Boone Bridge (Oregon)

The Boone Bridge is a pair of parallel girder bridges that carry Interstate 5 (I-5) over the Willamette River between Wilsonville and Newberg, Oregon. Officially named the Boone Bridge, though often referred to in the plural, it constitutes a significant traffic bottleneck in the Portland metropolitan area due to its age, design, and the high volume of traffic it carries.

The bridge is named for Alphonso Boone, the grandson of Daniel Boone, who settled in the area near present-day Wilsonville in the 1840s.

The original bridge was completed in 1954, carrying two lanes of traffic in each direction. A parallel bridge was constructed and opened in 1970 to accommodate increasing traffic volume. The two bridges each now carry three lanes of traffic, and have no emergency shoulder.

Frequent traffic congestion on the Boone Bridge has led to numerous studies and proposed solutions to alleviate the bottleneck, including widening the bridge, adding auxiliary lanes, and exploring alternative transportation options. The Oregon Department of Transportation (ODOT) has undertaken various projects over the years to improve traffic flow, including ramp metering and variable speed limits. As of 2024, the Boone Bridge remains a major transportation challenge in the region.