Sneak Peek: The NP‘s St. Louis Bay Bridge

The North Pecific Railorad’s St. Louis Bay Bridge photographed in August 1941 by John Vachon. The Wisconsin Draw is shown prominently in the foreground, with Interstate Island and the bridge’s Minnesota Draw behind it. [Image: Library of Congress]

As you drive over the Blatknik Bridge fro Duluth and Superior, if you look out the passenger window you can see a small island in the bay, often covered with ring-billed gulls and common terns during warmer months. Some call it Bird Island, but its technical name is Interstate Island. It is entirely man-made and once played a pivotal role supporting the first railroad bridge ever built spanning the bay between Superior and Duluth. Below is the story of that bridge, a sneak peek from our forthcoming book Twin Ports Trains: The Historic Railroads of Duluth & Superior 1870–1970. Enjoy!

The St. Louis Bay Bridge

The Northern Pacific Railroad had received a charter to build a bridge between Duluth and Superior in 1870, but the fallout of the Panic of ’73 had delayed the project. The project was revived in 1881, when engineers surveyed the bay to determine the best route. The railroad delayed construction of the bridge until January 1885, after its first two subdivisions were complete in Superior. Originally built of wood and iron, the bridge spanned a navigational channel adjacent to Rice’s Point, over which the railroad built a steam-driven swing-arm draw span. The span sat on a concrete pier and swiveled ninety degrees to create a hundred-foot space on either side of the span, allowing lake freighters of the day to pass “through” the bridge. Later a second swing-arm draw was added over a shipping channel closer to Superior.

The northern span would become known as the Minnesota Draw and the southern span the Wisconsin Draw; between them the bridge was supported by piers on a small, a five-acre man-made island dubbed Interstate Island. Trains left Rice’s Point running south on a single track that became a double track once it passed over the 250-foot-long Minnesota Draw. After crossing the center span and the 300-foot-long Wisconsin Draw, the line entered Superior on the west bank of Howard’s Pocket (a small natural bay west of Conner’s Point) running parallel to Banks Avenue one block east of the end of the Second Subdivision line. Once the bridge opened, NP would stop using the St.P&D line from Carlton to Duluth along the St. Louis River.

The bridge opened for traffic on July 6, 1885, and while the St. Paul Pioneer Press declared the event had ushered in “a new era in the history of the Lake Superior country,” there was little local fanfare. Under its charter, the NP had to allow trains from all other railroads that would operate in Duluth and Superior to use the bridge, but those other lines had to pay for the usage. This allowed other railroads that already had a foothold in Superior to cross into Duluth without the expense of building their own lines, keeping the bay from becoming a cluster of bridges. Thanks to the bridge, in 1885 the Chicago, St. Paul, Minneapolis & Omaha Railroad—aka the Omaha Road—worked out a trackage-rights agreement with the NP and became the first railroad other than the St.P&D and NP to provide service to and from Duluth. Other railroads would enter trackage-rights agreement to use the bridge throughout its lifetime, including the Duluth, South Shore & Atlantic and Great Northern.

The bridge had its limitations. Because it had two swing spans that were operated independently—one might be opened while the other was closed—each train that crossed had to be short enough to fit between the spans in case it had to wait for a span to open. This limited the length of trains to a locomotive, a caboose, and 28 forty-foot cars.

The bridge also allowed commuters to cross between Duluth and Superior with much more ease aboard a St.P&D passenger train; prior to the bridge opening, getting from one city to the other required taking a ferry boat in the warmer months and a horse-drawn sledge in the winter.

Pedestrians were initially allowed to cross the bridge by foot, but the practice ended in August 1885. The bridges contained no walkways for people so they had to walk directly on top of the tracks—a very dangerous practice. The Duluth Daily Tribune speculated that the policy was implemented to increase ridership. By April 1886 about two hundred people used the bridge to commute between Duluth and Superior every day. Commuter traffic dropped off considerably when the Interstate Bridge—which featured a lane for streetcars and a sidewalk—opened in 1898.

In 1906 the federal government ordered both the Minnesota and Wisconsin Draws to be enlarged to both accommodate larger freighters and provide more margin for safety. Work began in 1908 on two entirely new all-steel draw spans. When completed, the new Minnesota Draw was 425 feet long, 175 feet longer than its predecessor, while its counterpart to the south stretched to 479 feet, 174 feet longer than the 1885 span. Importantly, the space for shipping traffic when each span was opened increased from 100 to 175 feet, providing for much safer navigation. The work was completed at the end of May, after which the original spans were removed by Superior’s Whitney Brothers, which took just four days to remove the entire 1885 Wisconsin Draw.

The bridge served for nearly one hundred years before Burlington Northern—NP’s successor—closed it on June 1, 1984. Since then all railroad traffic between Duluth and Superior has crossed St. Louis Bay using the Grassy Point Bridge. Dynamite helped demolition crews remove the Minnesota and Wisconsin drawbridges in September 1986. Interstate Island is still a feature of St. Louis Bay, although today it is often referred to as Bird Island for the ring-billed gulls and threatened common terns that populate it throughout the warmer months.

The latest idea for the cover for Twin Ports Trains (like the book itself, it’s a work in progress…).