Applying the Least-Cost Transportation Model to Estimate the Effects of Major Transportation System Changes: Case Study of Dam Breaching on the Snake River

In studies conducted between September 1998 and March 2000, estimates were made of economic costs and benefits resulting from the loss of commercial barge navigation on the Snake River. These analyses estimated the effects on producers, agricultural production levels, transportation providers, highway and railroad infrastructure costs, and changes in fuel efficiency and emissions because of transportation mode shifts, based on a single least-cost transportation model (LCTM) that simulated the transportation patterns for wheat and barley in eastern Washington. An LCTM, such as the one used in these studies, can answer many of the critical questions about the effects of major changes to transportation systems and their users. Given its flexibility and sophistication, LCTM is an appropriate tool for predictive modeling when decision makers must consider the costs and benefits of a proposed transportation project or system modification. Although agricultural economists often use LCTM in their research, few transportation planning analysts apply this tool. The application of LCTM to transportation planning is illustrated by analyzing the economic effects likely resulting from changes to the transportation system in the Pacific Northwest related to the proposed breaching of four dams on the Snake River.