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HOV Improvements on Signalized Arterials in the Seattle Area. Volume III, N.E. 85th HOV Study


This paper will discuss the problems that are inherent with adding a higher speed HOV lane to an arterial with its unlimited access points. Investigation of current literature will show that although freeway HOV applications have been researched and understood to an adequate degree, almost no data of any kind is available to predict the effectiveness of an arterial HOV project. Further, it will be proposed that not only does the research not exist, but that the "measures of effectiveness" to evaluate existing arterial HOV lanes are severely lacking.

In addition to the literature search, a motorist survey was handed out to collect data describing commute trip behavior. Questions about trip origin, destination, and purpose were asked to determine what residential and commercial zones were being served by NE 85th/Redmond Way, and for what purpose. The questionnaire also requested information on the duration of the trip and the occupancy of the vehicle. This data was used as input for a mathematical model to predict the volumes on the facility one year after the implementation of an HOV lane. Since the model was based on past freeway applications across the nation, the threats to validity which that causes were also presented. The final questions on the survey concerned the motorists' own prediction about how likely they were to carpool and what they thought were some of the problems preventing them. These views were compared with the results from the model. The predictions and resulting effectiveness of the project were evaluated versus the stated objectives of the Eastside Transportation Program (ETP) policy statement.

  • Date Published: February, 1993
  • Publication Number: WA-RD 301.3
  • Last Modified: October 17, 2007
  • Authors: Nancy L. Nihan, Lester O. Rubstello.
  • Originator: Washington State Transportation Center (TRAC)
  • # of Pages: 104 p., 2,672 KB (PDF)
  • Subject: Alternatives analysis, Arterial highways, Carpools, Data collection, Forecasting, Guides to the literature, High occupancy vehicle lanes, Information organization, Literature reviews, Mathematical models, Measures of effectiveness, Metropolitan areas, Origin and destination, Questionnaires, Streets, Surveys, Traffic volume, Travel behavior, Trip length, Trip purpose, Vehicle occupancy.
  • Keywords: Arterial HOV, HOV, high occupancy vehicle, Seattle (Wash.)
  • Related Publications: HOV Improvements on Signalized Arterials in the Seattle Area. Volume I, 2 Case Sudies, (WA-RD 301.1).
    HOV Improvements on Signalized Arterials in the Seattle Area. Volume II, State of the Art Review, (WA-RD 301.2).
    HOV Improvements on Signalized Arterials in the Seattle Area. Volume IV, Simulation Planning and Evaluation, (WA-RD 301.4).

This abstract was last modified April 29, 2008