Estimating The Supply And Demand For Commercial Heavy Truck Parking On Interstate Highways

The increasing number of trucks traveling on Virginia highways has led to a growing demand for public rest areas and private truck stops. This study developed a methodology to determine the supply and demand for commercial heavy truck parking using I-81 in Virginia as a case study. In this study, supply was defined as the number of parking spaces available for large truck parking, and demand at a given time was defined as the sum of the parking accumulation and the illegal parking. Extensive data on the characteristics of large truck parking including parking duration and accumulation for different times of day were obtained. Data were obtained at 14 public rest areas and 29 private truck stops. Detailed information was also obtained on the characteristics of each truck stop and rest area, including the location; number and types of parking spaces; and availability of other facilities, such as restaurants and showers. Two types of questionnaire surveys were conducted. The first involved truck drivers, and the second involved truck stop managers/owners. The data collected were used to develop models to describe the relationship between parking accumulation and independent variables such as traffic volume on the highway, truck percentage, parking duration, and the distance of a truck stop from the interstate. The models developed were then used to estimate demand in 10 and 20 years. Any shortfall in supply with respect to the estimated demand was then determined for each truck stop and the entire highway. The results indicated that the existing maximum demand is 2,947 parking spaces, which exceeds the supply by 309 spaces. This deficiency will increase to 1,193 and 1,463 spaces in 2010 and 2020, respectively, if the number of parking spaces for large trucks does not increase.