Southbound I-5 Boone Bridge Congestion Study

Wilsonville and ODOT to Study I-5 Congestion Solutions South of Wilsonville 

Aerial-Image-SB-I-5-Boone-Bridge-Congestion-Study-South-Oblique-web3The study is one component of several projects that the City is undertaking to reduce morning and evening commute-hours traffic congestion in the I-5/Wilsonville Road interchange area. 

Additionally, the planning effort is part of the larger City Council-directed push for a more comprehensive “South Metro I-5 Corridor Study” that would examine the costs and benefits of both a range of potential highway improvements to I-5 from Tigard/Highway 217 to Aurora/Donald Ehlen Road Exit 278, along with increased public-transit options.

After the Council approved a $50,000 City contribution to the study, the planning process started in October 2017 and concludes in the summer of 2018. The three phases of work include: 

  • Technical analysis of benefits and impacts; 
  • Gathering of public input and preferences; and, 
  • A resolution of support by the City Council, then adoption by the Oregon Transportation Commission for inclusion in the updated Metro Regional Transportation Plan. 
During legislative hearings on the successful “Transportation Investment Package” (House Bill 2017) passed in 2017, a Congestion & Freight Mobility Workgroup estimated that the “Boone Bridge & Lanes” project would cost $120 million and could be constructed in 10-15 years. The City and ODOT seek to accelerate potential consideration of the project by obtaining a more accurate cost estimate and traffic-mitigation impact of potential improvements. 

Traffic Issues with the Southbound I-5 Boone Bridge Area 

The mile-plus stretch of southbound I-5 from Wilsonville Road Exit 283 past Miley Road Exit 282B to Highway 551 Exit 282A has a number of problems.

Symptoms of the Problem

  • Traffic bottleneck between I-5 Wilsonville Road interchange (Exit 283) and two nearby interchanges at Miley Road (Charbonneau Exit 282B) and Wilsonville-Hubbard Cut-off Highway 551 (Exit 282A).
  • Up to 4.5 hours of daily congestion.
  • Evening commute speeds drop to 25 mph, with the PM queue backing-up to I-205.
  • I-5 congestion causes spill back on Wilsonville Road and nearby intersections at Boones Ferry Road and Town Center Loop West.
Contributing Factors

  • Over 129,000 vehicles per day pass-by Wilsonville on I-5, with 62,000 vehicles crossing the Boone Bridge going south. For comparison, the I-5 Boone Bridge carries nearly as much traffic as the I-5 “Columbia River Crossing” Interstate Bridge—only four percent less traffic—and one-third more semi-trucks.
  • Extensive traffic weaving between lanes that induces slow-downs and accidents: More than 20% of the evening peak-hours traffic enters I-5 at Wilsonville Road on-ramp while over 35% of the traffic exits at Charbonneau or Wilsonville-Hubbard Cut-off Highway 551 that also accesses Canby. Over the four-year period of 2011-15, this stretch of I-5 had 148 automobile accidents.

City Council Approves Agreements with ODOT for I-5/Wilsonville Road Interchange, Boone Bridge Study, and More Traffic Mitigation Plans

In October 2017, the City Council approved an agreement with the Oregon Dept. of Transportation (ODOT) for a construction project to modify the I-5/Wilsonville Road interchange Exit 283 southbound freeway on-ramp. The $700,000 project adds a third stacking lane to the metered I-5 on-ramp in order to increase capacity to hold an additional 25 vehicles waiting to enter the freeway during evening rush-hour.
The project is part of five congestion-improvement projects approved by the City Council totaling an approximately $1 million in the I-5/Wilsonville Road/Boones Ferry Road intersection area designed to improve traffic flow and reduce congestion. 

Other congestion-relief projects include:

  1. Lengthening the southbound Boones Ferry Road double left-turn lanes onto eastbound Wilsonville Road, which is complete.
  2. Reconstructing the southern, signalized entrance/exit to Old Town Square/Fred Meyer shopping center to include a second travel lane on northbound Boones Ferry Road between the exit/entrance and Wilsonville Road. 
  3. Signing “No Turn on Red” during evening rush-hour for right-turn movements from northbound Boones Ferry Road onto eastbound Wilsonville Road.
  4. Working with ODOT on the Southbound I-5 Boone Bridge Auxiliary Lane Study; see page 1 for details.
  5. Considering installing ‘red-light’ cameras to deter running red lights and blocking intersections.