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Pilot Grove Park Bridge

Photos 

Photo taken by Historic American Engineering Record

BH Photo #115222

Map 

Description 

In January 1876, the Montgomery County Board of Supervisors received a petition from S.M. Smith and others for a new bridge over the Nodaway River south of Grant. The board at first laid the petition aside, but reconsidered it late that year. In June the board ordered the construction of a 70-foot iron span at this point, along with a 100-foot iron span over the Nishnabotna River and another bridge across Seven Mile Creek. A month later, the supervisors awarded contracts for the Nishnabotna and Nodaway river bridges t, the former to the Canton Bridge Company for $1,975 and the latter to the Missouri Valley Bridge and Iron Works for $1,000. The Leavenworth, Kansas firm fabricated a bowstring arch-truss and erected it that year. With its laced channel upper chords, iron bar lower chords and star iron verticals and outriders, the Nodaway River Bridge typified Missouri Valley standard bridge design of the period. The small-scale structure carried vehicular traffic until I was moved to Pilot Grove County Park around 1968. It now carries pedestrian traffic over the arm of a small pond. The bowstring arch-truss was the iron span of choice for Iowa counties in the late 1860s and 1870s. Marketed extensively by such industry giants as the Wrought Iron Bridge Company and King Iron Bridge and Manufacturing Company of Ohio, and the Missouri Valley Bridge and Iron Company of Kansas, these often-patented bridge forms featured a wide range of span lengths, economical fabrication cost and relatively quick erection. The proliferation of the bowstring corresponded with the initial development of Iowa's road system, and as a result, perhaps thousands of these prototypical iron spans were erected throughout the state. The bowstring design had some rather severe structural flaws, however, and it was superseded by the pin-connected truss in the early 1880s. Through subsequent attrition, almost all of Iowa's bowstrings have since been replaced and demolished. Although it no longer functions as designed in its original location, the Nodaway River Bridge is a historically and technologically significant resource in the interpretation of early Iowa transportation development [adapted from Fraser 1991].

Facts 

Overview
Relocated bowstring pony truss bridge in Pilot Grove County Park
Location
Montgomery County, Iowa
Status
Open to pedestrians
History
Built 1876 by the Missouri Valley Bridge & Iron Co.; relocated 1968
Builder
- Missouri Valley Bridge & Iron Co. of Leavenworth, Kansas
Design
Bowstring pony truss
Dimensions
Span length: 70.0 ft.
Total length: 70.0 ft.
Recognition
Posted to the National Register of Historic Places on May 15, 1998
Also called
Nodaway River Bridge
Approximate latitude, longitude
+41.14622, -95.04296   (decimal degrees)
41°08'46" N, 95°02'35" W   (degrees°minutes'seconds")
Approximate UTM coordinates
15/328559/4557000 (zone/easting/northing)
Quadrangle map:
Griswold NE
Inventory numbers
NRHP 98000494 (National Register of Historic Places reference number)
BH 36706 (Bridgehunter.com ID)

Update Log 

  • November 22, 2013: New photo from Luke Harden
  • December 3, 2011: Updated by Frank Hicks: Added GPS coordinates
  • June 16, 2008: New photos from Historic American Engineering Record

Sources