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 Water Quality Permit Program

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NPDES Stormwater Discharge Permits - Phase I Municipalities (MS4)

A municipal separate storm sewer system (MS4) is a conveyance or system of conveyances (e.g., roads with drainage systems, municipal streets, catch basins, curbs, gutters, manmade channels or storm drains) owned or operated by a governmental entity that discharges to waters of the State.  Sources that need to obtain an MS4 permit are classified as either "Phase I" or "Phase II". Phase I MS4s are those with populations greater than 100,000, while regulated Phase II (or "small") MS4s serve populations less than 100,000 located within Census Bureau-defined Urbanized Areas. Federal regulations also provide EPA and the states the discretion to require other MS4s outside of Urbanized Areas to apply for a permit.

Clackamas County Group - Public Notice for Permit Reissuance

The proposed permit action addresses the appeal of the MS4 permit previously issued on Mar. 15, 2011. DEQ will accept public comments until 5 p.m., Jan. 13, 2012. For more information, see the public notice.

Clackamas County Group Co-Permitees: Clackamas County DTD, City of Gladstone, City of Johnson City, City of Lake Oswego, City of Milwaukie, City of Oregon City, City of West Linn, City of Wilsonville, Oak Lodge Sanitary District, CCSD #1, City of Happy Valley, SWMACC and City of Rivergrove

  • Stormwater Management Plans

Multnomah County - Public Notice for Permit Modification

The proposed modification is related to the NPDES permit renewed on Dec. 30, 2010. DEQ will accept public comments until 5 p.m., Jan. 13, 2012. For more information, see the public notice.

MS4 Phase I NPDES Permits

Portland Group
    Reissued January 31, 2011

Multnomah County, Gresham Group, City of Salem, City of Eugene
    Reissued December 30, 2010

Clean Water Services
     Modified on reconsideration - Issued July 27, 2005

Willamette Basin Mercury Monitoring

Willamette Basin Mercury Monitoring Memo PDF (This memo applies to Multnomah County, Gresham, Eugene, Salem and Portland MS4 permits.)
Mercury (Hg) data is needed from MS4 permittees in the Willamette Basin to complete Phase 2 of the Willamette Hg Total Maximum Daily Load (TMDL). DEQ incorporated this data collection into monitoring requirements in Schedule B of the renewal permits. Monitoring and analysis for mercury and methyl mercury must be conducted in accordance with DEQ’s December 23, 2010 “Mercury Monitoring Requirements for Willamette Basin Permittees” memo.

 
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For stormwater-related questions, contact the appropriate DEQ regional office.

For general information about NPDES Stormwater Discharge Permits, contact Benjamin Benninghoff by phone at (503) 229-5185 or by e-mail .

Oregon Department of Environmental Quality
Headquarters: 811 SW Sixth Ave., Portland, OR 97204-1390
Phone: 503-229-5696 or toll free in Oregon 1-800-452-4011
Oregon Telecommunications Relay Service: 1-800-735-2900  FAX: 503-229-6124

The Oregon Department of Environmental Quality is a regulatory agency authorized to protect Oregon's environment by
the State of Oregon and the Environmental Protection Agency.

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