Temporary Tunnel Closure

posted Jun 27, 2011, 3:16 PM by Town Clerk   [ updated Jun 27, 2011, 3:33 PM by Rob White ]

On June 17th the town conducted an inspection of the tunnel at the request of Pt Ruston. There is a large crack on the west end of the bridge that appeared to Pt Ruston personnel to be growing. Here is our town engineers report on the inspection:

The structural condition of the tunnel has not changed since the last inspection provided by Pierce County in the later part of 2007.

In my opinion, there are no concerns of imminent catastrophic failure.

Naturally, the tunnel will need periodic inspections and observations with time.

The inspection was conducted this morning with a traffic shutdown from 9 am until 10:15 am.  Assisting me with the inspection was Kraig Shaner, P.E. from the Pierce Co. Public Works Department (who provided the previous tunnel inspections, including the last formal inspection in the later part of 2007) and Jim Parvey, P.E. City Engineer for Tacoma.

Mr. Shaner provided follow-up readings on the existing strain gauges that were deployed years ago.  The readings indicated that there were no changes in the strain gauges in five of the six locations, and a very minor change in one location.

We have relayed the results to Pt Ruston and provided them with our opinion on the situation. Had this crack been growing the town would have closed the tunnel immediately. The tunnel is still slated for permanent closure sometime in early July.