The impacts that would result from providing "reserved capacity" for trucks rather than restricting trucks are considered in this study. In the extreme case, trucks would be allowed to travel in a dedicated or exclusive lane. A more moderate approach would be to provide a "cooperative" dedicated lane in which vehicles such as trucks and buses could share a common lane and yet be separated from general traffic.
The study determined the following. Reserved-capacity strategies for trucks would offer (1) nearly $10 million in annual travel time savings for the trucking industry, (2) a savings of about 2.5 minutes per average truck trip (less than 8 percent savings in trip travel time), and (3) almost $30 million in annual travel time savings for single-occupancy vehicles in the Seattle region. The difference in travel times between the reserved-capacity strategy that would add trucks to the existing HOV lanes and the one that would add an exclusive truck lane would be insignificant, providing little justification for the construction of an exclusive truck lane. In all likelihood, the impact of reserved-capacity strategies on safety would be small, depending on the particular reserved capacity strategy. Reserved capacity strategies for trucks would accelerate pavement deterioration in the reserved lanes, but the reduction in the pavement deterioration rates of the general purpose lanes might help to balance future reconstruction costs. Surveys of the general public and subsequent statistical analysis showed considerable resistance to reserved-capacity strategies for trucks. However, this resistance is not unlike that encountered when HOV lanes were first considered.
It is the recommendation of this study that the idea of reserved-capacity strategies for trucks continue to be presented to the trucking industry, to the public, and to other impacted agencies for discussion and consideration. The study showed that the adverse impacts of such strategies are easily manageable and there is at least potential for freight-productivity improvements.