Scary, but necessary: Planning for the Big One
Nothing causes more nightmares around ODOT than planning for the Big Earthquake. When it hits, it would create an unparalleled catastrophe, the physical, economic and human recovery lasting for years — and it would be much worse if we're not prepared.
Everyone in Oregon must be aware of this threat by now. A Cascadia Subduction Zone quake could hit all of Western Oregon at once, the Coast to the Valley, as it has through history. Potentially, it could cripple the statewide transportation network in a matter of a few minutes. Bridges would collapse, highways would fail and thousands may die if the transportation system cannot bring the services and supplies for the recovery where it's needed.
Such an earthquake would change the face of Oregon. The Oregon Coast and the Willamette Valley would get hurt the worst. And that means Eastern Oregon and our neighboring states would provide most of the help. Most of U.S. 101 and those wonderful old bridges may be impassable from lengthy ground-shaking. Those bridges just weren't made to withstand the stresses that may come in an earthquake.
In addition to the vital role the transportation system would play in rescue and recovery efforts, Oregon's transportation infrastructure serves as the state's economic backbone. Strengthening key highway corridors before a major earthquake could not only help ease economic losses after but would assure a stronger system even if the earthquake takes place many years in the future.
ODOT's responsibility is clear. In the years since the enormity of our seismic threat became clear, ODOT has been taking steps to strengthen the transportation lifelines. The more we can do to keep the system from failing, the smoother our initial response to the disaster and long-term recovery.
We are working to seismically replace or retrofit the vulnerable bridges and address unstable slopes on key lifeline routes to better allow for rescue and recovery. Today, seismic strengthening is part of many major highway projects we take on.
Some you may have heard of, like the project to improve Interstate 205 in and around the Abernethy Bridge, which carries I-205 over the Willamette River in Clackamas County. The bridge underwent seismic strengthening more than a decade ago, but more is needed. With the bridge improvements we plan in this project, we can be confident that the Abernethy Bridge would continue to function soon after a big earthquake. Numerous other bridges along this I-205 corridor need seismic strengthening as well, crossings over creeks and roads. What it all adds up to end the end is a seismically stable corridor that can help move the goods and medical supplies we would need.
ODOT has laid out a network of critical routes that we are working to strengthen, including US 97 from California to Washington, the I-5 and I-205 corridors through the state, and important connections across the Cascades and to the Coast. We're also working with local governments on specific needs within their communities and to develop plans to use local roads when state highways fail. Choosing the lifeline routes involves many variables including access to fire stations, hospitals, ports, airports, railroads, maintenance facilities, emergency response staging areas and utilities.
Redmond Airport would be used as the main hub for providing goods and medical supplies. Therefore, creating a resilient highway system that would provide freight movement into Redmond and across the Cascades to impacted communities becomes an important place to start for our program. Because the first phase would serve as the cornerstone of the entire program, a smart corridor selection becomes critical for the success of this program. Starting the program with retrofitting less vulnerable segments to get this backbone for response in place is the most economical approach with the highest return on investment.
The Oregon Transportation Commission and the Legislature have already begun making investments in these lifeline routes by repairing and replacing bridges and fixing slopes that would fail in an earthquake. In some cases, such as I-5 between the Willamette Valley and the Rogue Valley, we are taking a triage approach, creating a passable route even though we can't address all the needs on the interstate.
But creating a resilient highway system won't be a task that we finish soon; given the multibillion dollar price tag, it will require decades to complete, and it would require additional investments.
Geologists tell us the question isn't really if but when this will happen. Planning for the Big One is now part of the psyche of every Oregonian and it's our job at ODOT to plan for the worst.
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