Marsh Engineering Company
The Marsh Engineering Company was a company that designed many significant bridges in the United States, including 7 that survive and are listed on the National Register of Historic Places. It was located in Des Moines, Iowa.
The firm's principal engineer was James Barney Marsh (1856–1936), an engineer and bridge designer born in North Lake, Wisconsin. He was a graduate of Iowa.
- Marsh Concrete Rainbow Arch Bridge, Minnesota, is a reinforced concrete through arch bridge, built in 1911 the same year that Marsh obtained a patent for his design.
Cotter Bridge in 1988
- Cotter Bridge, constructed in 1930, is the only bridge built by Marsh Engineering Company of Des Moines, Iowa in the state of Arkansas. It brings U.S. Route 62, over the White River, and opened up a large area of the Ozarks for recreation.
Henley Street Bridge, in Knoxville, TN
- Henley Street Bridge, in Knoxville, Tennessee, designed in 1930
The NRHP-listed bridges by the firm are the Cotter Bridge and also:
- Rainbow Arch Bridge, CO 52, Fort Morgan, Colorado
- Marsh Concrete Rainbow Arch Bridge, CR 101 over Little Cottonwood River, Courtland, Minnesota
- Dunkerton Bridge, Town street over Crane Creek, Dunkerton, Iowa
- First Avenue Bridge, US 151 over Cedar River, Cedar Rapids, Iowa
- Mederville Bridge, County road over Volga River, Mederville, Iowa
- Squaw Creek Bridge, 2 110th St. and V Ave. over Squaw Creek, Ridgeport, Iowa
Also, the Rainbow Arch Bridge at Valley City, North Dakota, was NRHP-listed but was later removed.
The Wilson River Bridge, near Tillamook, Washington, and others like it in Washington was designed by Conde McCullough, who had been employed at Marsh Engineering Company during the 1910s.