In October 2014 the flame ash street trees along 35th Ave NE are showing their autumn colors. Since June 2014 street signs have been posted to warn drivers along the arterial that 35th Ave NE is closed to through-traffic at NE 107th Street where construction is underway at The Confluence. The Confluence is the place at NE 107th Street where the North and South Branches of Thornton Creek converge. At that lowest point in the roadway, stormwaters have often flooded surrounding streets and houses. This year of 2014 is the third phase of construction at The Confluence to add capacity for water and improve the environment for fish.
The Confluence work in 2014 has been to reconfigure a section of the South Branch of Thornton Creek to widen it, create meanders to slow the flow of water and improve habitat for fish. The in-water creek work had to be finished by the end of September to comply with Washington State regulations on fish habitat. In the photo below, on the west side of 35th Avenue NE looking toward Nathan Hale High School we see the improved creekbed. The banks of the creek which were formerly choked with vegetation are being replanted with new but smaller trees and shrubs.
On the east side of 35th Ave NE a floodplain is still under construction. In addition to the creek channel which flows into Meadowbrook Pond, overflow areas are being created so that stormwaters will not flood surrounding streets and houses. An artwork piece called Memory Tree stands in the floodplain to represent trees on the site which had to be removed, and symbolize the close connection to nature in Meadowbrook.
When completed, 35th Ave NE at NE 107th will have a bridgelike appearance. It will be slightly elevated which will alert drivers to slow down. Pedestrians will be able to see out over the floodplain with the creek flowing through it. Farther east of 35th Ave NE is the Meadowbrook Pond, a detention area where sediments filter out of the water. The water going downstream can be held back and controlled so that, on its way to its outlet at Matthews Beach into Lake Washington, Thornton Creek will not overflow.
The photo at left shows the progress of work as of August 2014, which may be compared to the above photo of October.
Since June 2014 the road has been closed at NE 107th Street for the Confluence Project. The work is on-schedule, so it is possible that 35th Ave NE will open before the end of the month of November.
Even after construction work is finished, there will be a lot to do — new trees and shrubbery will be planted along the banks of the creek and in the floodplain area.