A sound wall on the Woodrow Wilson Replacement Bridge will now be a reality. That was the word from the Federal Highway Administration in a letter to the Virginia Department of Transportation this week.
"This is a real win/win for Alexandria and everyone concerned with the Woodrow Wilson Bridge Project," said John R. Undeland, project Public Affairs director. "The approved wall looks good aesthetically, does the job, and is also very safe."
FHWA's blessing was the final hurdle in a long struggle to get a sound wall installed on the new replacement bridge that will significantly lower the decibels in the Yates Gardens area of Old Town Alexandria. It was sought by the city, area residents, and project personnel.
The primary stumbling block had been opposition from the National Capital Planning Commission and the U.S. Commission of Fine Arts. Their objections were based on the opinion, "It would detract from the aesthetics of the "signature" bridge that has been approved through a public process" as well as create a tunnel effect and challenge the safety of pedestrians and bicyclists on the bridge.
What finally won the day was the design of the wall. Instead of being a solid opaque structure it will be constructed of "a transparent material called Paraglas." It is one and one-half inches thick and eight feet in height. It is an acrylic product that is UV stabilized to eliminate yellowing.
As a distortion-free, transparent material, it does not obstruct the view to the north which was a paramount concern to the Commission. Bridge engineers came up with the design based on examples in use throughout Europe.
IN THOSE USES, the material has been verified to reduce the decibel count ranging from a minimum of four to a maximum of eight. That meets the goal of the bridge project of reducing the noise level based on projected 2020 traffic volumes.
The wall will extend from the abutment at South Royal Street out approximately 1,600 feet to the former location of the old Seaport Foundation building. There will also be a barrier on the south side of the new highway as it rises to the bridge but it will not extend onto the actual bridge, Undeland explained.
Construction of the sound wall will be one of the last phases of the project since it will be placed on the bridge that will replace the existing Woodrow Wilson Bridge. Work on it will not commence under the new south bridge is fully operational.