(
Archived Bridge Hunter;
Bridge Hunter; no Historic Bridges;
Satellite)
"Built 1878 by the American Bridge Works. for the CRI&P Railroad; Converted for vehicular use in 1938." The 600' (183m) long bridge has four wrought-iron spans of 149' (45m). [BridgeHunter]
I included the label "metalIron" since this bridge was made with wrought iron.
 |
Emily Willis posted
Harvey Railroad Bridge in Harvey, Iowa It’s an old railroad bridge that now serves as a narrow level B road over an old channel of the Des Moines River. During the summer, the trees nearly cover the top of the trusses, making a canopy over the bridge. It’s an interesting place to explore. You’re welcome to drive across the bridge or you can park just before the bridge and explore by foot. Brian Abeling / Iowa Road Trip |
 |
Dennis DeBruler commented on Emily's post
This 1912 topo map of the Pella Quadrant shows Harvey Island. The bridge used to belong to the Rock Island Railroad. |
Note that there are more tie-bars near the middle of the span than at the ends. That is because the tension forces of the lower chord are highest in the middle of the span.
 |
| 1017 Photo by John Marvig via BridgeHunter |
Unfortunately, this description is wrong. The CB&Q never crossed the river; and, according to a satellite map, that route still exists. Rock Island owned this bridge and abandoned it before 1938.
After the Des Moines Valley Railroad was completed in northeastern Marion County in 1866, the citizens of Knoxville began agitating for a railroad line that would link the southern and central parts of the county with a national railroad. A line named the Albia, Knoxville and Des Moines (AK&D;) Railroad was planned, and in 1870 Liberty, Indiana, Knoxville and Pleasant Grove Townships approved a special tax to help defray the construction costs for the proposed rail line. But the railroad fell short of completion, and after a period of litigation, the subscriptions and subsidies were acquired by the Chicago, Burlington and Quincy (CB&Q;) Railroad in 1875. With far better financing than the AK&D;, the CB&Q; was able to complete the line to Knoxville, with the first train rolling into town in December 1875. The following year the town of Harvey was platted near where the CB&Q; line crossed the Des Moines River. The railroad first employed ferries or a temporary bridge over the river at this point. In 1878, however, it contracted with the American Bridge Company of Chicago to fabricate a wrought iron truss as a permanent bridge for this crossing. The structure consisted of four pinned Pratt through trusses, supported by stone abutments and piers. It is not known whether American Bridge or the railroad itself erected the trusses, but the Harvey Railroad Bridge was completed by the time the line was completed through the county to Des Moines in 1879. It carried railroad traffic until 1938, when the county purchased the bridge and adjoining right-of-way and converted it into a county road. Although the river itself has been re-routed to the north, leaving the bridge with nothing to cross, the Harvey Railroad Bridge continues to function in place in unaltered condition. It is today a well-preserved example of early railroad truss construction in Iowa (adapted from Fraser 1992).
[ArchivedBridgeHutner]
