weight limits of the ISTEA freeze to a significantly expanded highway network in each State. This could prohibit flexibility and rationalization within individual States, and cooperation among adjacent States.
What would happen to western border trucking if Federal weight provisions were modified to accommodate freight moving in interstate and international commerce particularly in containers on NHS highways? The crossborder movement of international containers along I-5 between the Ports of Seattle, Washington and Vancouver, British Columbia is estimated to involve about 135 truck trips per day each way, about 15 percent of the total truck movement. Many of these movements take place on vehicles specially designed to handle fully loaded 40-foot containers within the weight distribution provisions of Bridge Formula B. Others occur on five- axle tractor-semitrailers, often experiencing overloads on the drive tandem axle. Some containers are moved crossborder in double-trailer combinations (for example, with one 40-foot container plus one 20-foot container, or three 20-foot containers together).
The option of using a six-axle tractor-semitrailer for container movements across the United States and Canada, within Washington, and to and from adjoining States could be expected to have a substantial response by industry. It would reduce the use of the existing, specially designed equipment now used for these movements.
There is some, probably very limited, movement of international containers between Alberta and Shelby, Montana along I-15 for trans-shipment on the Burlington Northern (BN) Railway pursuant to the special weight provisions of ISTEA. Since these movements now occur in Canadian configurations at Canadian weights (for example, a six-axle tractor-semitrailer at 96,000 pounds) and Canadian axle spreads, little change would be expected here.
There are also limited movements of international containers between northern Minnesota and Winnipeg, Manitoba and between the BN mainline through North Dakota and Winnipeg. Providing for the effective employment of six-axle tractor-semitrailers for these movements could encourage these exchanges and support trade corridor proposals such as those along I-29 and I- 35.