Sketch Planning Analysis of HOT Lane Strategies

This paper describes how, as the costs of traffic congestion continue to increase, public officials and managers are seeking new strategies for managing congestion. Pricing the use of highway facilities is one way to help bring transportation supply and demand into balance. The preferred pricing strategy in the US at this time appears to be the implementation of high-occupancy toll (HOT) lanes. High-occupancy vehicles are allowed to use these lanes for free, while low-occupancy vehicles must pay a toll to use the HOT lanes. In effect, spare capacity on high-occupancy vehicle (HOV) lanes is sold off so that drivers with high values of time can choose to pay to bypass congestion. This paper describes the analysis of several HOT lane strategies on a freeway in Sacramento, California. Strategies analyzed varied on vehicle occupancy requirements for free use of the HOT lane. Because of resource limitations for planning, a sketch planning approach was adopted that made use of existing assignments from the regional travel model. Optimal tolls were determined based on projected road volumes and estimated travel times. This paper describes the analysis methods used, the insights provided by these methods, how the assumptions affected the results, and the shortcomings of the methods that need to be taken into account when assessing the results.