Northern portion of Gibbons Creek during the winter. The concrete flood wall is visible in the background.
The Steigerwald Reconnection Project is more than just a habitat restoration project. Realigning the Port of Camas-Washougal’s levee system is one of the primary project objectives. In order to reconnect Refuge lands and Gibbons Creek to the Columbia, we have to ensure nearby property owners like the Port’s Industrial Park will be protected from flooding at least as well as they were from the former levee system. All project elements and benefits flow from that realignment.
The realigned system’s west setback levee is oriented north-south and crosses State Route (SR) 14 just west of the Gibbons Creek bridge. It is composed of an earthen levee to the south of SR 14 and a concrete flood wall to the north. SR 14 passes through a gap in the levee that is 73-feet wide and 8-feet tall. During large flood events, the Port, who owns and operates the levee, will close this gap in the levee by detouring traffic around the site (north/south on 32nd Street and east/west on Old Evergreen Highway) and installing a concrete closure structure.
Vertical support beams placed across SR14 during the test installation of the flood wall.
The closure structure will only be installed when Columbia River flood levels approach the 500-year flood stage, which is several feet higher than the peak of the 1996 flood. So we anticipate that the closure structure will be installed very infrequently. However, the project team must ensure it works, and the Port must be prepared to install it during an emergency flood-fighting scenario.
The concrete wall sections are lowered into place between the vertical support beams.
So at 9pm on August 4, we performed the first test installation. The project team closed this portion of SR 14 and detoured traffic, while the project’s prime contractor, Rotschy Inc., successfully installed the structure with Port staff there to observe and be trained on the process. To ensure they are prepared in the future, the Port will inventory the concrete panels and support beams annually and perform a complete trial installation every five years.
The completed flood wall in place across SR14 during the first test installation.