up the inside of the pipe carrying water from the lake into the drinking water treatment system.
Lewis says a tiny bit of chlorine takes care of that problem.