cvg
Civil/Environmental
- Dec 16, 1999
- 6,868
Cleaner river = global warming?
That's the new argument from agency opposed to killing bacteria in city's sewage
Disinfecting wastewater discharged into the Chicago River would raise the Water Reclamation District's greenhouse gas emissions, officials say.
Chicago is the only major U.S. city that doesn't disinfect its sewage, and the agency that treats its wastewater has a new reason for opposing the idea:
It's bad for the environment.
Engineers with the Metropolitan Water Reclamation District of Greater Chicago recently completed an in-house study of its carbon footprint at the request of the elected board of commissioners. Going beyond the assignment, they also decided to look at how the footprint would change if it had to kill bacteria in sewage before pouring it into the Chicago River.
Starting to disinfect the wastewater — a change the 120-year-old agency has long opposed — would bolster the district's greenhouse gas emissions and thereby cause more bad than good, they concluded.
"With additional treatment, you have to weigh how much water quality is actually being accomplished with more harm to the environment in another way," said Louis Kollias, the director of the district's Monitoring and Research Department. "You're going to have to have it one way or the other. You can't have both."
Margaret Frisbie, executive director of the Friends of the Chicago River, called the district's argument an "ironic twist." Federal laws on clean water don't make exceptions for air pollution, she noted.
"We don't understand why they are so against disinfectant," she said. "This is not crazy, cutting-edge technology."
Whether to disinfect the sewage that enters the river, whose water is packed with bacteria, is a decades-old debate. The conversation has only intensified as more people participate in recreational activities like canoeing and kayaking on a resource that historically has served commercial purposes.
District officials already have argued that there's no evidence the public's health and safety are harmed by the water, that it is already clean enough and that disinfection will cost $500 million to install equipment plus ongoing expenses. The U.S. Environmental Protection Agency has estimated the cost at $242 million.
Catherine O'Connor, assistant director of monitoring and research for the district, said the engineers took it upon themselves to study the greenhouse-gas impact of three potential regulations — including disinfecting wastewater — because they consider them the most important ones on the horizon.
The analysis found that the district's 2008 electricity consumption produced greenhouse gases equivalent to 436,837 tons of carbon dioxide, a decrease from 520,419 tons in 2005, the last time it was measured.
The report also concluded that if the district had to disinfect wastewater, its carbon footprint would increase by 98,600 tons a year. Disinfecting sewage at the treatment plants would require more electricity, which means burning more fossil fuels. That would release more greenhouse gases into the atmosphere, where they contribute to global climate change by trapping heat.
That's the new argument from agency opposed to killing bacteria in city's sewage
Disinfecting wastewater discharged into the Chicago River would raise the Water Reclamation District's greenhouse gas emissions, officials say.
Chicago is the only major U.S. city that doesn't disinfect its sewage, and the agency that treats its wastewater has a new reason for opposing the idea:
It's bad for the environment.
Engineers with the Metropolitan Water Reclamation District of Greater Chicago recently completed an in-house study of its carbon footprint at the request of the elected board of commissioners. Going beyond the assignment, they also decided to look at how the footprint would change if it had to kill bacteria in sewage before pouring it into the Chicago River.
Starting to disinfect the wastewater — a change the 120-year-old agency has long opposed — would bolster the district's greenhouse gas emissions and thereby cause more bad than good, they concluded.
"With additional treatment, you have to weigh how much water quality is actually being accomplished with more harm to the environment in another way," said Louis Kollias, the director of the district's Monitoring and Research Department. "You're going to have to have it one way or the other. You can't have both."
Margaret Frisbie, executive director of the Friends of the Chicago River, called the district's argument an "ironic twist." Federal laws on clean water don't make exceptions for air pollution, she noted.
"We don't understand why they are so against disinfectant," she said. "This is not crazy, cutting-edge technology."
Whether to disinfect the sewage that enters the river, whose water is packed with bacteria, is a decades-old debate. The conversation has only intensified as more people participate in recreational activities like canoeing and kayaking on a resource that historically has served commercial purposes.
District officials already have argued that there's no evidence the public's health and safety are harmed by the water, that it is already clean enough and that disinfection will cost $500 million to install equipment plus ongoing expenses. The U.S. Environmental Protection Agency has estimated the cost at $242 million.
Catherine O'Connor, assistant director of monitoring and research for the district, said the engineers took it upon themselves to study the greenhouse-gas impact of three potential regulations — including disinfecting wastewater — because they consider them the most important ones on the horizon.
The analysis found that the district's 2008 electricity consumption produced greenhouse gases equivalent to 436,837 tons of carbon dioxide, a decrease from 520,419 tons in 2005, the last time it was measured.
The report also concluded that if the district had to disinfect wastewater, its carbon footprint would increase by 98,600 tons a year. Disinfecting sewage at the treatment plants would require more electricity, which means burning more fossil fuels. That would release more greenhouse gases into the atmosphere, where they contribute to global climate change by trapping heat.