Southwest Washington Regional Transportation Council

Bus on Shoulder Feasibility Study


As a response to growing congestion and in recognition of the need to develop multi-modal approaches to address it, regions throughout the U.S. have been looking for low-cost and innovative transportation solutions that can provide better transit options for commuters. The bus on shoulder (BOS) concept is one strategy that has been adopted in several states. First started in Minnesota 25 years ago, the concept has since been deployed in 11 states including California, Colorado, Delaware, Florida, Georgia, Illinois, Kansas, Maryland, New Jersey, Virginia, and recently in Washington in the Seattle area.

The bi-state region has a growing travel demand challenge crossing the Columbia River. Bus on shoulder is one of the strategies that the RTC studied to manage congestion. With no current major investments planned for the I-5 or I-205 Columbia River crossings, transportation agencies in the region are conducting several studies to identify strategies to improve the efficiency of the existing transportation system to move people across the river:

  • The Washington State Department of Transportation is leading a study to analyze the benefits and impacts of ramp metering on Clark County freeways.
  • RTC has funds programmed for an operations study that would look at ways to manage the region’s urban freeways more effectively that would incorporate results of the ramp metering study, and evaluate advanced traffic management, variable speeds, incident management, and other operational and high tech strategies.
  • The Oregon Department of Transportation has a project programmed for construction in 2018 to add northbound auxiliary lanes on I-205 between I-84 and Killingsworth.

Finally, the BOS Feasibility Study examined transit options that could offer improved mobility and efficiency for transit. The study conducted an evaluation on the application of BOS in the study corridors and identified a BOS pilot project for implementation.

The study area encompassed the I-205 corridor from the 18th Street interchange south through the I-84 interchange to Glisan Street and on SR-14 from I-205 to the 164th Avenue interchange.

SR-14 Pilot Project

In October 2017, C-TRAN and other regional partners launched a Bus On Shoulder pilot program that allows transit buses to use the shoulder of SR-14 between 164th Avenue and I-205 in Vancouver.

Final Report

The focus of the BOS Feasibility Study developed BOS concepts, evaluated potential geometric and operational constraints, identified opportunities for implementing BOS, and developed planning-level estimates of potential benefits to understand fatal flaws and overall feasibility of different BOS concepts and operating rules. The Study report documents the evaluation process and findings of the technical analysis, identities policy issues and includes a set of bus on shoulder recommendations for the corridors.

Bus on Shoulder Feasibility Study

Final Report Body, 4.39MB

Final Report Recommendations, 632KB