DOWNERS GROVE – Stormwater regulations intended to significantly limit flooding caused by new residential construction in Downers Grove could be in place later this year.
Village staff will soon present to the construction community the new proposals, which have been worked on for several months.
The regulations are expected to come before the Downers Grove Village Council in May, and they could be on the books by the summer, Village Manager Dave Fieldman said.
The new regulations, which were reviewed at the April 3 Village Council meeting, require stormwater detention for all new single-family homes and major additions.
A major addition is defined as anything that expands the footprint of a house and alters 600 square feet of it.
Homes located within 200 feet of the public drainage system would tie into the system. Homes not able to make the connection would be required to provide a larger stormwater detention, Fieldman said.
He said stormwater management is a unique challenge in Downers Grove.
“There are parts of town that don’t have any stormwater management,” Fieldman said.
Downers Grove also has a lot of clay in its soil, he said.
"So we have a lot of issues of not being able to capture the water, and when it hits the ground, it goes underground, it doesn’t absorb in," Fieldman said.
Additionally, the village must strive to achieve a balance of allowing more residential development while not allowing the stormwater drainage from those developments to worsen the problem, he said.
The village has about 20 stormwater management projects on the books for the next several years, in addition to several maintenance jobs, Fieldman said. Twenty-five projects have been completed over the past decade, he said.
The village will continue to focus on private stormwater control, which will be funded by builders and property owners, while striving to improve the public system, Fieldman said.
“We are trying to retroactively integrate both systems,” he said.
The proposed regulations represent significant enhancement over current regulations, which are limited to rain gardens and dry wells, or small storage basins not connected to the drainage system.
However, the new requirements may be costly.
A homeowner could expect to pay between $15,000 and $30,000 to connect to the village system if it’s located in front of a house and as much as $35,000 to $50,000 if a line has to be extended to reach the system. Fieldman said.
There are four main reasons for the cost disparity: the length of the drainage pipe or ditch required, elevation differences between a home’s storage basin and the storage system, the need to remove trees or relocate utility lines, and the location of the village’s drainage system.
Downers Grove leaders continue to express full support for the new regulations but admit they will only solve part of the village’s flooding problem.
“This is a piece of a much bigger puzzle,” Mayor Martin Tully said.