A new filtration system is separating water from cow manure as part of a Dane County effort to clean up lakes and streams.
AQUA Innovations began operation earlier this summer of a $1.65 million system outside Middleton that takes liquid manure from three local dairy farms and extracts nutrients, such as nitrogen and phosphorus, and solids that can be spread onto fields as fertilizer.
Manure from the farms first goes to the neighboring GL Dairy Biogas project, which extracts methane from the manure and food waste to generate electricity. Dirty water is then piped into the AQUA system and in about two hours, treated water, considered clean enough to drink, trickles out of a 4-inch pipe into the Pheasant Branch Creek, which feeds into Lake Mendota.
The concentrated nutrients are returned to the farmers, who end up with less manure to haul and spread and can apply it more selectively, which reduces the risk of rain washing it off the land.
Too much phosphorus in the water causes plants and bacteria to flourish, which can lead to fish kills, smelly rafts of rotting weeds and blooms of toxic algae that force beaches to close.
County Executive Joe Parisi said the project is essential to the county’s ongoing efforts to clean up the Yahara watershed.
The system currently processes about 25 million gallons per year but can handle up to 40 million gallons. AQUA Innovations CEO John Sorenson said it costs about 0.4 to 0.5 cents per gallon to operate — a cost covered by the participating farms.
Sara Walling, agricultural resource management administrator for the state Department of Agriculture, Trade and Consumer Protection, called the project “a fabulous example of innovation” to help farmers.
While the Sharon-based company has built similar systems before, this is the first to serve multiple farms. Sorenson said he hopes to replicate the model elsewhere.
“We think it’s important that we be first and show others how it’s done,” Parisi said.
The Yahara Lakes: Giants Among Us
The Yahara lakes are the Madison-area's dominant natural feature. They affect our daily lives, yet we may not know them well. This Wisconsin State Journal series examines the history, impact and health of our lakes.
The Yahara lakes are a largely unknown world within our world. Running right through the middle of our lives, they affect us in ways so big and so familiar that that are easy to forget.
Tamara Thomsen is a marine archaeologist with the Wisconsin Historical Society and has documented hundreds of dives in the Yahara lakes. She a…
Madison's lakes have a long and storied history. Here's a look back at how they have changed over the years.
Wisconsin State Journal photographers capture the stunning beauty of the Yahara River chain.
Images from lakes Mendota, Monona, Waubesa, Kegonsa and Wingra, the jewels in the Yahara River chain of lakes.
Discover underwater oddities such as cars, boats, equipment and other objects beneath the surface of the Yahara lakes.
Lt. Gerald Stull's crash is also remembered.
One route travels above ground, the other below.
Lake levels have been rising.
You'll find cars, boats, ice shanties and much more at the bottom of the Yahara lakes.
Native peoples and European settlers have been drawn to the lakes.
It only recently was subject to academic study.
Many were destroyed by white settlers.
White settlers found the lakes attractive, just as did earlier inhabitants.
We asked Wisconsin State Journal readers for their stories and photos about the Yahara lakes. We received a tremendous response. It’s clear th…
“If Wisconsin is going to have swimmable, fishable, drinkable water in 30 years, we need better farm policies,” said one researcher. “What we’re doing is not working.”
Madison, Dane County, farmers and others are fighting back against phosphorous and invasive carp. Will their efforts be enough?
Lake levels are rising, and the area may be on the cusp of flooding unlike anything in the last 100 years, according to one expert.
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