Council approves bonding for wastewater projectThe city of Superior is looking to eliminate nearly 11 tons of chlorine from its wastewater treatment process.
By: Shelley Nelson, Superior Telegram
The city of Superior is looking to eliminate nearly 11 tons of chlorine from its wastewater treatment process.
Tuesday night, the Superior City Council approved $3.6 million in bonding for the project that’s going to make it happen.
The project has been in planning stages for more than two years.
Currently, the city’s Wastewater Treatment Facility uses elemental chlorine to disinfect treated wastewater.
While chlorine is an effective method for disinfection, it also poses a risk to the public.
According to the Centers for Disease Control and Prevention, when liquid chlorine is released, it quickly turns into a poisonous, yellowish-green gas that settles near the ground and spreads rapidly; the extent of poisoning depends on how a person is exposed, the amount of exposure and the length of time the exposure exists.
Chlorine is detectable at 1 part per million, can cause vomiting and coughing at 30 ppm, lung damage at 60 ppm and death at 1,000 ppm, creating a risk for workers and citizens. It also releases chlorine into the Lake Superior watershed.
Instead, ultraviolet radiation would disable the bacteria in the treatment process so it would no longer be a threat.
Ultraviolet radiation works by altering bacteria at a genetic level, “deactivating them” so they can’t multiply.
The system works with phototubes and the water runs through them and is treated with ultraviolet radiation. Unlike chlorine, it doesn’t affect changes in organics living in the water.
In addition to the bonding, which came in with a 2.4 percent interest rate, funding for the project also comes from a Section 154 grant, a federal grant program created by U.S. Rep. Dave Obey, D-Wausau, to pay for infrastructure projects in the four northernmost counties of Wisconsin to protect the Lake Superior watershed.
Construction on the project could begin as early as March, said Steve Roberts, engineering manager with the Division of Environmental Services. He said it’s expected to be complete by November.