BES Columbia Slough Stormwater Retrofit Inventory

In January 2010, GreenWorks and BES staff conducted intensive field work locating and documenting potential locations for stormwater facilities throughout the Columbia Slough Watershed in North Portland. The Columbia Slough has been designated a high priority area by the City of Portland for improving watershed health and reducing pollutants. The project team focused on four target areas where green street facilities would maximize stormwater quality treatment and capture contaminated sediment before being discharged into the Slough. Each potential green street facility was ranked based on its potential performance, feasibility, and cost. GreenWorks assisted BES in project prioritization and provided an overall ranking using Geographic Information Systems (GIS). Over 150 potential green street facilities were identified, which would potentially result in stormwater treatment from over 35 acres of impermeable surfaces.