Residents of the flood prone Dimmitt's Grove neighborhood of Bloomington have helped design a new rain garden to mitigate flooding and improve water quality.
Members of the community gathered on Tuesday at 506 Gridley St. for an official groundbreaking ceremony.
A companion project broke ground June 15 in Sunnyside Park.
This project represents cooperation across many groups, including Illinois State University, the Bloomington-Normal Water Reclamation District [BNWRD], the Dimmit's Grove Neighborhood Association, Farnsworth Group, Ecology Action Center and more.
"The people of Dimmit's Grove really played an integral role in the design here," said Joan Brehm, co-director of the Center for a Sustainable Water Future at Illinois State.
"We had focus groups, we did survey work, getting their feedback on what their questions were, what their concerns were, what elements of the rain garden were important to them, the things that they wanted to see," Brehm added. "So we really hope this will reflect your own vision for your neighborhood."
When rainwater flows through a community, it picks up various pollutants, said Emily Jenkins, senior engineering manager at Farnsworth Group, a Bloomington-based architectural and engineering firm.
The landscaping of the rain garden has been designed to filter the runoff through various plants and soils. This leads to cleaner water entering the sewer system, said Jenkins.
An important feature of the project is the "green alley."
"It will have permeable pavers with small spaces between to allow the water to flow through between the pavers to an underground storage area," said Jenkins. "This rain garden is going to reduce the runoff by 75%, so that's a big deal. That's a lot."
The underground storage area will be 9,000 cubic feet -- the size of an Olympic swimming pool, said Tim Ervin, executive director of BNWRD. From the underground storage area, the water will infiltrate into the ground.
"Essentially what we're constructing here is a place for storm runoff to flow to during intense periods of rainfall," said Ervin. "It's going to utilize the natural environment — the plants, the soil — and as the water is absorbed into the soil and into the green alley, it's going to help remove pollutants and various other types of chemicals before it enters the sewer system."
This is just one step in a larger effort to protect Bloomington's water quality, said Ervin, noting BNWRD also focuses on educating the community about water.
"Each project we do, each child we teach, we're preparing the future to deal with, truly, one of our greatest challenges in McLean County, which is water," he said.
