Eww, that smell: Maryland legislators consider solutions to farm sludge odors

To Kathi Green, the odor wafting through her Carroll County community each growing season smells like rotting flesh.

“If you’ve ever smelled a dead animal that’s sat around for a day or two?” Green said. “It’s overbearing. It just takes your breath away.”

Over the past two years, the stench has started in March, when farmers across the state are allowed to begin spreading fertilizer on their fields after a winter hiatus.

But the smell isn’t coming from manure. Green and her husband believe the material being spread on the field close to their home in rural Mayberry is a waste product from processing food — most often chickens — called DAF.

For the poultry industry, spreading the waste on farms is a popular and cost-effective solution, as the material contains many of the nutrients that help plants grow. But it also comes with an incredible stench. And if it’s applied too frequently, or stored in open-air pits, that smell can wreak havoc, often making time people spend outdoors unbearable.

Residents like the Greens have called on local officials and the Maryland Department of Agriculture to do something about it. So far, not much has changed.

But they’re hoping that a bill in Maryland’s General Assembly this year could help.

The bill would give the state new tools to address problematic DAF usage, including the ability to inspect farms during spreading without the owner’s permission. It would add a permitting system focused on food processing residuals, allowing the state to set more guardrails on land application and storage. It would increase fines for bad behavior, such as excessive spreading.

In Mayberry, which is northwest of Westminster, neighbors say the smell is a near-continuous presence from springtime through mid-December — when spreading is cut off for the year. Some residents say they’re forced to stay indoors with their windows closed.

Activities like mowing the lawn, waiting for the school bus or washing the car have become a headache, longtime Mayberry resident Randy Cole said.

“There’s no more stopping and talking for half an hour, 40 minutes, at the top of the driveway,” Cole said. “We’d always talk. Talk about politics. Talk about the weather, I don’t know. But we’d always talk. But that’s all gone now.”

The Baltimore Sun’s efforts to reach one farmer who neighbors say spreads the sludge were unsuccessful.

Over the past two years, the Greens and their neighbors have tried unsuccessfully to compel the farm owners to slow the spreading — on their fields in Mayberry, and another set of fields in northern Carroll County — and follow best practices for odor control during storage and application. They’ve built a network of residents who track the malodorous spreading — and the heavy traffic along winding country roads from trucks that deliver the sludge.

Some state legislators hope the pending bill, which has bipartisan support, could correct an imbalance between Maryland and other states.

A September 2023 study by University of Maryland agricultural researchers found that Maryland is the largest importer of the smelly sludge in the Delmarva region, receiving substantial shipments from Delaware and Virginia. State regulations appear to play a role, the study found. In Virginia, unlike in Maryland, applying DAF to a farm field requires a special permit.

“We are becoming a dumping ground for this material,” said Del. Sara Love, a Montgomery County Democrat who sponsored the bill alongside several Carroll County and Frederick County Republicans.

DAF is actually the name of an industrial process, called dissolved air flotation, that treats waste left over from plucking and cutting chicken for sale. With solids like feathers and bones removed, the liquid is treated in large tanks, so that fats, oils and grease rise to the surface. They’re skimmed from the top, and become the DAF material, which agricultural researcher Stephanie Lansing likens to a “brown milkshake.”

The material’s use on farm fields isn’t new, said Lansing, a professor in the University of Maryland’s College of Agriculture and Natural Resources, and lead author of the 2023 study. But as Maryland and other states increase the regulation of how many nutrients can be applied to farm fields, that could limit the areas where DAF can be applied, and bring it to new farm fields.

“As we’ve started to — and other states have started to — increase their regulations around nutrients, this material is moving farther and farther away from their point of origin,” Lansing said. “You’re seeing it being places you didn’t used to see it. You’re seeing more of these storage systems being built.”

Odor and spill complaints also have arisen on Maryland’s Eastern Shore, which receives the bulk of the DAF material flowing into the state. As a result, Caroline County recently issued a temporary ban on new DAF storage areas on county lands.

Matt Pluta, the Choptank riverkeeper from ShoreRivers, said he’s dealt with DAF complaints for much of the past decade. He believes part of the problem is that DAF can be cost-effective — and even lucrative — for farmers, compared with buying commercial fertilizer.

“Haulers are getting paid to take this, and then are charged with finding the cheapest way to put it to work. And that, I think, is where a lot of the problems are coming from,” Pluta said.

The bill remains in committee in the General Assembly, with a March 18 deadline to remain viable by passing either the House or the Senate. But it has attracted a wide base of support, including from the Maryland secretary of agriculture, environmental groups and residents.

The Delmarva Chicken Association, which represents the poultry industry, also supports the bill — with some suggested amendments. It said the legislation would allow officials to address “the few bad actors” among about 70 farms using DAF in Maryland.

Currently, farmers are required to submit “nutrient management plans” to the state agriculture department each growing season. While such plans set limits on the quantity of nutrients that can be applied to a field, they don’t dictate what materials they come from, said Hans Schmidt, the department’s assistant secretary of resource conservation.

“There’s a lot of water in these [DAF] materials, so it gives the ability for the farmer to apply multiple times,” Schmidt said. “Where the problem is, is that the more often you’re out there, the more often you’re applying to meet what the nutrient management plan is, the odor doesn’t go away. It perpetuates.”

With a permit system, state officials could set spreading limits for DAF, Schmidt said. And with new inspection powers, the limits would be easier to enforce, he said.

Environmental groups backing the bill, including the Chesapeake Bay Foundation and ShoreRivers, hope it will curtail excessive spreading. The nutrients contained in DAF — and other types of fertilizer — are among the chief pollutants damaging the Chesapeake. When they run off the land, these nutrients enter waterways, causing damaging algae blooms.

There are plenty of ways DAF can be stored and applied responsibly, Lansing said.

Composting and anaerobic digestion are both good solutions, she said, because the material is processed in closed containers. And when the material is applied, it can be injected, or tilled into, the soil to reduce odor. In 2022, Maryland began requiring farmers to use at least one of those odor control steps, Lansing said.

Impacted residents in Carroll County hope the new Maryland legislation will help. But it may not address all of their concerns: Some want limits on the number of applications allowed per year, and the duration of storage.

Cole, 71, said it was particularly upsetting that the odor began in the community shortly after he retired, when he was eager to spend more time at home after years of a lengthy commute to Washington, D.C.

“My biggest problem right now is finally being able to retire, and being able to enjoy what I worked for my entire life,” Cole said. “But the rug is being pulled out from under us.”