In 1865, the U.S. government awarded 200,000 acres of land to the Portage Lake and Lake Superior Ship Canal Company to build a canal. (The U.S. government gave more acreage to the project that totaled around 450,000 acres upon the project’s completion.) It was a project that would take over 9 years to complete. The canal was created with the intention of connecting the Keweenaw Bay through Portage Lake with Lake Superior. This would save ships a tremendous amount of time and money!
Introducing the Portage Canal: In 1874 the canal was finished! It was 2 miles long, 100 feet in width, and 14 feet deep. (In 1935, it was widened to 500 feet in width.)
In 1875, a toll swing bridge was constructed between Houghton and Hancock. This lasted until 1901 when a steel swing bridge replaced it. In 1905, a ship crashed into the bridge causing the bridge to need significant repairs. The current bridge was constructed in 1959 at a total estimated cost of $12 million dollars. The lift bridge is capable of lowering down to a point of about 4 feet from the water to a maximum height of 100 feet.
Reference: Wikipedia/Portage Lake Lift Bridge: MTU Archives