Called the Red Bridge locally, this medium-span truss carries a gravel-surfaced county road across the South Skunk River south of Reasoner in Fairview Township. Jasper County records indicate that the bridge was constructed at this location in 1892. Local bridge contractor H.S. Efnor held the county's annual bridge construction contract for that year, and he erected this bridge by September 1892 for $3,515.34. The bridge functioned as built until it was extensively damaged by flooding in 1947. The county then replaced one of the structure's original steel cylinder piers with concrete and added a pony truss approach span. The Red Bridge has functioned since in essentially unaltered condition.
The Pratt and Warren truss configurations were both developed in the 1840s, but it was the Pratt that received the most widespread use in the late 19th century. The reasons for this probably relate to the versatility of the pin-connected Pratt for different span lengths and its easier erection using timer falseworks. Although they later superseded the Pratt when the state highway commission developed its standard bridge designs in 1913, Warren trusses were rarely built in the 19th century; only a few pin-connected examples of this structural type were ever constructed Iowa. All but a handful of these have subsequently been razed. The Red Bridge is thus technologically significant as an intact example of this exceedingly rare structural type. Although substantially altered by the addition of the pony truss approach span, the bridge is an important and uncommon remnant of early Iowa transportation [adapted from Fraser 1990].
- Through truss bridge over South Skunk River on Red Bridge Street
- Jasper County, Iowa
- Closed to all traffic with north approach span collapsed.
- Future prospects
- Approach span collapsed in Spring 2013. Future uncertain as bridge is fenced off from over 1/2 mile on each end.
- Built ca. 1890
- - H.S. Efnor of Newton, Iowa (Contractor)
- Pinned/riveted warren through truss
Length of largest span: 120.1 ft.
Total length: 212.0 ft.
Deck width: 16.1 ft.
Vertical clearance above deck: 13.0 ft.
Posted to the National Register of Historic Places on May 15, 1998
- Approximate latitude, longitude
- +41.54095, -93.02123 (decimal degrees)
41°32'27" N, 93°01'16" W (degrees°minutes'seconds")
- Approximate UTM coordinates
- 15/498229/4598810 (zone/easting/northing)
- Quadrangle map:
- Land survey
- T. 78 N., R. 19 W., Sec. 23
- Inventory numbers
- IA 195700 (Iowa bridge number)
NRHP 98000521 (National Register of Historic Places reference number)
BH 13745 (Bridgehunter.com ID)
- Inspection (as of 03/2007)
- Deck condition rating: Critical (2 out of 9)
Superstructure condition rating: Serious (3 out of 9)
Substructure condition rating: Critical (2 out of 9)
Appraisal: Structurally deficient
Sufficiency rating: 17.3 (out of 100)
- Average daily traffic (as of 2006)
- December 4, 2016: Updated by Dylan VanAntwerp: Removed category "Skunk River"
- October 17, 2016: Updated by Dana and Kay Klein: South Skunk
- September 1, 2013: Updated by Jason Smith: Updated information on the bridge
- June 25, 2013: Updated by John Marvig: Bridge is scheduled for demolition
- June 25, 2013: Updated by Luke Harden: Doomed
- October 11, 2012: Updated by Jason Smith: Added categories "pin and riveted connections", "A-frame portal"
- July 26, 2011: Updated by Luke Harden: Changed name, added description, added photograph