Mother Nature caused a massive traffic jam in the Valley in the spring of 1965. For the first time in 24 years, heavy winter snowfall in northern Arizona resulted in sustained high flows in the usually dry Salt River channel.
The water came primarily from its major tributary, the Verde River. The Verde had significantly less storage capacity behind its two dams, Horseshoe and Bartlett, than the four dams on the Salt River.
When Bartlett Dam, the downstream impoundment on the Verde, was nearing full capacity, the Salt River Project opened the dam’s spillways. The resulting water release washed out road crossings along the Salt River in the Valley.
Brief springtime flows in the Salt River through the city were not unusual, and road crossings were usually closed only for a few days. But, the high flows in spring of 1965 affected many crossings for months. Driving across the Salt River was limited to a few bridges, and was a time-consuming challenge.
One of the most affected intersections that wet spring was where U.S. Highway 87, or Country Club Drive, crossed the Salt River.
The Arizona Highway Department, the forerunner of ADOT, let out bids for a project to improve the crossing in the late summer of 1965. Sanner Contracting won the $128,357 award to construct a pipe bridge. The company immediately began work where the highway crossed the river curving into McDowell Road, running west to Scottsdale. This river crossing carried both local commuters and long-distance traffic.
The Arizona Highway Department conceived and designed a roadway built over a series of giant pipes, which would convey the Salt River’s flows based on a 100-year flood event.
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This article originally appeared in the Arizona Contractor & Community magazine, Jan/Feb 2020 issue, Vol. 9, No.1. The Arizona Contractor & Community magazine is a bi-monthly publication.