Waukesha needs approval from the state’s Department of Natural Resources and all eight Great Lakes states’ governors before moving forward with its request.
City officials in Waukesha, Wisconsin spelled out why they need Great Lakes water to replace their radium-contaminated city water wells Thursday, and why tapping into the world’s largest freshwater supply makes more sense than drilling more wells.
But several more hurdles remain before the city can become the first outside the Great Lakes basin to tap into the lakes since adoption of a landmark protection agreement in 2008.
Under terms of the Great Lakes Compact, cities outside the basin must win approval of the governors from all eight Great Lakes states before diverting water from the lakes. Wisconsin’s Department of Natural Resources (DNR) also needs to sign off on Waukesha’s plan.
Waukesha Mayor Larry Nelson called the city’s efforts to secure a radium-free water supply “a critical public health issue,” the Milwaukee Journal Sentinel reported Thursday. For years, the city has been figuring how to replace city water from deep wells contaminated with naturally occurring radium and salt. The city needs to comply with federal radium-safe water standards by 2018 under a state order.
The city made its case for Lake Michigan water in a draft application released Thursday. The application notes that the city has already made great strides toward reducing its water use through conservation measures, but it maintains that conservation alone will not serve the city’s water needs.
Between 1988 and 2008, the city managed to decrease water use by 31 percent despite an 18-percent increase in population, according to the application. Recent efforts to encourage consumption, including a ban on daytime water sprinkling, water rates that promote conservation, a high-efficiency toilet rebate program, and public education, have resulted in an 11-percent decrease in use in the past three years.
Waukesha currently uses an average of 6.8 million gallons of water a day and will need an average of 10.9 million gallons a day when the city is fully developed, according to the Southeastern Wisconsin Regional Planning Commission (SEWRPC). The city and SEWRPC evaluated numerous water supply alternatives to meet those needs before settling on the three most feasible: using a mix of deep and shallow wells, switching to shallow wells alone, or switching to water pumped from Lake Michigan.
Besides the contamination issues with deep wells, the application notes that the deep water aquifer that those wells draw from is already depleted, and not reliable in the future. Switching from the deep wells to shallow wells exclusively would avoid the radium contamination but leave the city’s water supply vulnerable to other contamination sources, while reducing the volume of groundwater feeding wetlands, streams and lakes.
Given that, the city has concluded that using Lake Michigan for its water supply “has the least environmental impact and provides the greatest protection of public health.”
Any change to the city’s current water sources will be expensive.
Engineering and construction of pipelines to pump Lake Michigan water to the city and then return the treated wastewater to the lake via one of its tributaries, as required by the Great Lakes Compact, will cost about $164 million. Annual operating and maintenance costs for the pipelines are estimated at $6.2 million.
Switching to a series of shallow wells to supply the city would cost $174 million for construction, engineering, administrative, legal and other expenses, followed by an estimated $7.4 million a year to run and maintain the wells.
While the Great Lakes Compact prohibits water diversions outside of the lakes’ drainage basin, exceptions may be granted to communities in counties that fall at least partly within the basin such as Waukesha County.
The Wisconsin DNR will work with the city on a comprehensive environmental impact study for the project, the Journal Sentinel reported. The DNR will also invite the public to comment on issues that should be included in the study.
See previous Circle of Blue coverage: Waukesha’s Water Woes Herald Test of Great Lakes Compact