Washington State's Stormwater Management Program

Abstract

To comply with state and federal laws, the Washington State Department of Transportation developed a Stormwater Management Program. The program included an outfall inventory and retrofit program, a Highway Runoff Manual (HRM), and stormwater research. Field crew inventoried sites where highway stormwater runoff is collected and discharged to surface water, ground water, and municipal storm sewers. Pipes, ditches, and stormwater structures that provide quantity and quality control were inventoried. The screening assessment for potential water pollution problems was made via observation and sampling kit. The sampling kit was found to be ineffective at identifying illicit connections. Inventoried sites were mapped using global positioning and geographic information system technology. Research was conducted on sites to determine watershed characteristics, potential environmental effects, and Best Management Practice (BMP) retrofit options. A computer data base of information is maintained to facilitate stormw...