The MSOE Pervious Parking Lot (located on North Milwaukee, next to RWJ Residence Hall) slows and removes pollutants in overland runoff from a large parking lot. A pervious, or porous, parking lot allows water to flow through it into the ground below. Before the project was constructed, the runoff flowed directly into a combined sewer. By holding back runoff, MSOE is helping to reduce the amount and frequency of sewer overflows.
On pervious pavement, rainwater passes through the pavement, entering an 18 inch thick layer of crushed stone. It then soaks into native soils, mostly sand and gravel, or seeps slowly into a drain tile that runs along the lower edge of the parking lot.
This parking lot contains two different types of pervious pavement. Pervious asphalt tops the south two-thirds. Pervious concrete tops the north one-third. Driveways have standard asphalt. Pervious pavements are created by eliminating much of the fine material from the mixes and applying special admixtures. Pervious pavements have a much rougher texture than standard pavements. This project is testing the pervious pavements performance including permeability, durability, maintenance needs, installation and winter performance.
In fall 2004, the Milwaukee Metropolitan Sewerage District selected MSOE’s Pervious Parking Lot for funding as a storm water Best Management Practices demonstration project. Best Management projects are those that use innovative ways to solve environmental problems. The project development team included TEI Corp., a local environmental engineering firm that designed and constructed the project. MSOE is documenting the project’s environmental effectiveness. Professor Willie Gonwa, P.E. is the principal investigator.