Description: Off-peak traffic volumes in the Puget Sound region of Washington State are increasing, and public concern about congestion during non-commute periods has caused WSDOT to re-examine the current policy of restricting HOV lanes to transit vehicles and carpools 24 hours per day, 7 days per week. In many parts of the country, HOV lanes are open to general traffic during non-peak hours. Should WSDOT adopt this less restrictive lane use policy?

This report examines the tradeoffs that a change in off-peak HOV lane usage would involve. The basic issues that are examined include the following: 

• What congestion relief benefits would result?
• Would these changes have adverse impacts on HOV formation and/or HOV lane compliance rates?
• Would the off-peak use of HOV lanes by general purpose vehicles create safety concerns?
• Would highway and transit operational problems be created?
• What would be the monetary impacts of changing off-peak HOV lane usage?

Supported by a variety of performance graphics and statistics, the report concludes that no improvement in mobility would be obtained by relaxing the current Puget Sound HOV lane operating restrictions to allow off-peak use of the HOV lanes by general purpose traffic.

• Date Published: June, 2000
• Publication Number: WA-RD 488.2
• Last Modified: May 15, 2007
• Authors: Mark E. Hallenbeck, John M. Ishimaru, Jennifer Nee.
• Originator: Washington State Transportation Center (TRAC)
• # of Pages: 28 p., 323 KB (PDF)
• Subject: Compliance, Economic impacts, Freeways, High occupancy vehicle lanes, Impacts, Mobility, Off peak periods, Policy, Traffic congestion, Traffic volume, Traffic safety.
• Keywords: HOV, HOV performance, freeway performance reporting, off-peak traffic, Puget Sound Region.
• Related Publications: Weekend Freeway Performance and the Use of HOV Lanes on Weekends, (WA-RD 488.1).

This abstract was last modified April 29, 2008