NPDES MS4 Phase I Permit - Clackamas Group
Oregon City's Stormwater Discharge Permit was reissued on September 15, 2021 and took effect on October 1, 2021. Oregon City is one of 12 co-permittees that comprise the Clackamas County Group. View the National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) Phase I Permit - Clackamas Group (PDF).
Oregon City's Stormwater Management Plan (SWMP) was updated and submitted to DEQ for review on November 30, 2022. View the 2022 SWMP NPDES Phase I Stormwater Management Program Document (PDF).
The Stormwater Management Plan (SWMP) implementation requires numerous:
- Guidance manuals
- Other related documents
Throughout the City's current SWMP, the relevant documents are noted within each program category or best management plan (BMP). The referenced documents have been compiled into the SWMP Document Library.
Department of Environmental Quality
The OR Department of Environmental Quality (DEQ) regulates stormwater runoff from the City of Oregon City through the NPDES MS4 Discharge Permit, issued to Clackamas County and its co-permittees:
- City of Oregon City
- City of Lake Oswego
- City of Gladstone
- City of West Linn
- City of Milwaukie
- City of Wilsonville
- City of Happy Valley
- City of Johnson City
- City of Rivergrove
- Oak Lodge Water Service District
- Clackamas County
- Water Environment Services
Additionally, DEQ has set Total Maximum Daily Loads (TMDL) for water bodies located in the Willamette River Basin. Currently there are 3 parameters of concern: temperature, bacteria, and mercury. A TMDL Implementation Plan is required to address these parameters. Oregon City's SWMP serves as the implementation plan for bacteria and mercury, and our TMDL Implementation Plan addresses temperature.
Each co-permittee is required to submit an annual report to DEQ summarizing accomplishments and implementation of the individual SWMP. TMDL Implementation Plan activities are reported in an annual TMDL Progress Report.
Please visit the NPDES Annual Reports page to view these Reports.
- National Pollutant Discharge Elimination System Phase I Stormwater Management Program, November 2022 (PDF)
- National Pollutant Discharge Elimination System Municipal Separate Storm Sewer System Phase I Permit - Clackamas Group, November 2021 (PDF)
- Total Maximum Daily Load Implementation Plan, August 2020 (PDF)
- Macroinvertebrate Assessment, 2019 (PDF)
- National Pollutant Discharge Elimination System Municipal Separate Storm Sewer System Permit Renewal Application 2017 (PDF)
- Stormwater Monitoring Plan, January 2017 (PDF)
- Total Maximum Daily Load Implementation Plan, May 2014 (PDF)
- Macroinvertebrate Assessment, February 2014 (PDF)
- Stormwater Program PowerPoint Presentation, March 2013 (PDF)
- Association of Clean Water Administrators Trends Memorandum, October 2007 (PDF)
- Final Interim Evaluation Report, May 2006 (PDF)
- Qualitative Assessment of Changes in Pollutant Loads, July 2005 (PDF)
- Association of Clean Water Administrators Rangers Memorandum, May 2005 (PDF)
- OR Department of Environmental Quality Final Guidelines for Chlorinated Water Discharges, May 1997 (PDF)