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Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Avenue, Suite 1000, Portland, OR 97204

Willamette Watershed

watershed photos



The Willamette Watershed includes Forest Park, downtown Portland, industrial districts on both sides of the river, and the city’s most densely populated residential neighborhoods. It extends from near Sauvie Island to just north of Lake Oswego and from the West Hills to the suburban neighborhoods east of I-205.

Southwest Watershed Resource Center

Resource center programs and resources

Willamette River Basin

Oregon's largest watershed

Willamette River History

How the Willamette River developed

Willamette Subwatershed Improvement Strategies

Actions for watershed health

Westside Streams Water Quality and Trend Analyses Status Report

2010 Technical Memorandum (PDF Document, 11,721kb)

Portland in 1852

An early map of Portland

Heartbleed Security Notice

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