Oakland Mills Bridge
Photos
The two spans when lighted by LED at night
Photo taken by Jason Smith in August 2011
BH Photo #212825
Description
The Oakland Mills Bridge is a long-span combination through and pony truss with seven steel stringers approaches and one Pratt pony approach span on the east end of the structures. Spanning the Skunk River south of Oakland Mills, the 358-foot bridge features pinned connections throughout and is supported by a stone and timber substructure. The bridge's history may be traced to the summer of 1876, when county officials advertised for bids for the construction project. The Missouri Valley Bridge and Iron Company of Leavenworth, Kansas, was ultimately awarded the construction contract with prices set at $15.25 per lineal foot and $7.90 per cubic yard for masonry work. The approximate cost of the bridge therefore amounted to close to $12,000. Using steel components rolled by the Pennsylvania firm Phoenix Iron Company, the bridge was completed by MVB&I under the supervision of county engineer John Schreiner. Although closed to vehicular traffic today, the Oakland Mills Bridge is a popular spot for picnickers in Oakland Mills State Park, where the bridge retains a high degree of structural integrity. In the early 1880s, the pin-connected Pratt truss superseded the bowstring arch-truss as the iron bridge of choice for medium-span wagon crossings. Patented in 1844 by Thomas and Caleb Pratt, the Pratt design is distinguished by vertical members acting in compression and diagonals that act in tension. Virtually all of the major regional bridge fabricators manufactured Pratt trusses and marketed them extensively to Iowa's counties. This included the Missouri Valley Bridge and Iron Company. Thousands of pinned Pratt trusses were erected throughout Iowa, in both through and pony configurations, and many remain in service today. The Oakland Mills Bridge is distinguished as one of the earliest Pratt through trusses remaining in the state. It is an outstanding multiple-span example of this mainstay structural type [adapted from Crow-Dolby and Fraser 1992].Facts
- Overview
- Pratt through truss bridge over Skunk River on Pedestrian trail (formerly county road) at Oakland Mills State Park
- Location
- Oakland Mills, Henry County, Iowa
- Status
- Open to pedestrians
- History
- Built in 1876; converted to pedestrian bridge in the 1970s and became part of the state park
- Builder
- - Missouri Valley Bridge & Iron Co. of Leavenworth, Kansas
- Design
- The Oakland Mills Bridge consists of the following spans from north to south: 1 span three panel Pratt half-hip pony truss, multiple span wooden trestle, two span Pratt through truss (each with 7 panels) and one four panel (V-shaped) Pratt pony truss. All are pin-connected.
- Recognition
- Posted to the National Register of Historic Places
- Approximate latitude, longitude
- +40.93549, -91.61696 (decimal degrees)
40°56'08" N, 91°37'01" W (degrees°minutes'seconds") - Approximate UTM coordinates
- 15/616430/4532517 (zone/easting/northing)
- Quadrangle map:
- Mount Pleasant
- Inventory numbers
- NRHP 98000525 (National Register of Historic Places reference number)
BH 49512 (Bridgehunter.com ID)
Update Log
- November 18, 2013: Updated by Luke Harden: Added category "Park"
- August 29, 2013: New Street View added by Dave King
- March 30, 2013: New photos from Chris Gonnerman
- September 6, 2011: Added by Jason Smith
Sources
- Jason Smith - flensburg [dot] bridgehunter [dot] av [at] googlemail [dot] com
- Historic Bridges of Iowa
- The dire state of the Oakland Mills Bridge
- Chris Gonnerman
- Dave King - DKinghawkfan [at] hotmail [dot] com
Comments
The bridge we were looking at would not fit from stone pier to pier. Need 131 Feet....upper bluffton has a week or so. Did not want to replace a structure that was good like the pony, just looking at the trestle because of the pilings.
Why not replace the trestle and the northernmost pony truss span with the through truss structure and have the pony truss span available for reuse?
they need a 131' span to replace the trestle. Upper Bluffton won't fit so it is back to being doomed for her. It is quite sad. We tried very hard but I don't think we have the 12,000 to take her down and store her.
We'll see if we can find something suitable for this place but the engineers that like rehab are in on the game, so we will have to see where it goes.
The fact that the upper bluffton isnt scrapped is good news. The pony truss found a home in winneshiek and hopefully the high truss will before it falls to the scrappers. Winneshiek County has over 400 bridges and there arent alternative routes for most of them. Who cares where they go if they are saved. Not a perfect solution but certainly better than nothing. i was told a neighbor has the pony. TOOK it out intact. Wish it had been me.
If the through truss portion is being considered for the trestle span, that will on the one hand be a win-win situation for Iowa and the bridge itself but at the same time, it will be one less bridge for Winneshiek Co., which doesn't seem to care about HBs anymore. Let's hope that the idea is realized....
BTW, where exactly was the Queenpost truss relocated to?
I was talking about the trestle portion Jason. Sorry for the confusion with the word approach. It has the telephone pole piers for support. Still in thinking phase.
I was talking about the trestle portion Jason. Sorry for the confusion with the word approach. It has the telephone pole piers for support. Still in thinking phase.
The pony truss from Bluffton already found a new home up there in the neighborhood. The pony truss is still here at Oakland. Just trying to find a solution for a span that is due to be scrapped, Bluffton, and a substructure problem at Oakland.
The pony truss from Bluffton already found a new home up there in the neighborhood. The pony truss is still here at Oakland. Just trying to find a solution for a span that is due to be scrapped, Bluffton, and a substructure problem at Oakland.
If that was really going to be the case, then why not use the through truss portion of the UB for the trestle span and the queenpost for the approach span? That would be the best of both worlds; especially given the fact that the trestle bridge originally replaced the longest of the three through truss spans.
Just a thought for you and the engineer to chew on. ;-)
The approach span pilings are failing on Oakland Mills. They are measuring the length from pier to pier to see if Bluffton might fit there to replace the approach. The U.B. is to be scrapped in the next few weeks if we cant find the money or a new home.
RE: Upper Bluffton Bridge:
What do you mean by "even fit?" What is the current situation regarding the bridge?
Some pack rust throughout but over all a terrific bridge. Will see what they think of the idea. The Upper Bluffton not yet scrapped, although soon. They will speak with the engineers this week and see if it will even fit.
Interesting thought there. How about the rest of the bridge? How does it look from your stand point?
Out of the box solution,,,,,replace the rehab with another Pratt. That way you do not need the timber pole piers over the floodplain.....
Pony truss had unique cruciform bent outrigger verticals....
Out of the box solution,,,,,replace the rehab with another Pratt. That way you do not need the timber pole piers over the floodplain.....
Pony truss had unique cruciform bent outrigger verticals....
Out of the box solution,,,,,replace the rehab with another Pratt. That way you do not need the timber pole piers over the floodplain.....
Pony truss had unique cruciform bent outrigger verticals....
Our next project, or at least the next one I am going to go prequalify.
while on my way to Burlington with the proposal to study their bridge.
http://mt-pleasant-ia.villagesoup.com/news/story/oakland-mil...
Fun work, if you can get it. Here is hoping we are on a roll.
j
This page's URL is http://bridgehunter.com/ia/henry/oakland-mills/
My 3rd great grandfather, George Lawrence, Sr. was a stone mason and was involved in building this old Oakland Mills bridge. I had the opportunity to see it last Fall while doing my genealogy when I was visiting some old friends who happened to be living in Mt. Pleasant, Iowa. I was very pleased to see that it's still standing and being used as a pedestrain bridge and as a part of the State Park. I do hope it will be preserved and be part of the State Park for years to come.
Tracy Buckner