East Link's I-90 Bridge "Surprises"

An earlier post opined the results of Sound Transit’s closure of the South Bellevue P&R in November will be an unwelcome “surprise” for anyone who uses an east side P&R for access to transit.   I suspect far more commuters will be “surprised” when Sound Transit closes the I-90 Bridge center roadway next year to begin their 6-year plan to install light rail tracks there.  (At least many if not most of those I’ve talked to weren’t aware of the closure.)   

The only reason Sound Transit will be allowed to close the center roadway is the WSDOT lawyers told a federal judge in the Freeman case the R-8A configuration, which added the 4^th lanes to the bridge outer roadway, didn’t need the center roadway for vehicles.  Yet, the very document the WSDOT cited “I-90 Twp-Way Transit and HOV Operations Project, Record of Decision, Sept 2004", included the following:

Alternative R-8A will provide HOV lanes on the outer roadways.  It will retain both lanes on the center roadway

Sound Transit’s decision to ask voters to approve ST3 prior to the bridge closure “might” reflect concern the “possible” congestion would result in many commuters voting to reject it.  (Its also the “possible” reason they delayed closing the South Bellevue P&R, initially scheduled for March, until after the vote.)

Sound Transit has ample reason to be “concerned”.   The congestion on I-5 HOV lanes is a clear indication that a single lane cannot accommodate both non-transit and transit HOV traffic.   One would reasonably expect the WSDOT would feel compelled to demonstrate their claim to the judge that the center roadway was not needed for vehicles. 

They could do so by temporarily closing the center roadway once they added the HOV lanes to the bridge outer roadways.  Yet WSDOT has no plans to force Sound Transit to do so.  I’ll leave it to others to decide whether the potential for increased SR520 toll revenue from those avoiding the resultant I-90 congestion influenced their decision. 

The other potential “surprise” is the fact that Sound Transit may still not have an acceptable bridge design.  East Link is the first attempt to install light rail on a floating bridge.   Last August Sound Transit signed a $20 million contract to complete the design they’d already spent $38 million on earlier.  The Aug 16^th Seattle Times article about the new contract quoted a WSDOT official telling the board:

“We have not indentified any fatal flaws that would prevent light rail from being installed on this corridor”

Yet nine months later the March 24^th Sound Transit board minutes included the following regarding the East Link extension:

“In the I-90 corridor the system design is at 90% and civil design is advancing to 90%.  The independent review team (IRT) identified 23 issues as part of the preliminary engineering. Twenty-two issues have been closed and the staff is working to close the final issue.” 

The fact that nearly 9 months after signing the contract they still apparently hadn’t completed the design suggests the flaws if not “fatal” are surely “serious”.  None of the subsequent monthly board agendas includes any update of the bridge design status.  Failure to do so could be the “ultimate” surprise.   Knowing Sound Transit, if they do fail to come up with an acceptable design they'll wait until after the vote this fall to admit the problem.