It's embarrassing! You have out of town guests and you're showing them around all the awesome sites and then you hear, "What's that smell?" You never really have a concrete answer, it could be the rendering plant, it could be pigs in the distance, it's never consistent, but it usually rears its smelly head on a hot Summer night!
The City of Des Moines has had an odor control line for awhile. If they receive ten or more complaints from a specific odor, then they investigate. Due to that protocol, they have been able to pinpoint three specific causes of odor in the city. But has that solved the problem? Clearly, no.
They have money invested in a study and discussed at a recent city council meeting holding businesses causing the odor pollution to come up with a plan of action to eliminate the foul odors. If they don't comply, they could be fined.