Bob Ortblad says the IBR fraudulently disqualified an immersed tunnel alternative that would require no drilled shafts and could save hundreds of millions of dollars
Editor’s note: Opinions expressed in this letter to the editor are those of the author alone and may not reflect the editorial position of ClarkCountyToday.com
A comparison of the design and contract costs for the SR 520 Portage Bay Bridge reveals that the estimated cost for the current I-5 Bridge design in the Interstate Bridge Replacement Program (IBR), which ranges from $1 billion to $1.5 billion, should be increased by approximately 50%.
The SR 520 Portage Bay Bridge and Lid project was bid in November 2023 at $1.375 billion, which is 70% above the engineers’ estimate. Skanska, the design-build contractor, attributes about 80% of this cost — approximately $1.1 billion — to the new bridge itself. Notably, the Portage Bay Bridge is nearly the same length as the proposed I-5 Bridge design and is supported by identical 10-foot-diameter drilled shafts. Furthermore, this bridge is being constructed in a shallow, weather-protected cove that is only 10 feet deep.
In contrast, the design for the I-5 Bridge is larger and situated in a more challenging location. The I-5 Bridge is approximately twice as wide, featuring bridge spans of 500 feet that are 200 feet longer and nearly four times heavier than those of the Portage Bay Bridge. Its piers must be 80 feet higher, and its 250-foot drilled shafts are 100 feet longer. Additionally, these shafts are likely to encounter cobbles and boulders in the Columbia River’s riverbed, which is deeper and affected by tides, currents, and strong winds.
WSDOT bid documents for the Portage Bay Bridge initially indicated 106 drilled shafts. However, Skanska, the design-build contractor, increased this number to 130. In contrast, the current design for the I-5 Bridge includes only 96 drilled shafts, despite being twice as large and heavy. This discrepancy raises a critical question that WSDOT and the I-5 Bridge team need to address: why does the I-5 Bridge design have significantly fewer drilled shafts compared to the Portage Bay Bridge?
The IBR fraudulently disqualified an immersed tunnel alternative that would require no drilled shafts and could save hundreds of millions of dollars.
Bob Ortblad MSCE, MBA
Seattle
Also read:
- Opinion: The many reminders not to speed
Doug Dahl examines the many technological and policy-based reminders aimed at reducing speeding and explains why most drivers still choose not to use them voluntarily. - Rep. John Ley’s new bill calls for an independent audit of Interstate 5 Bridge Replacement Project
Rep. John Ley introduced legislation requiring an independent audit of the Interstate 5 Bridge Replacement Project to review costs, management, and oversight. - Opinion: IBR’s evasive, misleading and dishonest excuses for higher cost
Joe Cortright argues the Interstate Bridge Replacement Program has withheld detailed cost estimates while offering contradictory explanations for rising costs tied to the I-5 Bridge project. - Rep. David Stuebe sponsors bill to strengthen enforcement of auto insurance laws and protect Washington drivers
Rep. David Stuebe has introduced HB 2308, a bill aimed at strengthening enforcement of Washington’s auto insurance laws and increasing accountability for repeat uninsured drivers. - Letter: Interstate Bridge Replacement’s Park & Ride insanity
Bob Ortblad criticizes the Interstate Bridge Replacement Program’s proposed Park & Ride garages, arguing the costs are excessive and unlikely to receive federal funding.
The benefits and costs of a tunnel should be considered and weighed against a bridge option. A Tunnel could
** Save $100’s of Millions of dollars
** Save the views from the rivers edge and maximize sunshine, not put VAncouver under the dark shadow of a larger, taller bridge
***Save Construction Time
***Save Salmon with less disturbance of the riverbed
Improve Seismic resilience
see also https://www.clarkcountytoday.com/opinion/letter-ibrs-billion-dollar-risk-another-abernethy-bridge-financial-disaster/
“Similar to a floating bridge, an immersed tunnel is supported by displacing its weight, according to Archimedes’ principle. This design is faster to build, could potentially save $1 billion associated with drilled shafts, and would also be more earthquake-resilient than a foundation based on drilled shafts.”
Why are we still talking about the light rail on this project? The people clearly don’t want it!