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Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

MAILING ADDRESS: 1120 SW 5th Ave, Room 1000, Portland, OR 97204

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California Subwatershed Facts

  • The subwatershed consists of 267 acres in southwest Portland.
  • Purple martins have been observed in the vicinity of Willamette Park.
  • There are 1,378 feet of open stream channels in this subwatershed.
  • Thirty nine acres of the subwatershed are parks and open space, 46 acres are in public ownership.
  • About half of this subwatershed is impervious area, mostly streets.
  • Willamette Park provides stop-over habitat for osprey, hawks, herons, and neo-tropical migratory birds.
  • Forty one acres of the subwatershed are forested.
  • Thirty nine acres of the subwatershed have woodland type tree canopy.
  • One perennial creek and several seasonal creeks originate in George Himes Park near Terwilliger Parkway and flow to a combined sanitary and stormwater pipe near Interstate 5.
  • The forested areas and streams of the subwatershed provide an important link between the West Hills and the Ross Island-Oaks Bottom ecosystem complex to the east, and between Marquam Nature Park to the north and Tryon Creek State Natural Area to the south.