SIOUX FALLS, S.D. (KELO) — Along with the photogenic falls of the Big Sioux River, it is another iconic part of Sioux Falls.
It’s not a site, but rather a smell. A smell you can get a whiff of on some days in downtown Sioux Falls.
This infamous smell is well-known by longtime residents of Sioux Falls. The pungent odor is easily recognized and brushed off by many people who have ever lived the Midwest. Embraced by some in the community, the smell has also been commonly dubbed “the smell of money.”
But for people new to Sioux Falls and visitors, the smell can be one of the first questions asked when arriving to town.
So how come some days the smell can seem overpowering in parts of the city and many days it goes unnoticeable? Are there any regulations regarding nuisance smells? KELOLAND News went looking for answers about one of Sioux Falls’ unique secrets.
What causes the stench?
The Smithfield Foods plant, formerly known as John Morrell, has long been a part of Sioux Falls’ history, dating back to the early 1900s. As one of the largest pork processing plants in the nation, the plant deals with thousands of hogs each day. Naturally, when dealing with so many pigs, an overpowering stench can occasionally occur.
KELOLAND meteorologist Brian Karstens said the temperature in the atmosphere plays a key role in helping the smell linger on certain days. On days when the temperature is higher in the atmosphere than near the ground level, air particles containing the smell can’t dissipate as easily.
“It traps those smells closer to the ground level,” Karstens said. “That overhead warm air kind of traps that and that trapping effect can be really noticeable.”
After those conditions are met, Karstens said the wind direction determines where the air flow is distributed.
“In South Dakota, our wind becomes such a dominant factor that typically those things are fairly short-lived,” Karstens said. “With that industry you are going to have that. People who have grown up here, know that is going to be the case from time-to-time.”
No matter how bad it can smell, conditions can switch in the matter of minutes.
“You can always count on a change in our weather,” Karstens said.
Is the smell regulated or measured in any way?
A spokesman for the United States Department of Agriculture Food Safety and Inspection Service told KELOLAND News the federal agency only focuses on what is happening inside the facility. Anything like nuisance smell outside the building is not under federal jurisdiction and pointed to state agencies.
“Air quality and air pollution sources are regulated in South Dakota under the state and federal Clean Air Acts, however, DENR does not have statutory authority to regulate odor,” Brian Walsh with the South Dakota Department of Agriculture said.
Walsh said local government agencies and countries sometimes adopt ordinances for odor.
Craig Dewey with the Minnehaha County Commission Office said Minnehaha County does not monitor odor inside the city of Sioux Falls limits.
And the city of Sioux Falls does not monitor or regulate odor.
“Our department does not monitor or regulate odor. I also checked with Public Works and Health and while there are environmental issues we do monitor; odor is not one of them.” director of planning and development Jeff Eckhoff said.
KELOLAND News reached out to Smithfield Foods to ask about any steps the plant takes to mitigate the odor. We will update this story with any response we receive.