Portland Leads in Green Stormwater Infrastructure to Combat Runoff and Improve Water Quality
Portland, Oregon, has established itself as a national leader in implementing green stormwater infrastructure (GSI) to manage rainwater runoff. The city's approach integrates natural elements such as rain gardens, ecoroofs, and soil filtration systems to reduce the volume of stormwater entering its combined sewer system. This initiative is a direct response to a 1991 mandate from the Oregon Department of Environmental Quality, which set a 20-year deadline for Portland to significantly decrease combined sewer overflows. The city's GSI efforts have resulted in a 35% reduction in stormwater volume directed to the combined sewer and the removal of 1.2 billion gallons of stormwater annually through over 56,000 disconnected downspouts. Approximately 40 green street installations are added each year, and property owners can receive up to a 35% discount on their stormwater utility bills through the Clean River Rewards program for maintaining GSI features.
