Sarnia Lambton History Rocks - 1937-1938 How They Built The Blue Water Bridge 1st Span

The Blue Water Bridge 1st span built between 1937 and 1938

The original span is a cantilever truss bridge with a total length of 6,178 feet (1,883 m) and a main span of 871 feet (265 m). The second, newer span is a continuous bowstring arch bridge with a total length of 6,109 feet (1,862 m) and a main span of 922 feet (281 m).

A US Port of Entry was established at the location in 1836, when a license to provide commercial ferry service between Port Huron and what then was known as Port Sarnia. The license was issued to a Canadian man named Crampton who operated a sailboat. In the 1840s, a man named Davenport, also from Port Sarnia, operated a pony-powered vessel. Steam-powered vessels and paddle wheelers soon followed, but the first vessel capable of carrying automobiles did not arrive until 1921.

The first bridge was fully opened to traffic on October 10, 1938. The lead engineer was Polish-born Ralph Modjeski. This bridge originally had two lanes for vehicles as well as sidewalks; the latter were removed in the 1980's to make room for a third lane for automobiles. The third lane for each direction started from the apex of the bridge in order to accommodate long lineups entering each sides' respective border crossings.

In 1928, Maynard D. Smith hired a Pennsylvania-based company named Modjeski and Masters to build what would become the Blue Water Bridge. Ralph Modjeski, a Polish-born engineer who would become known as "America's greatest bridge builder", served as lead engineer for the project. In developing a design, Modjeski faced obstacles posed by the U.S. Army Corps of Engineers, which sought to ensure that the St. Clair River remain navigable for military and commercial vessels. Bridge construction could not interfere with navigation, bridge builders could not use floating platforms, and the completed span was required to clear the water by 150 feet (46 m). Originally, Modjeski proposed a mammoth suspension-style bridge with tall towers and massive cable anchorages; however, because of the 150-foot (46 m) vertical clearance requirement for shipping, he opted instead for a cantilevered through-truss design.

In 1935, the Michigan Legislature passed a law (Public Act 147 of 1935 creating a State Bridge Commission to finance the design and erection of the main bridge structure of the Blue Water Bridge. The commission was approved by the United States Congress in August 1935 (Public Law 411 of 1935). The law permitted the commission to sell bonds that would be repaid by the revenue from the tolls ($0.25 toll for travelers) collected within 30 years. When the bridge and its associated bonds were paid off, Michigan Governor John Swainson used an executive order to cancel the $0.25 toll, eliminating the jobs of toll collectors, which included his own father.

In 1964, the eastern terminus of I-94 was completed at the foot of the Blue Water Bridge on the U.S. side. Traffic volumes steadily increased, spurred by the completion of Highway 402 in 1982 which provided a continuous freeway link to Highway 401 on the Canadian side. In 1984, I-69 was completed to Port Huron which meant that three freeways converged on the three-lane bridge.

In 1992, it was determined that traffic on the bridge had exceeded its rated capacity, so bridge authorities decided to add a second span in order to accommodate the higher traffic.