Chicago, although it does not disinfect its wastewater before releasing it back into the local waterways, has a pretty sophisticated water treatment system. The world’s largest wastewater treatment plant is located in suburban Stickney, and independent water quality assessments (such as those by the National Resource Defense Council) have rated the area’s drinking water as excellent within the past decade. (Ratings include test for contaminants such as lead and various carcinogens.) The quality of the water coming out of Chicago’s taps usually meets or exceeds the quality of the water people choose to purchase in stores, and it comes without the waste of plastic bottles.
Is, however, the area’s drinking water free of hazardous contaminants? Recently, an advocacy group hired an independent laboratory to test drinking water from 31 cities (including Chicago) for the cancer-causing metal hexavalent chromium. This is a metal that the US Environmental Protection Agency does not require municipal water suppliers to account for in water quality testing.
The amount in Lake Michigan water pumped to 7 million people in Chicago and its suburbs was 0.18 parts per billion, three times higher than a safety limit California officials proposed last year.
A handful of other cities were significantly above the proposed California limit, including Norman, Okla.; Honolulu; Riverside, Calif.; and Madison, Wis., according to a report to be released Monday. Levels in Milwaukee water were the same as in Chicago.
In other major cities, hexavalent chromium levels ranged from 0.20 parts per billion in Los Angeles and Atlanta to 0.18 in New York and 0.03 in Boston….
While the potential health threats of many pollutants are still being studied, researchers say there is a clear risk of stomach cancer from drinking water contaminated with hexavalent chromium, also known as chromium-6.
The news raises further questions. How was the proposed California limit established? What are the risks of drinking water with 0.18 parts per billion hexavalent chromium in both the short- and long-term? How might the water be remediated? (Bans on particular industrial activities in Lake Michigan? Advanced wastewater treatment techniques?) How do local, state, and federal regulators determine appropriate materials and levels to test, and how are these regulations implemented? We will likely learn more about these questions soon. Shortly after the report’s release, Illinois Senators Dick Durbin and Mark Kirk wrote a letter to EPA Administrator Lisa Jackson asking what the EPA might do about hexavalent chromium in the water, and the agency subsequently pledged to complete a review of the metal’s health risks by summer 2011. At the urging of the EPA, Chicago’s Department of Water Management will begin routine testing for hexavalent chromium.
The issue touches on points raised in several Roosevelt University seminars, including SUST 220 Water (offered by Professor Mike Bryson last semester) and SUST 240 Waste (offered online by Professor Carl Zimring this semester) about how we treat our waterways and the consequences of post-consumer and post-industrial waste dumping. If you are a currently-enrolled Roosevelt University student interested in taking one or more Sustainability Studies courses, please get in touch with your academic advisor. If you are not currently a Roosevelt University student, we encourage you to investigate our degree options, and our course listings. For more information, please visit our Sustainability Studies website, call 1-877-277-5978 (1-877-APPLY RU) or email applyRU@roosevelt.edu.