The Source of the Duwamish River

June 15th, 2015

The headwaters of the Duwamish River are not easy to find.  Start with a map and you’re in trouble—you need some local knowledge first.  The Duwamish River is called the Green River upstream from the Seattle Sounders’ practice field in Tukwila.  In a strange twist, the White River used to be the source of the Duwamish before farmers and flooding diverted the White River south to Tacoma in the early 1900s.

The Duwamish River begins as the Green River in the mountains southeast of Seattle.  Fly east from SeaTac airport and you’re above it in minutes.  But if you want to touch the water, you’ll face a long drive on bumpy gravel roads.  The actual headwaters require a hike of several miles along the Blowout Mountain and Pacific Crest trails.

I drove 2 hours from Seattle and hiked another half hour to reach the slopes above the Green River.  I found the source of the Duwamish, some wet seeps near 5000 feet elevation on the west-facing slopes of Blowout Mountain. There will be no swimming today.  I was wondering if there would be a pool big enough to get in, but the river starts small and on this hot afternoon it’s little more than wet spots and a trickle.

Looking down the valley, the top of the Green River flows through a lovely forested valley.  There are few signs of people other than some logged areas and some roads.  Just uphill, the Pacific Crest Trail separates the Green River drainage from the Yakima drainage to the east.

How many people in the Seattle area know that the headwaters of Seattle’s Duwamish River are this beautiful and serene?  Water that enters the Green River up here is taking a path that has changed little since the last ice age.  There could not be a more dramatic contrast with the other end of the river where the Duwamish enters Puget Sound.  I’m eager to get in the water and explore the changes downstream.