What have we done so far?
In 2015, we completed a 20-year capital improvement plan for our Willamette River Bridges. This plan placed a high priority on having a Burnside Street river crossing that can withstand a major earthquake.
In 2018, we completed a feasibility study for an earthquake-ready Burnside crossing. We looked at more than 100 river crossing alternatives on the Burnside lifeline route. With the help of community members and technical experts, we narrowed these down to four alternatives for further study in the Environmental Review phase.
On February 5th, 2021 a Draft Environmental Impact Statement was published documenting the findings of the environmental review. A 45-day public comment was provided through March 24nd, 2021. The comment period is now closed and the project team is reviewing community feedback. To access and view a library of the DEIS and related documents, visit the DEIS website.
How will the project be funded?
Funding the entire project will likely require local, state and federal funds. Multnomah County is funding its portion with revenue from the local vehicle registration fee.
How much will the project cost?
The recommended preferred alternative is estimated at approximately $825 million. The cost estimate will be refined as we get closer to design.
How will traffic be managed during construction?
In order to reduce the overall construction time by up to two years and save $90 million, the recommended traffic management approach is to fully close the bridge during construction and detour traffic to other bridges. The project team is considering different options for minimizing traffic impacts to the traveling public during construction. Construction is anticipated to begin in 2024.
Building a temporary bridge to maintain some level of traffic during construction was also considered. However, it was not recommended due to its high cost of $90 million, added construction time of up to two years and added impacts to natural resources.
Why is this project important?
Oregon is located in the Cascadia Subduction Zone, which puts us at risk of a major earthquake that will cause widespread damage to buildings, utilities, roads, bridges and the community. Experts say there is a 1 in 3 chance of a magnitude 8+ earthquake occurring within the next 50 years in our region. Portland’s aging downtown bridges are not expected to withstand a major earthquake. It could be weeks before any downtown bridge is usable after the earthquake. That’s why Multnomah County is taking the lead on making at least one downtown crossing earthquake ready.
Located in the heart of downtown, the Burnside Bridge is situated on a regionally established lifeline route across the Willamette River. After an earthquake or other disaster, a lifeline route allows first responders to get to where they’re needed and help distribute emergency supplies. In the event of a major earthquake, we will depend on the Burnside Bridge as the main emergency lifeline route across the Willamette River, connecting the city from east to west. A resilient Burnside Bridge will help our community recover after a major earthquake and provide a long-term river crossing that supports our transportation needs for the next century.
An earthquake-ready Burnside Bridge will:
- Provide an earthquake-ready Willamette River crossing
- Support post-earthquake emergency response
- Help the community and economy recover after a major earthquake
- Ensure long-term, multi-modal travel across the Willamette River
- Support our Regional Emergency Transportation Routes and seismic resiliency needs as stated in plans and policies
Metro designated Burnside Street, including the Burnside Bridge, as an emergency lifeline route in 1996. Stretching from Washington County to Gresham, the Burnside Street lifeline route has less risk of overpasses or structures collapsing along it during a large earthquake than other major roads, like I-84, I-5 and I-405. The Burnside lifeline needs an earthquake-ready river crossing to help reconnect friends and families; maintain access to fire stations, hospitals and other emergency services; and enable food, water, medical supplies and other necessities to be delivered where they are needed. It will be instrumental in helping our region recover.
It’s too expensive to upgrade all the bridges at the same time. The 2015 Willamette River Bridge Capital Improvement Plan assessment estimated the cost of making all of the County’s four downtown movable bridges earthquake resilient at between $2-3 billion. This cost does not consider improvements to ODOT’s Marquam and Fremont bridges that will be closed by a major earthquake. ODOT estimates it would take about four weeks after a major earthquake for emergency vehicles to access the Marquam Bridge, while the Fremont Bridge would not be usable after a major quake.
Over 100 options were studied during this project’s Feasibility Study phase, including tunnels, ferries, stacked bridges, couplet bridges, fixed bridges, floating bridges and other options. For more details about what was studied, check out the Feasibility Study Report.
Why is the Enhanced Seismic Retrofit not the Preferred Alternative?
The existing Burnside Bridge was built in 1926 before information about earthquakes was more readily available and understood. At that time, the Burnside Bridge was built with lightly reinforced rebar and supported on shallow timber piles embedded into quicksand-like soils. Given the age, location and materials of the Burnside Bridge, seismically retrofitting the bridge to withstand the size and magnitude of a major Cascadia Subduction Zone earthquake, and be immediately usable following such an event, makes this alternative more challenging than the replacement alternatives and greatly compromises the historic nature of the existing bridge.
Learn more about the reasons why the Enhanced Seismic Retrofit Alternative is being recommended as the Preferred Alternative here:
Oregon is subject to some of the world’s most powerful, recurring earthquakes. The last major quake in Oregon occurred 320 years ago, a timespan that exceeds 75% of the intervals between the major quakes to hit Oregon over the last 10,000 years. There is a significant risk that the next event will occur soon.
The United States Geological Survey has produced information about the distribution and severity of shaking from past subduction zone earthquakes around the world. That information shows that the Portland region will experience shaking levels strong enough and long enough to cause severe and widespread damage. A Cascadian Subduction Zone (CSZ) earthquake could cause strong shaking in Portland for four minutes. The next major CSZ earthquake is expected to devastate buildings, utilities, and transportation facilities. Learn more
The Burnside Bridge is over 90 years old and had a number of deficiencies that needed to be addressed in the near-term. The recent work made much needed repairs to cracked and crumbling concrete and the rusting steel framework that was compromising safety and operability of the bridge. The electrical and mechanical systems were also upgraded to keep the lift spans working. These targeted improvements were needed to keep the bridge operable and safe in the near term while we prepare for a major upgrade with the Earthquake Ready Burnside Bridge project. The improvements will not help the bridge survive a major earthquake.
It is estimated that a resilient crossing could be in place by the late 2020’s. The process includes performing the feasibility study (complete), an environmental study (in-progress), integrating public and stakeholder input (in-progress), developing the final design, and constructing the earthquake-ready crossing.
Multnomah County is the lead agency for this project. Advisory committees representing a range of community interests, agency partners and stakeholders provided input to the process of narrowing a comprehensive list of Willamette River crossing options to a shorter list of alternatives. They further evaluated the alternatives and considered community input in making a recommendation on a Preferred Alternative. The committees will also provide input during a more detailed evaluation before selecting a bridge type. There are many opportunities for public input on the study findings. In early 2021, the project will gather input on the bridge type and the Draft Environmental Impact Statement. In fall, 2021, the Board of County Commissioners and Federal Highway Administration will review all the input and recommendations before final approval and Record of Decision.
All members of the community are encouraged to participate. Community feedback will continue to influence key decisions leading to the approval of the preferred alternative and in selecting a bridge type. This website is the best way to stay informed and learn about opportunities to get involved, including signing up to receive project updates.
What can I do to be more prepared for a major earthquake event?
Experts say the best way to start is to develop an emergency plan for your family, friends and neighbors. Having a plan will improve the likelihood your family can communicate and reunite after a disaster. There are simple plans and tips to create an emergency kit at Ready.gov/kit.
How does this fit into other regional emergency plans?
The central location of the Burnside lifeline route and connections to other emergency routes means that an Earthquake Ready Burnside Bridge is central to the region’s ability to recover from a major Cascadia Subduction Zone earthquake. The Burnside Bridge is the only non-state owned Priority 1 Emergency Route across the Willamette River. ODOT is prioritizing the I-205 corridor as a statewide emergency lifeline route. Emergency managers are focused on helping our region prepare for an earthquake and other types of disasters. Learn more about our region’s emergency plans at PortlandOregon.gov/rdpo.