The managed lane concept is currently being considered on several major freeway projects in Texas cities. A managed lane facility is defined as one in which freeway efficiency is increased by packaging various operational and design actions, while maintaining the flexibility to adjust operations at any time to match regional goals. The pricing treatments on the Katy and Northwest HOV lanes in Houston represent the first managed lanes implemented in Texas, and two of the four operating HOT lanes in the country. While these current operational strategies are operating on existing facilities, new freeway projects now under development in Texas, however, are not retrofit efforts. Rather, they are major freeway expansions with multiple express lanes. As a new approach to operating freeways as a flexible and dynamic system, the concept of managed lanes has only been tested on a limited basis. The projects are moving forward rapidly despite wide gaps in the current knowledge base. The Texas Department of Transportation (TxDOT) is funding a multiyear research effort to address the unanswered questions and explore the complex interrelated issues involved with designing and operating managed lane facilities. This paper highlights the ongoing efforts of that research effort, which includes topics such as: operational effects of access design, design considerations for pricing managed lanes, concept marketing, decisionmaking guidance based upon targeted user groups, legislative issues, financing, geometric design, and enforcement. It will also discuss future research addressing traffic control devices, traveler information, interoperability, and incident management.
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