WSDOT Responds to Expert Review Panel Recommendations
On September 20, 2006 WSDOT released the results of preliminary revisions to cost estimates for the SR 520 Bridge Replacement and HOV Project and the Alaskan Way Viaduct and Seawall Replacement Project. The release of this information follows suggestions recently made by the Expert Review Panel, and addresses the likely impact of recent worldwide construction cost inflation on project costs.
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New Cost Estimates
“It is important that new estimates be in the public’s hands,” said Doug MacDonald, Secretary of Transportation. “Sharply higher prices for construction materials in recent months have been seen in projects across the country and even around the world. The entire construction industry has been affected by these trends. These two important projects will be no exception, and we have agreed with the Expert Review Panel that the best information we have now should be made available to everyone.”
Final stages of the cost estimate updates were conducted under the eye of several Expert Review Panel members in Seattle over recent weeks. Lee Baker, P.E., a construction cost specialist and member of the Expert Review Panel, said: “Today, new cost numbers are not welcome news on any project, but we support the approach WSDOT has taken and it follows our recommendations. We believe the cost ranges that WSDOT has prepared are representative of what the currently envisioned projects will cost. Use of specific costs at this preliminary stage are sufficient for comparing and selecting the alternatives to be built, and even more work will be required for predicting final costs.”
A team of in-house WSDOT experts and private sector consulting engineers working under the supervision of David L. Dye, WSDOT’s Urban Corridors Office Administrator, prepared the new estimates. “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. Our project design and construction efforts will, we hope, stay very close to the ‘likely range’ estimates,” Dye said.
Alaskan Way Viaduct and Seawall Replacement Project
Core Tunnel:
|
Re-evaluated Most Likely Cost, Sept 2006 |
Previous Cost Range, Oct/Nov 2005 |
|
$4.63 billion |
$2.98 - $3.63 billion |
Core Elevated Structure:
|
Re-evaluated Most Likely Cost, Sept 2006 |
Previous Cost Range, Oct/Nov 2005 |
|
$2.82 billion |
$1.99 - $2.36 billion |
SR 520 Bridge Replacement and HOV Project
4-Lane Alternative:
|
Re-evaluated Most Likely Cost, Sept 2006 |
Previous Cost Range, April 2005 (Pre-Katrina) |
|
$2.79 billion |
$1.67 - $2.02 billion |
6-Lane Alternative with Montlake Interchange:
|
Re-evaluated Most Likely Cost, Sept 2006 |
Previous Cost Range, April 2005 (Pre-Katrina) |
|
$3.90 billion |
$2.33 - $2.83 billion |
6-Lane Alternative with Pacific Interchange:
|
Re-evaluated Most Likely Cost, Sept 2006 |
Previous Cost Range, April 2005 (Pre-Katrina) |
|
$4.38 billion |
$2.73 - $3.10 billion |
The Alaskan Way Viaduct and Seawall Replacement Project
The viaduct and Alaskan Way surface street together carry more than 120,000 vehicles each day (about one quarter of all north-south traffic through Seattle) and serve as an important route for commuters and freight. The seawall, which is included in these new project estimates, supports Alaskan Way and the soil underneath the viaduct. Immediately after the 2001 Nisqually earthquake, WSDOT made $3.5 million in earthquake repairs to keep the viaduct safe and functional and began semi-annual earthquake inspections to closely monitor cracks, structural movement and foundation integrity.
The SR 520 Bridge Replacement and HOV Project
The 42-year-old SR 520 Evergreen Point Bridge is 1.5 miles long and carries approximately 115,000 vehicles daily. The bridge approaches, which run between Portage Bay and Lake Washington, are vulnerable to earthquakes, and the floating bridge is vulnerable to windstorms. In February 2006 the 520 bridge had to be closed to traffic during an evening rush-hour winter storm, causing hours of massive traffic congestion on I-5, I-405, I-90 and other roadways around the region.