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A new report authored by the Alliance for the Great Lakes in collaboration with several leading environmental groups warns that Chicago must join other major U.S. cities and disinfect its wastewater, or else the city will continue threatening public health by releasing bacteria and other disease-carrying agents into the Chicago River.
"Protecting Public Health, Caring for Chicago’s Waters: An Agenda for Action," notes that Chicago’s sewage treatment district is one of just a handful among the nation’s major cities, and the only one in the Great Lakes region, that doesn’t disinfect wastewater, a final treatment step that kills viruses, bacteria and pathogens that threaten public health.
"We need a new vision, one that treats water as vital for recreation and life itself," said Dale Bryson, chairman of the Alliance for the Great Lakes. "Getting MWRD to disinfect its waste is the first step toward moving ahead with the new vision for Chicago’s waterways."
The report states that MWRD could catch up with other cities for as little as $8.52 per person per year, by employing a technology that disinfects wastewater using ultraviolet light. Other available strategies include ozone and chlorination/de-chlorination treatments.
The Sierra Club, Natural Resources Defense Council, Friends of the Chicago River, Prairie Rivers Network, and the Environmental Law & Policy Center collaborated with the Alliance on the report, which follows another recent Alliance report on the Chicago River system. That study found a rise in paddling, fishing, birding and other forms of public recreation along the Chicago River, all activities that would be protected by river improvements and the investment dollars they bring to local economies.
More than 100 years ago the Chicago River was reversed to flow away from Lake Michigan and protect public drinking water supplies. During heavy rainstorms, however, MWRD is forced to occasionally reverse the river’s flow – prompting swimming bans and beach closings along the Lake Michigan shoreline. Protecting Lake Michigan’s health is vital not only for recreational users, but because it is a source of drinking water for 10 million people, and is part of the larger Great Lakes system that provides drinking water to as many as 40 million.
The report found that Memphis, Tenn., St. Louis, and Kansas City, Mo., are the only major U.S. city treatment districts, other than Chicago, that do not disinfect their wastewater. However, those cities are expected to disinfect in the near future.
A full copy of the report and accompanying fact sheet is available online at http://www.greatlakes.org/news/pdf/disinfection.pdf.