The Seattle Department of Transportation bridge crew partnered with Seattle Public Utilities (SPU) to replace an old pedestrian bridge that crosses Thornton Creek near Sacajawea Elementary school. SPU’s project to improve Thornton Creek habitat and storm flows increased the creek flood plain to approximately seventy feet. The new conditions required a replacement of the popular pedestrian crossing at 20th Avenue Northeast between Northeast 100th Street and Northeast 98th Street.
The Thornton Creek Bridge is a pedestrian route used by neighbors and Sacajawea Elementary students. SDOT and SPU wanted to replace the old ten-foot bridge with a structure that would not damage the sensitive creek environment and that would improve the safety of this school route for Sacajawea, located two blocks south from the new bridge.
An innovative composite bridge was selected. This is the first bridge of this type owned by SDOT. The bridge was preassembled at the manufacturer to make sure all the components fit correctly. Its modular components provided for rapid construction at the site. The entire bridge was constructed in four days, just in time to accommodate students who walk to Sacajawea Elementary.
Seattle Public Utilities and SDOT will provide safety precautions for students during the time that children are walking to school. Fenced walkways on both ends of the bridge will keep students away from construction work. A flagger will stand at each end of the bridge to alert crews when students are present and guide students safely through the pedestrian path. Also, large equipment will pause when students are present.
The bridge will be open only during times children will be walking to and from school, from 8 to 9 a.m. and from 2:45 to 3:30 p.m. on weekdays, and is scheduled to reopen to all pedestrians when construction is complete at the end of October.