The Washington State Department of Transportation has revised its cost
estimates for two major construction projects.
The latest cost estimates are not surprising – engineering and
construction costs are going up on the proposed Alaskan Way Viaduct and seawall
replacement project in Seattle and the State Route 520 Bridge replacement
project over Washington Lake that includes high-occupancy-vehicle lanes.
In an announcement Wednesday, WSDOT estimated a re-evaluated cost of
$4.63 billion on the Alaskan Way Viaduct tunnel and $2.82 billion on Viaduct
elevated structures, up from $3.63 billion and $2.36 billion, respectively.
On the SR 520 Bridge and HOV lanes, the estimates rose from $2.02
billion to $2.79 billion on the four-lane alternative; $2.83 billion to $3.9
billion on the six-lane alternative to include the Montlake Interchange; and
$3.1 billion to $4.38 billion on the six-lane alternative to include the
Proofing for earthquakes adds to the cost estimates, WSDOT officials
Construction is slated to begin in 2010.
“These estimates introduce a new number, the ‘likely cost,’ as our best
way of giving the public good project comparisons when tomorrow’s inflation
rates are hard to guess and ‘worst case’ ranges are more pessimistic than the
future we actually expect to encounter,” David L. Dye, Urban Corridors Office
administrator with the Washington State Department of Transportation, stated in
a press release.
“Our project design and construction efforts will, we hope, stay very
close to the ‘likely range’ estimates.”