By Anne Marie Amacher
DAVENPORT — Efforts to stop persistent flooding of the Cosgrove parking lot on the St. Ambrose University campus and along Locust Street in front of the university are underway.
Work on the $1.9 million project that is a cooperative effort of St. Ambrose and the City of Davenport started last week and is expected to be done by Aug. 15, said Jim Hannon, the university’s physical plant director.
Hannon said flooding has occurred for several decades and the city and university have been working together for about 10 years to work out a solution. “We joined forces, have done studies and are working on corrective measures,” Hannon said.
The flooding has been due to a “grossly undersized storm drain” and construction in the neighborhood over the decades (both on campus and off campus).
The two groups have been working on a master plan and when a grant became available to help offset costs, the plan was a go. A $400,000 grant from Watershed Improvement Board of the Iowa Department of Agriculture and Land Stewardship was awarded to the city. The remaining cost for the project is being paid for by the city and St. Ambrose. The city will pay about $650,000 and St. Ambrose will pay about $800,000.
“There are 63 (total) working days for this project,” Hannon said last week.
The first phase of the project is to remove the pavement from the entire Cosgrove parking lot. From there, four to six feet of dirt will be removed. A detention system will be installed so water goes under the lot instead of on top, Hannon noted. The lot will be resurfaced when the project is complete. The city also is doing storm sewer work on Locust and Scott streets.
The detention system will hold about 1 million gallons of rainwater. “That’s enough to hold a 10-year storm event, which is 7.1 inches in a 24-hour period.”
An overland path will route water toward the middle of campus as well, which is essential to helping alleviate the problem, Hannon said. An underground pipe will direct water underground to an area north (or behind) Ambrose Hall. That part of the project also is underway at this point.
Although the new parking lot will actually be lower than the existing one, Hannon said some areas will be pitched to direct the water to the detention storage. Green areas will be added to the parking lot and along Locust Street as well.
Over the past few years, various practices have been implemented to capture and store rainwater so it would not add to the already overwhelmed storm sewer system. Hannon said the water stored in retention tanks is used on campus to water grass, flowers and to clean the campus.