GREEN BAY — Brown County, home to Wisconsin's third-largest city, may seem an unlikely testing ground for the future of dairy farming.
The lower Fox River runs through the middle of the county — a watershed with some of the most intensive manufacturing in the state.
But there is plenty of agriculture, too, including a heavy concentration of large-scale cattle operations that are changing the face of dairying as hard times push many smaller farmers out of business.
Starting near Lake Winnebago, the watershed is a veritable sink of runoff from cities and farms that empties into the ecologically fragile waters of the Fox and, in turn, Lake Michigan's Green Bay.
It needs to be fixed. Regulators want less dirt and grime, manure, fertilizer and everything else that runs off the land, to keep it all from polluting the bay.
The projected cost of repairing the damage is hundreds of millions of dollars over the decades to come — for a single watershed, one of many that fail to meet Wisconsin's water quality standards.
“The public has got to understand that you can foul up a system for a 100 years — you are not going to turn back the clock, ever; and you are not going to turn it back fast,” said Val Klump, dean of the School of Freshwater Sciences at the University of Wisconsin-Milwaukee.
The school uses its research vessel, the Neeskay, to bring students and faculty to Green Bay to study conditions, including the bay’s “dead zones,” where summer oxygen levels in some areas plunge to nearly zero.
The bay's low oxygen season — measured from the first day of low readings to the last, but where higher levels can be reported in between — has ranged from 12 days to more than three months over the past three decades.
Agriculture accounts for nearly half of a key pollutant — phosphorus — that is entering the river basin, according to the state Department of Natural Resources.
It comes in the form of soil, commercial fertilizer and liquefied manure that send stalks of corn and other crops soaring but wreaks havoc when there's too much and it washes into waterways.
Even though Green Bay contains less than 2% of the total water volume of Lake Michigan, it represents one-third of the entire nutrient runoff that flows into the lake, a situation that revs up algae blooms and damages the bay’s ecology.
Brown County ranked fifth in Wisconsin in cattle and calves with 125,000 head in 2018, according to U.S. Department of Agriculture figures.
The county’s 20 megafarms — known as concentrated animal feeding operations, or CAFOs — tallies second highest in the state, according to the DNR. The average CAFO in the county has 1,617 milk cows, 598 heifers and 648 calves.
The average size of a Wisconsin dairy farm is about 150 cows.
And yet Brown County has the smallest land base among the biggest livestock counties.
“I do think that it is a major concern for the system,” said Kevin Fermanich of UW-Green Bay, who studies the effects of land practices on the bay.
“Do we have enough land that is appropriate for … applying the manure being created by all of these dairy cows?”
After Progress, Some Setbacks
The federal Clean Water Act of 1972 required factories and wastewater treatment plants, known as “point" sources, to install equipment to limit what they dumped in the water. Businesses and city sewage utilities are regulated under a state permit.
“Industry put in billions of dollars — paper mills, cheese factories,” said George Meyer, executive director of the Wisconsin Wildlife Federation and a former DNR secretary.
“The state spent $3 billion … there was cost-sharing to municipalities to put in treatment plants.”
But protecting waters from so-called nonpoint pollution is a bigger challenge.
Cities are required to control stormwater; CAFOs must follow plans on how and where they spread manure; and in some cases, state and county requirements limit manure spreading on smaller farms.
But there is simply less regulation over what runs off the land.
“I can remember at the time saying, in about 20 years or so, we'll have this taken care of,” said Meyer, who led the DNR's enforcement division for 10 years and served as secretary from 1993 to 2001 under Republican administrations.
“It will take longer because we are dealing with urban runoff and farm runoff, and there’s more sources and it’s more complicated.”
But despite improvements under the Clean Water Act, the number of lakes, rivers and streams that fail to meet water quality standards has been on the rise.
Complications From Climate Change
A changing climate is also complicating the problem.
Climate models for Wisconsin and the Upper Midwest have found that warmer temperatures help keep higher volumes of moisture in the atmosphere, leading to increased frequency and intensity of rainfall and snow, which can wash pollutants into waterways.
UW-Green Bay's Fermanich said the last two years of wetter-than-normal conditions are worsening soil runoff in northeastern Wisconsin.
Precipitation in the City of Green Bay this year is more than 18 inches above normal at nearly 47 inches, according to the National Weather Service.
“I think that we have lost some progress in the last two years,” Fermanich said.
A Nutrient Diet for the Basin
Like other heavily used waters in the state, the lower Fox and the southern end of Green Bay fail to meet state standards for phosphorus and another pollutant, total suspended solids.
The DNR has developed a plan to cut levels of algae-causing phosphorus by 60% over the next 20 years, essentially putting the basin on a nutrient diet by trying to limit what gets in the water.
One aim is to improve levels of dissolved oxygen.
Influenced by factors such as wind, rainfall and water currents, Green Bay’s levels of oxygen available to aquatic life fluctuate from year to year. But the trend is unmistakable.
The number of dead zone days is increasing, according to data compiled by UWM’s School of Freshwater Sciences.
In 2018, researchers counted 22 days when conditions qualified as a dead zone at a key monitoring station in the southern end of the bay. Since 1987, that ranks as 4th highest for readings of dissolved oxygen below 2 milligrams per liter.
Number of Days With 'Dead Zone' Oxygen Levels
Dead zones are created when plants and algae, fed by nutrients, die and sink to the bottom. As they decompose, the dissolved oxygen in the water is consumed.
"We can solve the problem," UWM’s Klump said. “But it’s a complex one. And it involves what’s going on in the watershed.”
A coalition of groups in the Green Bay area estimates the cost of reducing the share of phosphorus from farms that washes into the basin at $280 million to $340 million over the next 20 years.
For context, the cost of the 2003 renovations at Lambeau Field was $295 million.
But who will pay isn’t entirely clear. Farmers are expected to cover some of the costs. So will taxpayers.
“In the Green Bay system, I am more encouraged than I have ever been,” Klump said. “I think the ag community really understands the nature of the problem.”
The cost estimates for the cleanup are based on a five-year pilot project of the Green Bay Metropolitan Sewerage District on 15-mile Silver Creek, which flows through another creek to Green Bay.
During the program, agronomists and farmers experimented with an array of strategies:
Planting cover crops to prevent erosion, constructing wetlands to retain water, creating strips of grass along waterways to intercept pollutants and plowing fields in ways where there is less soil disturbance.
The result: Less phosphorus is turning up in Silver Creek.
Green Bay’s sewerage district, also known as NEW Water, needs a state permit to dump its treated waste into the bay and faces a DNR requirement to reduce its phosphorus load by more than 9,000 pounds a year.
It could cost $100 million for the district to upgrade treatment systems to reach that level.
So officials are exploring a different approach, one that would instead have NEW Water — and its customers — pay to help farmers implement better phosphorus-reducing practices.
As it stands, if farmers agree to adopt practices to manage runoff from fields, they can participate in a state program that picks up 70% of the cost.
The DNR says requests for cost-sharing from farmers typically exceed the amount of state funding available. But requests have dropped over the past two years amid dairy’s downturn.
Jeff Smudde, NEW Water’s director of environmental programs, said that it would cost an estimated $38 million over 20 years to help underwrite better farming practices in two key Fox River tributaries — Ashwaubenon and Dutchman creeks.
That's far less than the $100 million for treatment plant upgrades.
And it would keep roughly double the amount of phosphorus out of the waterways, nearly 19,000 pounds in all.
Smudde calls the accumulated efforts of farmers the "snowball effect."
"We can achieve more by working in the watershed," he said.
Andrew Mollica of the Milwaukee Journal Sentinel staff contributed to this report.