St. Charles Air Line Bridge
Photo taken by Steve Conro in September 2012
The St. Charles Air Line (SCAL) Bridge was the world’s longest and heaviest single-leaf bridge when completed in 1919. Designed by the acclaimed Chicago bridge engineer Joseph B. Strauss, the SCAL Bridge was built using many of the design principles as the Chicago & Northwestern Railway Bridge (constructed in 1908). However, the SCAL Bridge is significant because it is an excellent example of a “heel trunnion” bascule bridge, a design developed by Strauss specifically for long bascule spans.
-Commission on Chicago Landmarks, Historic Chicago Railroad Bridges
The Southern most bridge in the down position is the SCAL bridge and is still in use by the CNRR. The Northern, stored in the up position is the B&O/Chicago Terminal RR Bridge and is now abandoned.
- Railroad bascule bridge over the Chicago River near downtown Chicago
- Chicago, Cook County, Illinois
- Open to traffic
- Future prospects
- Facing possible closure/demolition
- Built in 1919, original length was 260 ft. -- later shortened to 220 ft. in 1930
- - Strauss Bascule Bridge Co. of Chicago, Illinois
- - Canadian National Railway (CN)
- Chicago & North Western Railway (CNW)
- St. Charles Air Line Railroad
- Strauss Trunnion Bascule
Length of largest span: 220.0 ft.
Total length: 2,000.0 ft.
- Approximate latitude, longitude
- +41.86110, -87.63456 (decimal degrees)
41°51'40" N, 87°38'04" W (degrees°minutes'seconds")
- Approximate UTM coordinates
- 16/447332/4634548 (zone/easting/northing)
- Quadrangle map:
- Inventory numbers
- HAER IL-67
BH 38237 (Bridgehunter.com ID)
- August 6, 2015: New photo from Douglas Butler
- October 30, 2014: New photo from Douglas Butler
- August 26, 2013: New photo from Douglas Butler
- August 21, 2013: New Street View added by Douglas Butler
- October 1, 2012: Updated by Daniel Hopkins: Added category "Railroad"
- September 30, 2012: Updated by Luke Harden: Added category "St. Charles Air Line Railroad"
- September 29, 2012: Updated by Steve Conro: Added categories "Canadian National Railway", "Navigable waterway"