Sewer project to disrupt traffic in downtown Des Moines

Downtown Des Moines is going to look much different next year, due in part to a $29 million sewer project through much of MLK Parkway.

What's happening: The city is starting to alert nearby businesses and city event planners about the DSM Metropolitan Wastewater Reclamation Authority (WRA) project, which is slated to get underway in the coming months.

Why it matters: Construction will close some of downtown DSM's busiest streets for almost a year.

• "This is going to be very disruptive and you're going to hear a lot about this project," WRA director Scott Hutchens warned the City Council last month.

Details: The WRA's Ingersoll Run project is a sewer separation, stretching from around 22nd and High Streets, through a section of Locust Street and along MLK from 15th Street to Principal Park.

• Groundwork begins in January, and the completion date is anticipated to be around June of 2024.

Between the lines: Modern sewers are typically built so that raw sewage is carried in a separate line from rainwater runoff.

• Some of DSM's sewers are more than 100 years old, and the city had 20 systems with combined lines. That's a problem because they can exceed capacity and discharge untreated wastewater into rivers or streams.

Flashback: The project is part of an agreement DSM made with environmental regulators back in 2003 to continue operating the WRA facility on the city's southeast side.

• The following year, DSM started citywide sewer separations under a five-phase, $338 million plan that's expected to continue for another four years. Ingersoll Run is one of the last projects.

Of note: DSM is the only city in the metro with combined sewers, and regulators have agreed to keep one downtown because it's too costly to separate.

• Thirteen others in Iowa, mostly river towns, are dealing with similar issues.
• Nationally, there are 772 cities with such systems, according to the Environmental Protection Agency.