I-35W's Collapse: A Sign of the Times

This article, a follow-up to an annual bridge condition inventory, makes the case that more money is needed urgently to fix bridges in the U.S.. The author points to the rapidly growing population and the need to upgrade the infrastructure to prevent greater congestion. Bridges built between 1945 and the 1960s may be at greatest risk. Engineers designed older bridges to be four times the estimated strength needed to allow for future increased weight and traffic, as well as design flaws. After 1945 costs of materials and shortages caused engineers to design bridges closer to their actual needs. Design and repair design flaws may have caused the collapse of the I-35W Bridge in Minnesota.