Stream restoration becomes a showpiece
September 23, 2008
By Jon Savelle
It can’t be seen from the street, but the presence of earthmoving equipment near Southeast 43rd Way is a clear hint that something big is happening in the trees on the south side.
That something is a large wetland and stream restoration project, part of The Dwelling Co.’s Mallard Bay development that also includes a complex of townhouses going up on the other side of Southeast 43rd Way.
The Planning Department recently announced completion of some major milestones for the restoration, including the rerouting of Many Springs Creek, elimination of an access road and parking, and demolition of abandoned buildings on the site. The property occupies the southeast corner where Southeast 43rd Way connects to East Lake Sammamish Parkway Southeast.
Planners have two goals for the restoration. One is to provide high quality wildlife habitat on the northern edge of the city. The other is to moderate seasonal flooding along Southeast 43rd Way.
To achieve this, Many Springs Creek was shifted 150 feet south. Contractors created a new, rocky streambed with pools, logs and riffles that meanders in picturesque fashion through stands of alder, cottonwood, willow and hemlock.
Below the restored area, the creek enters a Category 1 wetland, the highest rating possible and the only one of its type in Issaquah.
The size and quality of the project is highly unusual, said city Wetland Biologist Kirk Prindle. And it hasn’t happened without struggle. Much time and effort was expended in developing the plan with wetland consultants Talasaea and working out construction staging — particularly since the developer’s original intent was just to bulldoze and replant.
“We made it a priority that they save every single native tree,” Prindle said.
That was accomplished by heavy-equipment operators with Aero Construction, who seemed to be artists with trackhoe and bulldozer: After using them to yank out invasive weeds, grade the soil and excavate a new stream channel, every native tree was indeed untouched.
“I’ve never seen people work with big machines like this and do such a nice job,” Prindle said.
Right now, the project still looks raw. Bare dirt is the main thing underfoot, but soon it will be replanted with native species. When finished, it will be a forested shrub-scrub habitat, a showpiece property on the city’s north entrance that should attract wildlife and people, too. Already, it has attracted attention from state agencies for its design and execution.
“It was a struggle, but now I’m kind of proud of it,” Prindle said.
He said he’s also proud of the way multiple city departments and state agencies cooperated to pull it off. Among them were the city’s Public Works Engineering, Planning and Building departments, plus the state departments of Fish and Wildlife and Ecology, and the U.S. Army Corps of Engineers.
Putting it all together in one place, with a Category 1 wetland to boot, is virtually unheard of, Prindle said, adding that he believes that, once the planting takes hold and weed removal is complete, the natural system should rebound spectacularly.
The restored Many Springs Creek joins Laughing Jacobs Creek in the wetland, which is just a culvert and creek away from Lake Sammamish and its native kokanee salmon.
The fish live their adult lives in the lake and spawn in surrounding streams. But urbanization has taken a toll on them, with one run extinct and others declining.
“It’s very exciting,” Prindle said. “We have the potential to get kokanee.”
Reach Reporter Jon Savelle at 392-6434, ext. 234, or email@example.com.