With new U.S. Highway status came great changes and improvements. In 1927, the steel truss Gillespie Dam Bridge was constructed over the Gila River next to the Gillespie Dam. Prior to the construction of the bridge, traffic utilized a concrete apron constructed at the foot of the dam to cross the river. At the time, the Gillespie Dam Bridge was the largest steel structure in the state of Arizona. In 1928, the section of US 80 through Telegraph Pass was constructed and would be paved by 1930. The paving work on the highway east of Douglas was under way as well by 1930. 1930 also marked the year catastrophic flooding washed out US 80 through the town of Wellton. The town itself was also mostly destroyed by the flood. This led to the highway department having to construct an entirely new alignment north of the older one. The town center of Wellton was also reconstructed on the new alignment. The new alignment became the main street of Wellton, and was named Los Angeles Avenue. In 1931, the Mill Avenue Bridge in Tempe was constructed to carry US 80 and US 89 across the Salt River. The Mill Avenue bridge replaced the earlier 1913 Ash Avenue Bridge, which had carried both highways between Phoenix and Tempe since 1926.