Zoning & Building Safety:

Zoning and Building Safety Department
Stormwater Management

Low Impact Design (LID) Strategies


Basic LID strategy for handling runoff is to: 1) reduce the volume of runoff and 2) decentralize flows. This is usually best accomplished by creating a series of smaller retention/detention areas that allow localized filtration (rather than carrying runoff to a remote collection area) in conjunction with facilities addressing larger storm events as required. Common methods include:

  • Bioretention Cells/Rain gardens
  • Vegetated Swales
  • Filter Strips
  • Disconnected Impervious Areas
  • Cistern Collection Systems

Decreasing Impervious Sur faces can be a simple strategy to address water quality and avoid problems from storm water runoff and water table depletion, by reducing surfaces that prevent natural filtration. Methods may include:

  • Reducing Roadway Surfaces
  • Permeable Pavement Surfaces
  • Vegetative Roof Systems (Green Roofs)

Cost benefits to builders and developers utilizing LID strategies can be significant. According to the Center for Watershed Protection, traditional curbs, gutters, storm drain inlets, piping and detention basins can cost two to three times more than engineered grass swales and other techniques to handle roadway runoff. Choosing permeable pavement for a parking area may remove the need for a catch basin and conveyance piping. Small distributed filtration areas on individual lots can reduce site requirements for larger detention ponds that take up valuable land area.

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Rock Island County Office Building (map ExternalLink.gif)
1504 Third Avenue, Room 305, Rock Island IL 61204-8624
Phone: (309) 558-3771      Fax: (309) 786-4456

      Hours: 8:00 AM to 10:00 AM and 3:00 PM to 4:30 PM - Monday thru Friday
Inspectors are in the field from 10:00 AM until 3:00 PM