How "ghost streams" affect flooding in Detroit

(CBS DETROIT) - Flooding is becoming more of an issue as the climate crisis worsens in the U.S., especially in cities with aging infrastructure, like in Detroit.

However, in addition to the infrastructure, remnants of old waterways, known as "ghost streams," also contribute to flooding issues in some areas.

Jacob Napieralski, a professor of geology at the University of Michigan-Dearborn, is the author of a study that examines Detroit's buried waterways and joined CBS News Detroit to discuss how they impact flooding in the city.

These "ghost streams" are rivers and wetlands that used to be part of the landscape but were removed due to developments. The remnants are still there but have been buried.

These waterways had to be removed to build Metro Detroit, but Michigan is a water-rich state, and since wetlands are always wet, flooding is normal.

"So, as part of that early developments, we devalued rivers, we removed them from landscape, and there's quite a few," said Napieralski. So, the city of Detroit lost about 85/86% percent of their rivers since 1905."

This means that even though Detroit currently doesn't really have rivers, Napieralski said there used to be a lot in the past.

However, burying the waterways has a long-term impact.

If there are many concrete developments, the water doesn't have anywhere to go and will collect in these structures.

Napieralski used the Jefferson-Chalmers neighborhood of Detroit as an example. He said that since the neighborhood is comprised of buried wetlands, many residents often end up with flooded basements.

"There's been a number of studies that show communities that were scored poorly; in other words, bad investments for bankers and lenders, it's very difficult for residents to get loans," said Napieralski.

A poor score means that individuals living in the area have a higher chance of public and environmental health issues. These affected areas are typically low-income areas and areas where many residents don't speak English as their first language, according to Napieralski.

He said it's important that the public is informed about the impact of "ghost streams," and he's working on creating digital maps that inform residents about whether they live on buried waterways and tell them what the risk of flooding is in their neighborhood.

Even though some areas are prone to flooding, updating a city's aging infrastructure can be really expensive. People often have to be proactive about addressing flooding by investing in pumps to get water out of basements and by building rain gardens, for example.