2 votes

RI - Big Sioux River Bridge



Interestingly, the river channel that once served as the boundary between Iowa and South Dakota has shifted to the west and is slowly moving away from the piers that once spanned the main channel. As the river erodes the west bank, it exposes more and more of the remnants of the long timber pile trestle that formerly served as the west approach. There now stands a long line of stumps in the channel that at one time were firmly driven into dry ground. The row of stumps leads right into the west bank, where they were probably chopped off at ground level during the bridge's demolition. It is fascinating to see how nature is slowly bringing more of this old bridge's remains into focus. Had the Rock Island survived until the present, and if this line had not been abandoned, the railroad's engineers and maintenance-of-way department would surely have their hands full keeping the Big Sioux River from bypassing their bridge!


Total length is approximate


Lost DPG bridge over Big Sioux River on former Rock Island RR
Lincoln County, South Dakota, and Lyon County, Iowa
Demolished and removed with piers remaining
Abandoned and removed ca. 1972
- Chicago, Rock Island & Pacific Railroad (CRIP (1866-1920); RI (1920-1975) ROCK (1975-1980))
3 x 50' DPG
Timber Pile Trestle approaches
Length of largest span: 50.0 ft.
Total length: 700.0 ft.
Approximate latitude, longitude
+43.46009, -96.59352   (decimal degrees)
43°27'36" N, 96°35'37" W   (degrees°minutes'seconds")
Approximate UTM coordinates
14/694681/4814722 (zone/easting/northing)
Quadrangle map:
Inventory number
BH 73839 (Bridgehunter.com ID)

Update Log 

  • October 1, 2016: Added by Dylan VanAntwerp


  • Dylan VanAntwerp - dylan_vanantwerp [at] live [dot] com