Stormwater Management

Stormwater from urban areas that discharges to streams is managed under the Oregon Department of Environmental Quality (DEQ) National Pollutant Discharge Elimination System Stormwater Permit (NPDES).  Stormwater that is infiltrated into shallow wells is managed under the DEQ Underground Injection Control Permit (UIC).

NPDES Stormwater Program

PUBLIC COMMENT now accepted on the 2018 NPDES Stormwater Permit Annual Report through October 31, 2018 at 5:00pm at waterquality@multco.us or mail to Multnomah County Water Quality, 1620 SE 190th Ave, Portland OR, 97233. Download draft report below:

UIC Stormwater Program

Design and Construction Manual

Pollution Reduction

The County minimizes impacts from Road Operations to protect endangered fish species, including coho and Chinook salmon, and steelhead trout using the Road Maintenance and Operations Manual.  The County also reduces specific pollutants from streams in the unincorporated areas through a Total Maximum Daily Load Program.

TMDL Program

Fish Related Reports

Three rainbow coho in a water-filled container with a ruler.
Click through to see the full photoset of the Beaver Creek Fish Survey.
During fish surveys in Beaver Creek and Johnson Creek, biologists found 16 different native fish species, including endangered coho salmon and steelhead trout.
Five baby coho in a water-filled container.
Click through to see the full photoset of the Johnson Creek Fish Survey.