neighbors4a-bettercrossing.org
NEIGHBORS FOR A BETTER CROSSING IS AN OREGON NON-PROFIT
ALTERNATIVE DESIGN
THE INTERSTATE BRIDGE REPLACEMENT (IBR) SALES TEAM MISLED US!
Not only has the IBR failed to provided full disclosure about its “Bridge Replacement” designs, in briefings to our elected officials the IBR team headed by Greg Johnson calls the tunnel option a “Myth,” which is refuted by the IBR’s own Tunnel Concept Assessment Rev 2!
THE GRAND OLD LADY CAN BE SAVED & REPURPOSED!
Interstate bridge History: https://www.hayden-island.com/stop1/
WITH I-5 TRAFFIC CHANNELD THROUGH AN IMMERSED TUBE TUNNEL, THE CURRENT HISTORIC BRIDGE CAN BE PRESERVED AS AN ATTRACTIVE GATEWAY BETWEEN WASHINGTON & OREGON!
HOW AN IMMERSED TUBE TUNNEL (ITT) IS CONSTRUCTED
Immersed tunnels are widely used throughout the world. A trench is first dug in the riverbed, then prefabricated tunnel segments are lowered into position and connected to adjacent segments. The tunnel is then backfilled & covered with riverbed to a specified depth. An ITT can accommodate multiple lanes of traffic, light rail, bus lanes, and bike & pedestrian paths.
Our I-5 Bridge is subject to a major Cascadia Seduction Zone earthquake, and is located in a “Soil Liquefaction Area.”
Scientists predict there is a 37% chance that a mega-thrust earthquake in this fault zone will occur in the next 50 years.
An Immersed Tunnel is far more resilient to earthquakes than a bridge, and will accommodate everything a bridge can, including light rail!
Here’s a short YouTube Video about the installation:
Note: Whether by intent or not, the Interstate Bridge Replacement (IBR) Sales Team misled us.
In briefings with elected officials, the IBR team called the tunnel option a “Myth,” stating a network of access roads were needed to connect the tunnel with I-5 & SR-14 in Vancouver, but that conflicts with the IBR’s Tunnel Concept Assessment Rev 2, Pg 18, Para 3.4 by WA Professional Engineer Robert Turton, that states a tunnel will connect to above ground network (I-5 & SR-14) with cut-and-cover connections at either end.
If an immersed tunnel concept was selected for an similar application in Vancouver BC, why not here?
A WSDOT Video on the advantages of a tunnel instead of a bridge in an earthquake:
