Phosphorus reduction could pack financial punch
Sewer Plant closely watches potential change in state law
August 03, 2011 | 08:37 AMSharon Township — The amount of phosphorus leaving sewer treatment facilities may have to be dramatically reduced under a new proposal from the Wisconsin Department of Natural Resources.
If the proposal becomes law, it could also mean increases in sewer bills throughout the state.
Officials at the Fontana Walworth Water Pollution Control Commission — which treats wastewater for the villages of Walworth and Fontana and Kikkomann Foods, Inc — are carefully watching to see whether this proposal becomes law.
If it does, the plant may need to add an expensive step to the treatment process.
The DNR is proposing increasing the standards on the amount of phosphorus that leaves sewer treatment plants from one part per million to less than one-tenth of a part per million.
FWWPCC Plant Superintendent Dean Donner said the plant meets current standards by treating for phosphorus with chemicals.
"I don't think we can meet (one-tenth of a part per million) by using chemicals," Donner said.
If the proposal becomes law, Donner said the plant would need to add an another treatment phase to the facility. "We could be talking about $1 million," he said.
To reach the proposed standard, Donner said the plant would likely have to construct another building, possibly a sand filter. Donner said this building must be enclosed to protect it from the weather.
"It will be another unfunded mandate from the state," Donner said.
FWWPCC isn't the only sewer treatment plant in the state that could see a major price tag come with a standard change.
Officials at the Madison Metropolitian Sewerage District estimate the upgrade could cost $85 million and at the Milwaukee Metropolitan Sewerage District is could be as much as $500 million, according to an article in the Wisconsin State Journal.
Wastewater that is treated at the Sharon sewer treatment plant eventually is discharged into the Piscasaw Creek.
However, the wastewater treatment plant isn't the only source of phosphorus for the creek.
"The funny thing about the Piscasaw Creek is that a lot of phosphorus comes from farm lands," Donner said.
South of the treatment plant, for miles, the Piscasaw Creek runs adjacent to agriculture land, which often discharges phosphorus — a common ingredient in fertilizer — into the water.
"We will follow the rules, but what would we be accomplishing?" Donner asked.
Donner said phosphorus comes to the sewer treatment plant through chemical manufacturing and household products. Soaps and other cleaning products often contain the chemical, he said.
Phosphorus free versions of soaps and cleaning products are often available, but they typically carry a higher price tag, Donner said.
The treatment plant recently completed a $5.2 million expansion, which received 50 percent of its funding from federal stimulus dollars.
That expansion included an additional oxidation ditch where solids are broken down, an ultraviolet disinfection tank, which further breaks down materials, and a new mechanical bar screen.
The plant also added a new storage building, expanded its administrative building and modifications were made to an existing influent pumping station.
The plant's lab also received an expansion and new equipment.