Dane County Executive Joe Parisi and members of the Clean Lakes Alliance met today in front of the county’s Natural Gas Plant at the Dane County Landfill, which helps ship renewable natural gas created from methane across the country. There, they proposed a new initiative to address manure runoff in Dane County’s lakes and streams.
As part of his proposed 2023 county capital budget, Parisi plans to begin a feasibility study to build a new, community manure processing facility.
The budget includes $3 million to pay for the year-long study, as well as purchase the land to build the new processing facility. Part of that study will include finding out how much manure can be processed, environmental and financial benefits, and where to put the facility.
The facility will be filled with cow manure, so the facility will smell. But Parisi says that, though the final location will be determined over the course of the study, it will be built in a rural area, and not in any neighborhoods.
Manure is used by farmers to fertilize the land, adding nutrients such as nitrogen, phosphorus, and potassium to the soil. Winter is often seen as an attractive time for farmers to spread manure: crops don’t grow during the winter and farmers tend to have more time on their hands, and the frozen ground is less likely to be compacted by tractors spreading the manure.
But Parisi says that winter manure spreading can cause a host of ecological problems, especially in Dane County.
“About 50% of the total phosphorus runoff into our lakes occurs between January and March, when winter spread manure is sitting on top of frozen soil and is vulnerable to spring rains, which is occurring more frequently due to climate change,” Parisi says.
The runoff from the cow manure can cause a crapload of issues for area lakes and streams. When the excess nitrogen and phosphorus make their way into the lakes, it helps proliferate blue green algae blooms, which can contain toxins that cause humans to feel sick, and can kill animals such as dogs.
Parisi says that, due to the number of dairy farms in the area, manure runoff causes a serious risk to the health of our lakes.
“There are close to 60,000 cows in the North Mendota Watershed that produce an amount of waste that is almost equivalent to around 2.5 million people. Unlike human waste, however, other than the farms currently utilizing digesters, cow manure is not treated, rather it is usually spread on fields, making it vulnerable to runoff,” Parisi says.
Currently, there are two manure digesters in Dane County that process manure from around 10,000 cows. The county’s goal with this new processing facility is to increase that to the manure of 40,000 cows, which would result in the treatment of 400 million gallons of cow manure every year.
Parisi says that this would not only greatly reduce the amount of runoff, but would also help the county become carbon neutral.
“A plant treating the manure of 30,000 cows would reduce the equivalent of 100,000 metric tons of carbon dioxide. This reduction is comparable to removing the emissions of nearly 255 miles driven by passenger vehicles, or 10 million gallons of gasoline each year,” Parisi says.
The processing facilities work by, basically, converting the liquid manure into a dry, solid manure. This dry manure still holds all the nutrients it needs to fertilize the soil, but becomes easier to spread accurately across the field. Meanwhile, the liquid manure removed can then be converted to methane gas, which then gets turned into natural gas, which is then sold through the county’s Renewable Natural Gas Plant next to the landfill.
James Tye is the founder and executive director of the Clean Lakes Alliance, a nonprofit dedicated to improving the water quality of Madison’s lakes and streams. He says that this new processing facility is a way to make both farmers and the lakes happy and sustainable.
“The (facility) is being built specifically for dairy farmers, so instead of them building their own facility, we are going to come together as a community and pay for it because of the importance of dairy in Dane County. It’s $1.4 billion in the economy, so we want to keep the dairy here, but we want to make sure that the lakes are healthy, and we protect the climate,” Tye says
If the study is approved in the county budget, and approved in later budgets once the study is complete, the new processing facility should open within the next few years.
Can’t wait that long and want to know when the best times to spread manure are now? The state department of Agriculture, Trade, and Consumer Protection runs a Manure Management Advisory System that gives daily updates to the current runoff risk of anywhere in Wisconsin.
Also included in Parisi’s 2023 budget, which is expected to be released next Monday, is an additional $2 million to begin the next phase of the county’s Suck the Muck initiative. The initiative, which removes sediment from area streams, has already removed 180,000 pounds of phosphorus and 56,000 tons of sludge from Dorn, Token, and Six-Mile Creek, all of which flow into Lake Mendota.
The next phase of the project, expected to begin in 2024, will focus on Door Creek near Lake Kegonsa.
Photo courtesy: Nate Wegehaupt / WORT News Team
