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FreightWaves Classics/ Infrastructure: Blue Water Bridge is a key US-Canada crossing

Bridge is a major artery for car and truck traffic between the two nations

The Blue Water Bridge. (Photo:

A major international crossing over the St. Clair River at the southern end of Lake Huron, Blue Water Bridge is located between Port Huron, Michigan and Point Edward, Ontario. When it fully opened to traffic during the fall of 1938, it became one of the fastest links between the Midwest and Ontario as well as the Northeast United States.

The (original) Blue Water Bridge is a cantilever truss bridge. Its total length is 6,178 feet; its main span is 871 feet long. The bridge was built as a joint project by the Michigan Department of State Highways (MDSH) and the Ontario Department of Highways (the present-day Ministry of Transportation of Ontario). MDSH became the Michigan Department of Highways and Transportation (MDHT) in 1973, and then was renamed the Michigan Department of Transportation (MDOT) in 1978.

Construction on the Blue Water Bridge in 1937. (Photo:
Construction on the Blue Water Bridge in 1937. (Photo:

Once the United States’ Interstate Highway System was developed, Blue Water Bridge connected both Interstate 69 and Interstate 94 with Canada’s Highway 402.  


A U.S. Port of Entry was established near the current location of the bridges in 1836. A license to provide commercial ferry service between Port Huron and what was then known as Port Sarnia was issued to a Canadian, who operated a sailboat between the two locations. In the 1840s, another Canadian “operated a pony-powered vessel.” Later, steam-powered boats and paddle wheelers were used. In 1921, the first vessel capable of carrying automobiles across the river began operations.

In 1928, the Pennsylvania-based firm of Modjeski and Masters was hired to build what would become the Blue Water Bridge. Ralph Modjeski was a Polish-born engineer who ultimately became known as “America’s greatest bridge builder.” Modjeski served as the lead engineer on the project. While he was developing the bridge’s design, Modjeski had to contend with requirements dictated by the U.S. Army Corps of Engineers. The Corps mandated that the St. Clair River remain navigable for military and commercial vessels. Therefore, construction of the bridge 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.” Modjeski’s first design was a suspension bridge with tall towers and massive cable anchorages. However, because of the 150-foot vertical clearance requirement for shipping, he changed his design significantly, developing a cantilevered through-truss design instead.

A ship steams under the unfinished Blue Water Bridge in 1938. (Photo:
A ship steams under the unfinished Blue Water Bridge in 1938. (Photo:

The Michigan Legislature passed a law in 1935 that created a State Bridge Commission to finance the design and construction of the bridge, and the U.S. Congress approved the commission later that year. The law permitted the commission to sell bonds to finance the construction; they were to be repaid by the revenue generated by a $0.25 toll collected for 30 years. Michigan Governor John Swainson used an executive order to eliminate the toll when the bridge and its associated bonds were paid off. (There are tolls on the bridge now, however.) 

The first Blue Water Bridge was opened to traffic on October 10, 1938. (Part of the dedication ceremony can be seen in the photo below, which is from the Digital Collections of the Wayne State University Libraries). The bridge originally had two lanes for vehicles and sidewalks. The sidewalks were removed in the 1980s for a third traffic lane. The third lane in each direction began at the bridge’s apex and was used to accommodate lines of vehicles entering the border crossings.

The eastern terminus of I-94 was completed at the foot of the Blue Water Bridge on the U.S. side of the bridge in 1964. In 1982, the completion of Canadian Highway 402 provided a continuous freeway link to Highway 401, one of Ontario’s busiest highways. Two years later, I-69 was completed to Port Huron. Traffic volumes steadily increased as the three freeways converged on the three-lane bridge.

A second bridge was needed

After more than four decades of use, American and Canadian transportation officials determined that another span for the Blue Water Bridge was needed due to increased traffic in the region. In a 1997 interview with the Port Huron-based Times Herald, MDOT project development engineer Charlie Jennett, stated, “It was not a question of if we needed a second bridge. It was where and when it would be built.”

The north (original) span of the Blue Water Bridge. (Photo: Chris Light/Wikipedia)
The north (original) span of the Blue Water Bridge. (Photo: Chris Light/Wikipedia)

Prior to building the second bridge, the customs and toll collection booths on both sides of the original bridge were “extensively reconfigured in the early 1990s.” On the U.S. side of the bridge, the “overpass crossing Pine Grove Avenue was replaced by a much wider embankment, which also added a four-story customs office building in the center.” The improvement on the U.S. side “necessitated the demolition of the original booths that had been in use since 1938” on the Canadian side of the bridge. These were appreciated for their Art Deco styling, but they were too low to accommodate semi-trailer trucks.

By 1992, traffic on the bridge had exceeded its rated capacity, so U.S. and Canadian bridge authorities made the decision to add a second bridge to accommodate the higher traffic.

After engineering studies and surveys by the Ministry of Transportation of Ontario and the MDOT, it was decided that the Second Blue Water Bridge would be constructed just south of the original bridge. 

The five original designs for the second bridge as designed by Modjeski & Masters. (Image:
The five original designs for the second bridge as designed by Modjeski & Masters. (Image:

The process to decide the design of the second bridge took place in 1994-95. Five possible designs were proposed By Modjeski & Masters. The continuous-tied arch design was chosen for two reasons – it  blended in with the original span yet had its own character and its design has lower maintenance costs because it had fewer spans. 

However, the selection of the continuous-tied arch proposal was unpopular with the local populations; critics regarded its design as “awkward.” This led the engineers to modify its design details to make it more complementary with the existing bridge. For example, concrete piers and a steel tower supporting the anchor span (rather than a more traditional concrete tower), “gave the bridge a less massive appearance, easing the difficult transition between the approach, anchor and main spans.” 

In addition, the engineers made “the main span attractive, but economical by settling on an innovative low arch design that merges the traffic deck with the bottom structural supporting steel for the portion of the bridge suspended over the water,” which “eliminated the need for expensive bracing and contributes to the graceful appearance of the structure.” In addition, the new bridge’s flattened arch more closely matches the old bridge. 

In regard to the new bridge’s approaches “the engineers selected concrete hammer-head piers over steel piers and deck trusses, not only for economical considerations, but they also give the new bridge a simpler look, making it easier to distinguish the old bridge from the new one” and “contributes to the clean lines of the new bridge and leaves the view of the old bridge’s deck trusses uncluttered.” 

The twin spans of the Blue Water Bridge. (Photo: Grace Sharkey/FreightWaves)
The twin spans of the Blue Water Bridge. (Photo: Grace Sharkey/FreightWaves)

Construction of the new bridge was a combined effort between Modjeski & Masters (the American engineers, and the firm that designed the original bridge) and Buckland & Taylor Ltd. (Canadian engineers). While the original bridge holds up the road deck with trusses, the approaches to the new bridge use box girders.

The second, newer span is a continuous bowstring arch bridge. It has a total length of 6,109 feet; its main span is 922 feet long. The new three-lane bridge, just south of the first bridge, opened just over 25 years ago (July 22, 1997).

The new bridge’s opening

Bobbi Welke, MDOT’s bridge project manager, oversaw construction of the U.S. section of the new bridge. “This was a team effort,” she explained to the Times Herald. “The skilled laborers, the professionals . . . everyone involved with this job has been terrific to work with. I couldn’t have asked for better people.”

Therefore, nearly six decades after the inauguration of the original Blue Water Bridge between Michigan and the Canadian province of Ontario, the Second Blue Water Bridge was opened to motor vehicles. 

Thousands of pedestrians on the Blue Water Bridge in 1997. (Photo:
Thousands of pedestrians on the Blue Water Bridge in 1997. (Photo:

However, 10 days before the bridge was opened to motor vehicle traffic, it was officially dedicated. The public officials taking part included Michigan Governor John Engler and Herb Gray, deputy prime minister of Canada.

In addition, approximately 200,000 people walked across the bridge the following day. On the U.S. side of the bridge, MDOT’s logistical efforts included oversight of public transportation arrangements for people wanting to walk across the span. The Times Herald reported, “Michigan Department of Transportation employees kept buses that shuttled people to the bridge flowing, and they did it with a smile.”

Modjeski and Masters prepared a design contract to replace and widen the deck, strengthen the steel superstructure, improve traffic signals and do general upgrades to the bridge. Construction support and inspection services were also provided. 
Modjeski and Masters prepared a design contract to replace and widen the deck, strengthen the steel superstructure, improve traffic signals and do general upgrades to the original bridge. Construction support and inspection services were also provided.

Rehabilitating the original bridge

Following the opening of the new bridge, the original was immediately closed for extensive renovations. Among the projects undertaken were the replacement of the bridge’s deck, guardrails and lighting. When the renovations were completed, the original bridge was reopened about 29 months later – on November 13, 1999. The construction of the Second Blue Water Bridge and the renovations to the original bridge made the Blue Water Bridge the largest infrastructure-crossing project in North America.

Since both spans opened

In 2011, construction projects began to widen and improve Canada’s Highway 402 and co-signed I-94/I-69 on the U.S. side approaching the bridge. The projects were completed in 2012, and they added dedicated lanes to separate Blue Water Bridge traffic from local traffic.

Both the U.S. and Canadian border stations are open 24 hours per day at the Port Huron-Sarnia border crossing. In March 2009, the Canadian government announced a US$10.8 million project to upgrade the Canada Border Services Agency border crossing facilities at the Blue Water Bridge. That project was completed in 2012. In addition, U.S. Customs and Border Protection upgraded its inspection facilities in 2011. In 2017, inspectors at Port Huron processed nearly 1.6 million cars and over 825,000 trucks.

The twin spans of the Blue Water Bridge. The newer span is in the foreground. (Photo: Optionbooter/wikimediacommons)
The twin spans of the Blue Water Bridge. The newer span is in the foreground. (Photo: Optionbooter/wikimediacommons)

The bridges today

The twin spans of the Blue Water Bridge are jointly owned and operated by the United States and Canada. MDOT is in charge of maintaining the American side, while Federal Bridge Corporation Limited (a Crown corporation of the Government of Canada) is responsible for the Canadian side.

Blue Water Bridge plays an essential role as an economic link between Canada and the United States. The two bridges are one of the four shortest routes of land travel between the U.S. Midwest and Northeast. They are also the second-busiest commercial crossing on the Canada-U.S. border (after the Ambassador Bridge at Detroit-Windsor,) and the fourth-busiest overall international crossing in Ontario in terms of total number of vehicles. In Canada, they are the third-busiest bridges after the Champlain Bridge in Montreal and the Ambassador Bridge.

FreightWaves Classics thanks,,, Wikipedia and Modjeski & Masters for information and photos used in this article.

Scott Mall

Scott Mall serves as Managing Editor of FreightWaves Classics. He writes articles for the website, edits the SONAR Daily Watch series, marketing material for FreightWaves and a variety of FreightWaves special projects. Mall’s career spans 45 years in public relations, marketing and communications for Fortune 500 corporations, international non-profits, public relations agencies and government agencies.