Municipal Stormwater Permit

NPDES Permit Background

On behalf of the community, the City of Eugene manages the municipal stormwater system which is the publicly owned system of gutters, curb inlets, manholes, stormwater treatment facilities (rain gardens, swales), pipes, and ditches that ultimately discharge to receiving waterbodies including Amazon Creek and the Willamette River. Like many other cities and counties in the United States, Eugene is required under the federal Clean Water Act to obtain a National Pollutant Discharge Elimination System (NPDES) permit for discharging stormwater runoff from the municipal stormwater system into the nation’s rivers and streams. The permit, administered by the Oregon Department of Environmental Quality(DEQ), is aimed at protecting and improving water quality and requires implementation of a broad range of stormwater pollution reduction measures as documented in a Stormwater Management Program Document. The permit also requires water quality monitoring as documented in a Monitoring Plan.

The City has been implementing stormwater pollution reduction measures since its first NPDES permit was issued in 1994. The permit has been re-issued three times since then: in 2004, 2010, and most recently September 2021. With each iteration of the permit,  and at certain times between the issuance of permits, an updated Stormwater Management Program Document and Monitoring Plan are required to ensure continued compliance with changing regulations and to reflect improved program effectiveness through adaptive management.  

Stormwater Management Program Document 

The current Stormwater Management Program Document (referred to as the "SWMP"), updated most recently in November 2023, is a written summary of the comprehensive set of 23 best management practices the City is implementing each day to meet the current NPDES permit and reduce stormwater pollution to the maximum extent practicable. Best management practices include: performing maintenance of the system of publicly-owned pipes, ditches, bioswales, rain gardens, and open waterways, street sweeping, seasonal leaf pick-up, winter road sanding and de-icing, erosion prevention for construction sites, water quality standards for new development and redevelopment, stormwater outreach and inspection of commercial and industrial sites, spill response, addressing illicit discharges and activities, stormwater education, volunteer activities, tree planting, and stormwater capital improvement projects. 

Stormwater Monitoring Plan

The current Stormwater Monitoring Plan describes the City’s monitoring objectives, strategies, sampling locations, pollutant parameters, and monitoring procedures and protocols.