Concrete pavers
Pervious concrete pavers in place in a Dubuque alley. (Image credit: City of Dubuque video)

Dubuque is the oldest city in Iowa. But when Jon Dienst took the city council on a trolley ride 10 years ago, it was not to admire historic sites. They looked at alleys.

Dienst is a civil engineer for Dubuque. He wanted to show the city council how to re-pave the alleys in a way that could help prevent flooding in nearby homes and businesses.

Dienst says the city faces increasingly heavy downpours.

“It’s been wreaking havoc in areas of downtown,” he says.

So the city council decided to start repaving its old alleys with interlocking concrete pavers. They look historic but have a modern twist: tiny holes that allow water to seep through into a layer of crushed stone.

“And that’s what holds and stores that water and then slowly releases it,” Dienst says.

He says that after the first six or seven alleys were completed, city residents began calling and asking to have their alleys re-paved, too.

“And so we got some momentum and we started getting interest,” he says.

Dubuque has now reconstructed about 80 alleys and plans to finish more than 200 within the next 20 years.

That’s expected to reduce stormwater runoff from the alleys by 80% – helping prepare the city for the future while maintaining its historic charm.

Reporting credit: Deborah Jian Lee/ChavoBart Digital Media.