The decline of the deep aquifer
For more than a century, the system of wells that served Waukesha and surrounding communities provided safe and abundant drinking water to area citizens.
Over time, though, it was discovered that the thick layer of shale that sits above the deep aquifer in this region was hampering recharge. And as water levels decreased, concentrations of naturally occurring contaminants such as radium have increased.
When Waukesha transitions to using Lake Michigan as its water supply, levels in the deep aquifer are expected to begin rising again.
Is it Radium or Radon?
Federal EPA guidelines issued in 2000 set new standards that lowered the amount of allowable radium in drinking water. Radium is a naturally occurring solid that is found in the earth’s crust, and is known to be harmful to people when ingested in significant amounts.
Radon, on the other hand, is a gas that radium emits as it decays. Because it can enter the body more easily, radon is considered more dangerous than radium. Neither is good, but it is radium that has undermined the deep aquifer as water levels have fallen.
To be clear, Waukesha’s current drinking water is safe, and the Utility uses available technologies to reduce radium levels. However, such treatment is only a short term fix, as it does not address the underlying issue of long-term depletion.
Getting it right the first time
Waukesha could have limped along in compliance with the EPA’s radium standards by adding more removal systems and sinking more shallow groundwater wells. Such a quick-fix definitely would have been a lot less time-consuming, but more expensive in the long run.
It also would have been environmentally irresponsible: thousands of acres of existing wetlands would have been jeopardized, and stresses on the deep aquifer would continue unabated.
By going through the long and difficult process of transitioning the city’s water supply to Lake Michigan, Waukesha is doing the right thing for the health of its citizens — and the health of the watershed — for the long term.