Washington State Patrol opened a southbound Interstate 5 diversion this afternoon, thanks to cooperation from Joint Base Lewis McChord, that should help address a major traffic problem from this morning’s fatal Amtrak train derailment that blocked all freeway lanes leading from Tacoma to Olympia and on toward Portland.

Here is an ongoing link to WSDOT and WSP detour information.

After the half-day total blockage of all lanes heading toward Olympia just south of Mounts Road, a couple miles south of the DuPont exit to Center Drive, sent motorists and truckers to the only semi-direct detour through Parkland-Spanaway and the Roy Y toward Yelm – a lengthy route significantly slowed by heavy volumes.

Beginning shortly after 12:30 p.m., military police and traffic controllers arranged a diversion off the I-5 freeway at Center Street, which is the primary entrance to Northwest Landing and the DuPont community. Traffic will flow through military property to meet up with State Route 510 and reconnect to the freeway corridor through Lacey.

Washington State Dept. of Transportation officials and WSP have not been able to predict when the major freeway corridor will re-open. Trooper Brooke Bova told media at mid-day that rescue and recovery workers had not yet been able to get inside of at least some of the Amtrak passenger cars, because they remain precariously suspended from a train bridge over the freeway.

Federal accident investigators are flying to the South Sound from Washington, D.C., to join Amtrak officials in beginning the investigation of what caused the day’s crash on the first official trip for the realigned passenger train service between Tacoma and points south.

Beyond the freeway interruptions, the derailment is likely to complicate passage of the standard heavy volume of rail cargo trains from Puget Sound ports to West Coast and central U.S. destinations. Not until National Transportation and Safety Board investigators release the scene and all emergency response is complete can heavy equipment begin to remove the smashed rail coaches and restore the interstate freeway right-of-way.

Sound Transit technically owns the trackage known as Point Defiance Bypass, which was recently significantly upgraded and rebuilt to host passenger train service.