A Talk on the Wild Side.
|With many partners, the Service's Paul Bakke is restoring a creek in Seattle. Photo Credit: Ann Froschauer/USFWS|
When Service geomorphologist/hydrologist Paul Bakke was growing up in northwest Seattle, his parents told him to stay away from the neighborhood’s polluted Thornton Creek. “Nobody wanted their kids playing in that creek.”
So of course, he and his friends played in it. “It was sort of this fascinating little universe of things going on,” he says, adding that he has “lots of fond memories of it even though it wasn't by any means a pristine water body.”
Paul still finds Thornton Creek fascinating, but now he is helping restore a part of the creek right near where he went to high school into a salmon-spawning stream … in the middle of Seattle, among the largest metro areas in the nation.
It hasn’t been easy.
|Among the partners is Katherine Lynch, the senior environmental analyst with Seattle Public Utilities (holding plans). Photo Credit: Ann Froschauer/USFWS|
The creek where they are working had been artificially modified over the years, “made into a narrow rock-lined ditch basically,” Paul says.
Urban stream restoration tends to be difficult and controversial because the presence of people often means that the streams have been heavily changed. Lack of available land and the higher costs in a city environment limit urban restoration. This is true in Seattle, which was the top-growing big city in 2013. When compared with restoration in a rural environment, critics say you don't get a lot of fish for your dollar.
But, as Paul says, an urban stream restoration puts “this showpiece right in people’s backyards literally.”
The people living in the Thornton Creek watershed can see the restoration happening, see the work going into it, and see the resulting fish and how different the restored stream is from other parts of the creek, some of which remain polluted.
|The team created a new streambed, which had not been done before in the United States. Photo Credit: Ann Froschauer/USFWS|
“It’s a huge educational opportunity and outreach opportunity to have this,” Paul says, that’s “going to bring a lot of people in that otherwise might have not even thought about stream restoration.”
With that in mind, Paul and the team, which included Seattle Public Utilities and Natural Systems Design, an engineering consulting firm specializing in stream restoration, “went the extra mile and did some things here that don't usually get done in a restoration project or particularly in in an urban restoration project.”
In fact, what they did was a first-of-its-kind project in the United States.
Along with rebuilding the stream channel and floodplain, the team created a new streambed. They “brought in fresh, clean gravel and built a new streambed so that water can circulate deeply beneath the surface of the streambed and back up again, numerous times.”
A good streambed for water underneath the surface to flow through is important, Paul says, because the gravel and rocks and the rest of the streambed – bacteria, algae, insects, juvenile fish and more – act as a “big chemical reactor,” cleaning and cooling the water, filtering excess nutrients and enabling salmon to lay their eggs in it.
|A new streambed takes a lot of work. Photo Credit: Ann Froschauer/USFWS|
The new streambed, along with other factors like the shape, size and path of the channel, will help the stream maintain balance or equilibrium – meaning “you have roughly the same amount of gravel and sand going out as comes in,” Paul says. Streams with a good balance “can exist in good condition for many years without artificial maintenance,” he says. If a stream is out of balance, “you are always fighting” to get it, he says.
Paul hopes and believes that the balance and proper channel shape will mean success for spawning Chinook or “king” salmon, a federally protected species. Before, kings would try to spawn in the creek, but “winter storms would wash the eggs all out because the stream channel wasn't the right shape to have that kind of habitat.” Now, “they will have places that are just right,” says Paul, who has invented several cutting-edge systems to monitor sub-surface streambed health. He is now installing those monitors, and if all goes according to plan, he’ll see kings return and successfully spawn.
Principal Engineer Rocky Hrachovec of Natural Systems Design, the project manager for the restoration, deserves a lot of credit, Paul says.
He is the one, Paul says, who took the conceptual designs for the streambed and made them into reality, with such habitat features as corner and pocket pools.
|Paul hopes king salmon will use the restored stream to breed. Photo Credit: Ann Froschauer/USFWS|
Hrachovec is confident of the new streambed. The chief concern, he says, is tiny bits of sand or gravel clogging up some of the streambed features, but he believes the water will be able to circulate “for many years to come.”
Katherine Lynch, the senior environmental analyst with Seattle Public Utilities, has been working with Paul on restoration projects in Seattle for 10 years and is confident of Paul’s design, too.
The design was strong when Paul showed it to the team, she says, “and now that it is constructed and we are seeing water flowing through it, so far it looks really good.”
Paul started out as a seasonal park ranger and naturalist, then became an engineer. He enjoyed the physical science of engineering - hydraulics, for instance - but missed a connection to the natural world. In Paul’s words, his career as a hydrologist/geomorphologist “straddles that fence between the physical science and the ecological science, and focuses on the natural world and the outdoors.”
That multi-faceted career helps Paul shine. Says Lynch: Paul brings a “really broad base of experience to his design I think that makes them quite unique.”
Hrachovec agrees that Paul’s experience is a big plus. “Paul brings his enthusiasm for good science and insight based on years of field experience to projects.”
What stands out for Lynch is Paul’s dedication. “He's extremely committed to the project; you know you can totally rely on him,” she says.
|Paul confers with Principal Engineer Rocky Hrachovec of Natural Systems Design, the project manager for the restoration. Photo Credit: Ann Froschauer/USFWS|
For Hrachovec, it’s Paul’s “insight and his sense of humor.”
Paul attributes much of his love of water to his dad, an avid fisherman. But it’s more than fishing. “There's something about moving water that's magical.”
Maybe that magic keeps him dedicated, and with his help, the Service and partners are working hard to make sure a new generation shares some of that magic, even in cities.
-- Matt Trott, External Affairs