A Case Study of the Design Issues Associated with HOV toHOT Conversion

By the end of 2005 there will be six High Occupancy Toll (HOT) Lane facilities operational in the United States. In all but one of the six facilities, the HOT lanes are conversions from High Occupancy Vehicle (HOV) lanes. In addition to HOT Lanes that will be open later this year, there are many more around the United States that are currently being studied and evaluated. There are many issues to consider in the conversion from HOV to HOT lanes including: public support, tolling technology, design, environmental impacts, operations and maintenance and revenue collection. Because the HOT lane concept is new, each of these concepts is equally critical in ensuring that the conversion is viewed as a success. In 2003 the Washington State Department of Transportation was directed by their Transportation Commission to study the feasibility of the conversion of an existing HOV lanes facility to a HOT lane for the purposes of pilot project. Following the selection of the project corridor, the State conducted a feasibility study. To ensure the success of the pilot project, a sophisticated approach was followed for the selection of the Pilot Project corridor and of the design of the HOT Lane.