Low Impact Development in the Highway Runoff Manual

Washington State Department of Transportation

	Select photo to view in larger scale Workers install Eco-Stone® permeable pavers at a municipal park and ride in Marysville. The Washington State Department of Transportation is considering using permeable pavement, such as Eco-Stone®, at its park and rides and on pedestrian paths.
	Select photo to view in larger scale Eco-stone detail

Description
The Washington State Department of Transportation is currently revising its 1995 Highway Runoff Manual. As part of this revision, the department will develop and reference three low impact development elements in the revised manual:

1. Permeable paving at park and rides, pedestrian paths, and lower speed roadways.

2. Bioretention along roadways.

3. Constructed wetlands for stormwater treatment.

The LID portion of the revised manual should be available for use by the end of September 2003 and will include plans, specifications, methodology for estimating costs, and a hydraulic design process.

Contacts
Rick Johnson
Washington State Department of Transportation
(260) 440-4642
johnsor@wsdot.wa.gov

Larry Schaffner
Washington State Department of Transportation
(360) 570-6657
schaffl@wsdot.wa.gov
Website:
www.wsdot.wa.gov/fasc/
Follow the links to:
>Engineering Publications
>On-Line Technical Manual Library
>Highway Runoff Manua