A makeshift bridge was built for streetcar passengers and pedestrians at Lyndale Avenue during excavation of the 29th Street Track Depression from 1912–16. Below the bridge is a train of side-dump railroad cars, which carried loads of dirt to the swampy wasteyard of Bass Lake in St. Louis Park. Photo courtesy of the Minnesota Historical Society

In the years before 1912 — when railroad crews began to carve a 20-foot-deep, three-mile-long strip out of the city’s belly — most of the trains traveling the Milwaukee Road from Chicago to Seattle would roll through South Minneapolis alongside 29th Street.

At each of 25 intersections — from James Avenue to Hiawatha — the sound of an approaching train would prompt a man holding a large white flag to emerge from a little shack. Most of these flagmen had retired or been injured from regular railroad work, and their job was to serve as the city’s crossing guards — hand-lowering the gates and signaling for pedestrians, automobiles, horse-drawn carriages and electric streetcars to stop.

Between trains, a number of flagmen spent their time gardening, and the 29th Street corridor became known for its lush landscaped patches, where the amateur horticulturalists grew pansies, nasturtiums, bachelor’s buttons, climbing vines, sunflowers and potatoes.

“I guess the men become lonesome stationed on these crossings all day without steady work to keep their minds occupied so they find pleasure in keeping these little gardens and flower plots,” a flagman named I.H. Graft told the Minneapolis Tribune in 1913.

The construction of the 29th Street trench eliminated the need for these flagmen, the historian Tom Balcom said during a Sept. 30 lecture on the history of the Midtown Greenway. Balcom read from John Luecke’s 2010 history book, “More Milwaukee Road in Minnesota,” during the lecture, which was organized by the Linden Hills History Study Group.

“The crossing guards were either released or reassigned and the shanties were closed and, with their attendant gardens, eventually removed,” Balcom read, adding: “If you ride the Greenway at all, you’ll know that some of those gardens have reappeared.”

Lowering the tracks

After the Milwaukee Road’s transcontinental line was completed in 1909, traffic in Minneapolis increased dramatically, with about two dozen freight and passenger trains steaming through Midtown every day. Though the trains were kept to 6 mph, the 33 at-grade street crossings posed a danger to the city’s more than 300,000 residents.

“There was a surge of accidents resulting in injuries and deaths,” Balcom said. Streetcars crossed the train tracks at Lyndale, Nicollet, 4th, Chicago, Bloomington and Cedar avenues, and many worried about the risk of a catastrophic collision.

A 1909 proposal by the Milwaukee Road to close 19 city streets and depress 14 others was met with widespread derision, so the railroad suggested a more ambitious solution: the digging of a trench along 29th Street all the way from Humboldt Avenue to 19th Avenue — most of the distance between Lake of the Isles and the Mississippi River.

The City Council approved the 29th Street Track Depression in December 1910, though it angered industrial shippers, who had built factories, storehouses and warehouses along the rail line, and were displeased that the trench would literally cut the ground from under them.

There followed two years of litigation — between the industries and the railroad and between the city and the industries and between the railroad and the city. One case made it all the way to the U.S. Supreme Court, which ruled that “railroad corporations may be required, at their own expense, not only to abolish grade crossings, but also to build and maintain suitable bridges.”

A dirty ‘portage’

Excavation of the track depression caused a massive disruption in the lives of city residents. Streetcars would stop at the construction zone and passengers would get off and “portage” through the dust and muck of the trench before boarding a train on the other side.

“The portage could not have been enjoyable as it involved trudging down the embankment, crossing the … tracks amid the flurry of construction activity and then scaling the opposite bank where the connecting streetcar hopefully waited,” Luecke wrote. “One can only imagine the disgust the streetcar passengers voiced as they experienced this difficult connection.”

It took a crew of about 500 men four years to complete the trench. They worked west to east, and when they were finished digging, they had moved enough earth to fill the Foshay Tower more than five times.

The laborers had access to steam-powered pile drivers and bulldozers, and they loaded soil into side-dump railroad cars that carried the dirt to St. Louis Park, where it was tilted into the swampy wasteyard of Bass Lake. After the earth was removed, massive retaining walls needed to be built to hold back the trench’s north embankment.

Complicating the work were the oil, lumber and coal shipping buildings located next to the tracks. “If you’re building a trench and the industrial building is right next to the trench, how do you keep it from falling over into the trench?” asked Aaron Isaacs, a former Metro Transit planner and rail historian. “They had to jack it up and put in temporary [wooden] bracing and then they would fill it in with concrete.”

The railside industries adapted to the change in grade by using cranes and conveyor belts to lower materials down to the track and by constructing short rail spurs leading from the main track into their buildings’ lower levels. A huge grated door in the Greenway’s south wall can still be seen where an industrial spur once serviced the Buzza Company Building.

Concurrent with the excavation, 28 concrete bridges were constructed to span the trench. Clearance below the bridges was only 18 feet, so the City Council had to pass an ordinance banning trainmen from riding atop cars in Minneapolis.

Before rails could be placed, bulldozers first scraped and graded the track bed, Isaacs said. “Ties were manually dropped off flatcars and moved into place by hand. Special flatcars with gantry cranes moved the rails into place. The spikes may have been pounded into the ties by hand or by using compressed-air spike drivers. Hopper cars dumped the ballast onto the track and it was probably spread by track-mounted plows, then tamped down with compressed-air-powered machines.”

The 29th Street Track Depression was completed in 1916, and rail service continued through the corridor until 1998. The Midtown Greenway was opened to bike and pedestrian traffic in three stages between 2000 and 2006, and the Metropolitan Council has plans to someday build a light-rail line through the trench, adjacent to the bike-and-pedestrian trail.

A 140-year-old rail corridor

1881: The Chicago, Milwaukee, and St. Paul Railway begins running through Minneapolis along the route that is now the site of the Midtown Greenway.

1909: The Milwaukee Road’s transcontinental rail line is extended all the way to the Pacific Coast. Traffic in Minneapolis increases dramatically, with about two dozen freight and passenger trains steaming through Midtown every day.

1910: The Minneapolis City Council approves a plan to lower the 29th Street rail line below street level by digging a trench all the way from Humboldt Avenue to 19th Avenue.

1912–16: Crews work to dig the 20-foot-deep, three-mile-long 29th Street Track Depression. The finished trench ranges from 39–90 feet wide.

1917: The last of the 28 concrete bridges spanning the trench is completed. The bridges were designed by city engineer Frederick William Cappelen.

1998: The last Twin Cities & Western Railroad train runs through the 29th Street corridor.

2000–06: The Midtown Greenway is opened in three phases to bike and pedestrian traffic.

Future: The Metropolitan Council has tentative plans to build a light-rail line through the Greenway trench, adjacent to the bike-and-pedestrian trail. The line would connect the Blue Line’s Midtown station to the Green Line’s West Lake station.