For 1st Ward Alderman Diane Gutenkauf, installing a new eco-friendly, permeable driveway is about more than just replacing crumbling concrete.
The driveway needed to be replaced, and because the yard was subject to ponding in heavy rains, Gutenkauf and her husband thought this was a great opportunity to create a solution.
“It was the perfect combination of things,” she said.
During a normal rain, the water from the yard would run down the driveway to the street and along the curb until it hit the sewer.
“It’s like a little river, just flows down the driveway, which is, on the one hand, great because it drains the back yard,” Gutenkauf said. “On the other hand, it’s flowing into the streets, it hits the streets, it runs along the curb until it goes into the storm sewer. When you couple that with ... I thought, ‘Well since we need to replace the driveway anyway, let’s look at doing a permeable driveway.’ If everything works like it’s supposed to, the water from my back yard will hit the driveway and sink in."
Gutenkauf said it is important for people in Elmhurst to figure out ways to manage stormwater where it falls.
John Lockett, president of sales for C.R. Schmidt, the company that installed Gutenkauf’s driveway, said if everyone in Elmhurst had permeable driveways, it would make a big difference with stormwater issues.
“It would be humungous,” he said.
Removing the traditional driveway and installing a permeable driveway system costs about $15 to $20 a square foot. Gutenkauf's driveway cost $17,000 and took three days to install.
Lockett estimated that it would have cost about half that for Gutenkauf to install a new concrete driveway, but there are tradeoffs. The overall estimated lifespan for a permeable system is at least 30 years. That's about three times the life span of concrete, he said. And the materials, like the concrete pavers, have a lifetime guarantee.
Underneath the pavers, Gutenkauf’s driveway has 14 inches of a gravel base specifically designed for permeable systems, Lockett said. Beneath that is soil. With this system, the water doesn’t go into the street and it doesn’t go into the storm sewer.
“It actually contains itself,” Lockett said.
The permeable driveway has a 30 percent "void," which means that of the entire surface area of the driveway, 30 percent is not concrete pavers. It is that 30 percent that allows the water to seep through. The paver driveway also has 90 percent compaction, which means it has a hard, level base, despite the permeable areas. A solid concrete driveway has a compaction of 100 percent.
It's one way to start to take on the "troubling, ongoing issue" of flooding, Gutenkauf said. Many Elmhurst homes and streets were by extensive flooding caused by two massive storms last summer.
“It seems to me that anything we can do to help contain the water where it falls is really important, and we should try to do it," she said.
There are other problems with runoff besides the amount of water, Gutenkauf said. As the water drains into the storm sewers it drags everything from the street with it—oil, cigarette butts and chemicals—which eventually make their way into the rivers and creeks and pollute it.
There are many materials that can be used for the permeable surface, including granite and glass, Gutenkauf said. But after she and her husband researched it, they went with the concrete pavers because it is a more traditional look.
She said it's important for people to think of creative ways to solve problems, and flooding has been the city has faced. She hopes other residents will consider permeable driveways.
“It’s something I think we should be encouraging people to do, and (we should) figure out ways to make information available. And, if showing off how pretty it can be helps, I’m happy to do that," she said.