Minnesota Highway 100 Railroad Bridge

In 1871, the Minneapolis & St. Louis Railway began construction of 28 miles of new railroad, extending from Minneapolis, Minnesota to Merriam Junction in Scott County. By 1878, the line would be extended an additional 93 miles to the Minnesota/Iowa border south of Albert Lea, where it would connect with previously constructed lines extending into Iowa. The Minneapolis & St. Louis Railway would be reorganized into the Minneapolis & St. Louis Railroad (M&StL) in 1895. Between 1901 and 1902, the M&StL would realign a significant portion of the route between Hopkins and Chaska, reducing the steep grades on Chaska Hill. The route would become the backbone of the M&StL system, as it would later acquire Iowa Central Railway, and grow into a medium sized system, connecting the Twin Cities to Peoria and Des Moines. The M&StL would later reorganize as the Minneapolis & St. Louis Railway in approximately 1920.

The M&StL was often in financial trouble, and would be purchased by the Chicago & North Western (C&NW) in 1960. The C&NW preferred this segment of track, as it gave a direct connection between the Twin Cities and the mainline in Iowa. When the C&NW purchased the parallel Rock Island line in 1983, this line became redundant. In 1984, the segment between Montgomery, Minnesota and Waseca, Minnesota would be abandoned, and in 1986, the segment from Waseca to Hartland, Minnesota would be sold to the Dakota, Minnesota & Eastern Railroad (DM&E). Further abandonments came in 1991, when the segment between Minneapolis and Chaska was abandoned, and acquired by Hennepin and Carver Counties for future use. The route would be converted to the Minnesota River Bluffs Trail between Chaska and Hopkins, and converted to the Cedar Lake Trail between Hopkins and Minneapolis. In 1995, the C&NW would be purchased by Union Pacific Railroad. A portion of the Kenilworth Cooridor through Minneapolis would later have tracks reinstalled in the late 1990s to serve the Canadian Pacific Railway/Twin Cities & Western Railroad operations into Minneapolis.

In 2007, a small trestle along the Minnesota River would collapse under a freight train serving the United Sugars plant in Chaska. As a result, the segment from Merriam Junction to Chaska would be abandoned in 2008. DM&E also abandoned the Hartland to Waseca segment the same year. Carver and Scott Counties would reach an agreement with Union Pacific for the Chaska to Montgomery segment in 2011, and the bridge across the Minnesota River at Carver would be removed that year. The segment between Chaska and Carver would be converted to a trail in 2012, and future plans indicate a desire to extend the trail to Merriam Junction. Construction began on the Southwest Light Rail (Metro Green Line Extension) in 2018, which will utilize the former M&StL grade between Shady Oak Road in Hopkins and Minneapolis. Union Pacific continues to operate the Merriam Junction to Montgomery segment as the Montgomery Industrial Lead.