Washington State's I-5 Fife Curve Identified as Major Traffic Bottleneck Due to Unique Factors
The 'Fife curve' section of Interstate 5 in Washington State is consistently identified as a significant traffic bottleneck, notorious for frequent backups. According to Yinhai Wang, a University of Washington civil engineering professor, three primary factors contribute to this congestion: heavy traffic volume, extensive merging and weaving due to numerous entrances and exits, and significant geometric changes in the roadway. The area sees a daily average of 206,000 vehicles, with numbers reaching 252,000 near the Tacoma Dome, making it one of the state's busiest sections. The presence of heavy semi-truck traffic, particularly to and from the Port of Tacoma, further complicates traffic flow as trucks' lane changes can disrupt vehicle movement. The concentration of interchanges for highways 18, 161, 167, 705, and 7 forces drivers to frequently merge and cut across multiple lanes. Additionally, the road's design, including exit-only lanes and angles, compels drivers to slow down, creating 'shockwaves' that ...