Southwest Washington Regional Transportation Council

2015 Congestion Monitoring Report

Roadway congestion is a primary concern facing the users of the Clark County (Washington) transportation system as it adversely impacts quality of life and economic development. In order to evaluate current roadway conditions, assess regional transportation needs, and outline strategies to manage current and future roadway congestion, RTC recently completed its Congestion Management Process: 2015 Monitoring Report.

As the federally designated Metropolitan Planning Organization for the Clark County region, RTC is required by federal law to maintain a Congestion Management Process. The CMP is an on-going systematic process for managing congestion that provides information and analysis on multimodal transportation system performance and on transportation strategies to alleviate congestion and enhance mobility. The CMP is a vital element of the RTC planning process and is used as a guide to develop project recommendations for the Transportation Improvement Program and the Regional Transportation Plan.

The CMP takes a region-wide approach to identify and address congestion concerns, and develops a “toolbox” of strategies to address the most congested corridors. The 2015 Monitoring Report and its findings were endorsed by the RTC Board at its July meeting. Copies of the full report, summary report and supporting data are now available on RTC website at

Key Findings

With recent population and employment growth, region-wide traffic congestion has been on the rise for the past five years. This has resulted in an increase in both morning and evening peak hour delay, especially on bi-state facilities.

Overall, the 2015 Monitoring Report shows that the implementation of the RTP can address most of the corridor capacity needs over the next 20 years. This does not mean that congestion will not exist, but through the implementation of additional operational improvements and by addressing localized bottlenecks the region can better manage congestion.

The lack of transportation revenues and regional consensus for the I-5 Bridge replacement, along with other key corridors, is contributing to worsening traffic conditions. Lack of progress on select projects will result in delay in achieving the project benefits and add to future project costs.

Key Needs

The CMP and RTP identify the need for the following key solutions to address congestion within Clark County.

In the RTP and Funded:
  • I-5/Mill Plain Interchange (2026 Construction)
  • SR-502 Widening (Under Construction)
  • NE 18th Street Widening, 112th to 164th Avenue
    • Partial funding only: 18th St, Four Season to 136th Avenue (2017 Construction)
  • Padden Parkway Intersection Improvements
    • Partial funding only: Padden/94th Avenue Intersection (Under Construction)
In the RTP but Not Funded:
  • I-5 Interstate Bridge and interchanges
  • I-5/I-205/SR-500/SR-503 Corridor Operational Improvements
  • I-205, SR-500 to Padden Widening
  • I-205/SR-14 Interchange
  • SR-14, I-205 to 164th Avenue Widening
  • SR-500/42nd & 54th Avenues Grade Separation
  • Fourth Plain, 117th to 164th Avenues Operational Improvements
  • Mill Plain, I-205 to 192nd Avenue Operational Improvements
  • NE 112th Avenue, 49th Street to SR-500 Operational Improvements
  • Bi-State Transit Expansion/Operational Improvements
  • Other Select Intersection Improvements
  • Other Select Operational/Capacity Improvements

July 10, 2016 ⋅ PermaLinkArchive