By swimming the entire Green/Duwamish River in King County, Mark Powell hopes to show that the river’s full length — roughly 85 miles from the mountains to Puget Sound — is a single system worthy of protection and restoration.

I believe that most people have heard about the Duwamish Waterway in Seattle, a channelized, industrialized section of the lower Duwamish River where decades of pollution are being cleaned up, one step at a time. But how much does anyone know about the upper end of the river, which begins as a trickle of crystal clear water in the Cascade Mountains south of Snoqualmie Pass?

“Almost nobody knows the river well, not even the people who live along the river,” Mark told me.

Mark, the Puget Sound Program director for Washington Environmental Council. said the idea of swimming the entire river came to him during the kickoff of a new Green/Duwamish Watershed Strategy by King County and Seattle. The plan is to identify all the significant problems in the watershed (map, PDF 1.1 mb) and to increase restoration efforts where needed.

“I thought this would be an interesting way to connect with people,” Mark said. “I’m a guy who likes to get outdoors, so this is a personal commitment I could make.”

Mark swam around Bainbridge Island in the winter of 2008-09. ““By swimming the whole coastline, I’m not just diving to the pretty spots. I’m forced to look at the gross parts,” he told reporter Michelle Ma in a story for the Seattle Times.

So far, Mark has been swimming the upper and middle portions of the Green/Duwamish River. He said his biggest surprise is finding pockets of good habitat everywhere he goes.

Earlier this month, he was accompanied on the river by Sheida Sahandy, executive director of the Puget Sound Partnership, and Martha Kongsgaard, chairwoman of the partnership’s Leadership Council. A few days before they swam the river near Auburn, the Leadership Council approved new “vitals signs” indicators for “human health” and “human well-being” to emphasize the human connection to the Puget Sound ecosystem. See “Water Ways” July 30.

The human connection was still on Sheida’s mind when I talked to her about a week after her trip to the Green River. The most “eye-opening” part of the swim for her was the condition of “this incredibly beautiful natural element coursing through a very urban landscape.”

She saw evidence of people living along the river in less-than-desirable conditions, she said. There were barbecues and trailer houses but no suggestion that people had any connection to the river — except that some individuals apparently were using it as a toilet, she said.

“I haven’t quite wrapped my head around that, but it feels very right that we are considering human well-being,” she explained. “On the one hand is what we have done to the river. On the other hand is what we have done to ourselves. We need to figure out how it all links together.”

Mark’s adventures on the river are chronicled in a blog called “Swim Duwamish.” He hopes to swim every section of the river where he is allowed to go and be safe. A portion of the Green River controlled by the city of Tacoma has no public access, because it is a source of the city’s water supply. Rapids in the Green River Gorge are said to be dangerous, so Mark will look for a guide to help him. And because of heavy marine traffic in the Duwamish Waterway, he may use a boat to escort him on his approach to Seattle’s Elliott Bay.

The Green/Duwamish River may be the most disjointed river in Puget Sound, both physically and psychologically. People who have seen the industrialized lower river find it hard to visualize the near-pristine salmon stream spilling clean water down from the mountains. It is the upper part that provides the inspiration to clean up the lower part, Mark told me.

“If there was a reason for sacrificing a river, you could find it in the Duwamish,” he said. “But we can’t afford to sacrifice even one river. To me, this is what protecting Puget Sound is all about. By the time the pollution gets to Puget Sound it is too late.”

If salmon can make it through the gauntlet in the lower river, they may have a fighting chance to spawn and produce a new generation of Green River fish. Improving their migration corridor is not an impossible dream.

I suggested to Mark that the name of the river be officially changed to “Green/Duwamish” or “Green-Duwamish” to help people recognize that this is a single river from the mountains to Puget Sound. After all, the name “Salish Sea” has helped some people realize that we share an inland waterway with Canadians. The other name-change option would be to call it Duwamish all the way.

Until I started reading about the Duwamish, I didn’t realize how this river once captured water from the Black River and the White River as well as the Green River and the Cedar River. But the system has changed drastically over the past century or so.

As you can see in the map on this page, the Green River once joined the White River and flowed north, picking up waters from the Black River. The Black River, which took drainage from Lake Washington, picked up water from the Cedar River.

Where the Black River merged with the White River, it became the Duwamish all the way to Puget Sound.

Two major events changed the rivers’ flow and subsequently the nomenclature. In 1906, a flood diverted the White River to the south into the channel of the Stuck River, which flowed into the Puyallup River. Shortly after that, the White River was artificially confined to keep it flowing south. Because the river flowing north contained water only from the Green River, the name “White” was changed to “Green” downstream to where the Duwamish began.

The other big event was the construction of the Lake Washington Ship Canal in 1917 to connect the lake with Puget Sound. The construction lowered the lake by more than 8 feet, with the lake level controlled by the Hiram M. Chittenden Locks. The Black River, which had taken the discharge flow from Lake Washington before construction, then dried up. The Cedar River, which had flowed into the Black River, was diverted into the lake.

Following those changes, the Green River and the Duwamish became essentially the same river, with the total flow perhaps one-third as much as it had been before the changes. If you are interested in this history and other geological forces at work in the area, check out the 1970 report by the U.S. Geological Survey (PDF 53.1 mb).

Share on Facebook