<P> 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 . During the debate over the form of the second span, five possible designs were proposed from 1994--1995 . Over half of public opinion had mostly favored a duplicate of the first bridge, while the cable - stayed bridge came in second with around 21% . The Blue Water Bridge Authority had rejected both designs, due to the duplicate creating a false sense of history, while the cable - stayed option was feared to overshadow the existing bridge . Another cost - effective but unpopular design was the parallel truss . The continuous - tied arch design, which was a distant third place in polls, was chosen for two reasons . One was that it blends in with the original span yet stands out on its own, and the other is lower maintenance costs because fewer spans are involved . </P> <P> The twinning project was a combined effort between Modjeski & Masters (American engineers) and Buckland & Taylor Ltd . (Canadian engineers). During the construction, two temporary masts were erected to assist in the construction of the tied arch; the towers were painted red and lighted, enabling them to be seen from afar . The approaches to the new bridge use box girders, compared to the original which hold up the road deck with trusses . </P> <P> The second three - lane bridge, just south of the first bridge, opened on July 22, 1997 . The first bridge was immediately closed for extensive renovation . During this period, the new span used a three - lane configuration reminiscent of the one employed on the original bridge . A flyover ramp on the U.S. side temporarily diverted westbound traffic from the new bridge to the toll plaza, which was blocked off after the original bridge was rehabilitated . The original span was reopened on November 13, 1999, making the Blue Water Bridge the largest infrastructure - crossing project in North America . </P> <P> In 2007, in accordance with Federal Identity Program requirements, the Blue Water Bridge Authority agreed on a name for the federal Crown corporate organization: Blue Water Bridge Canada . </P>

When was the second blue water bridge built