Portland's I-5 Southbound Closes for Five Weeks of Earthquake-Proofing and Resurfacing

When a major highway requires structural repair, transportation departments typically schedule the work overnight or during weekend closures to minimize disruption. The Oregon Department of Transportation (ODOT) has taken a different approach for a critical stretch of Interstate 5 in Portland, shutting down the southbound lanes entirely for up to five weeks to complete a major seismic upgrade and resurfacing project.[1][5]

The closure, which began this week, affects the southbound lanes from the Interstate Bridge to the I-405 interchange. The primary objective is to replace the highway's expansion joints, which date back to the 1960s. These joints are designed to allow the concrete to expand and contract with temperature changes, but their age makes them vulnerable to failure during a major earthquake.[1][5]

By replacing the joints and resurfacing the roadway in a single, continuous operation, ODOT aims to complete the work more efficiently than a series of weekend closures would allow. "This is a critical safety upgrade for a corridor that carries a massive volume of freight and commuter traffic," an ODOT spokesperson noted in the project documentation. The agency estimates that the continuous closure will save months of intermittent disruptions.[1][5]

The immediate consequence, however, is the displacement of an estimated 40,000 vehicles per day. Southbound traffic is being diverted onto Interstate 405, a route that is already heavily congested during peak hours. The diversion is expected to cause significant delays, with ODOT warning drivers to expect their commutes to double or even triple in length.[1]

To mitigate the impact, the Portland Bureau of Transportation (PBOT) has launched a "Shift Your Trip" campaign, urging commuters to use alternative modes of transportation. The city is promoting its network of bike lanes, expanding transit service on key routes, and encouraging employers to allow remote work during the closure period. "We need everyone who can to avoid driving through the corridor," PBOT stated in its public outreach materials.[3]

The diversion of traffic has raised alarms among businesses in North and Northeast Portland, particularly those located along the primary detour routes. Local merchants fear that the anticipated gridlock will deter customers from visiting their establishments. "If people are stuck in traffic for an hour just to get across town, they're not going to stop for a coffee or a meal," one business owner told local media.[2][4]

The Pearl District Neighborhood Association has also expressed concern about the potential for increased traffic on local streets as drivers seek shortcuts around the congestion. The association is working with PBOT to monitor traffic patterns and implement traffic calming measures if necessary. The success of the closure strategy will depend heavily on the public's willingness to adapt their travel habits over the next five weeks.[3][4]

The project is part of a broader effort by ODOT to seismically retrofit critical infrastructure across the state. The Pacific Northwest is located in a seismically active region, and experts have long warned of the potential for a catastrophic earthquake along the Cascadia Subduction Zone. The I-5 upgrades are designed to ensure that the highway remains passable for emergency vehicles and relief supplies in the event of a major seismic event.[1][5]