| Black Hawk Bridge | |
|---|---|
| Other name(s) | Lansing Bridge |
| Carries | 2 lanes of IA 9 and WI 82 |
| Crosses | Upper Mississippi River |
| Locale | Lansing, Iowa and Crawford County, Wisconsin, River Mile 663.4 |
| Maintained by | Iowa and Wisconsin Departments of Transportation |
| ID number | NBI 000000000013520 |
| Design | Melvin B. Stone |
| Total length | 1,653 feet (504 m) |
| Width | 21 feet (6 m), 2 Lanes |
| Clearance below | 68 feet (21 m) |
| Opened | June 17, 1931 |
| Daily traffic | 2,357 (2003) |
| Closed | August 17, 2011 (Temporarily) |
The Black Hawk Bridge spans the Mississippi River, joining the town of Lansing, in Allamakee County, Iowa, to rural Crawford County, Wisconsin. It is the northernmost Mississippi River bridge in Iowa.
Named for Chief Black Hawk, it is popularly referred to as the "Lansing bridge". It carries Iowa Highway 9 and Wisconsin Highway 82.
This riveted cantilever through truss bridge (other examples) has one of the more unusual designs of any Mississippi River bridge. Construction started in 1929 and was completed in 1931. The designer and chief engineer was Melvin B. Stone. The McClintic-Marshall Company of Chicago erected the trusses. The steel came from the Inland Steel Company.
The Wisconsin approach has a long causeway over Winneshiek bottoms (sloughs, ponds, and backwaters) before ramping up to the bridge itself. The main shipping channel is on the Iowa side. The Iowa approach is rather abrupt, going from a 25 mph city street straight up a steep ramp onto the bridge.
Originally a privately built and operated bridge owned by the Iowa-Wisconsin Bridge Company, it was closed between 1945 and 1957, due to damage from ice damming, and lacking funds to repair the bridge, the company went out of business. The two states acquired the bridge and repaired it.
In August 2011 the bridge was once again closed for repairs.
The bridge has a sufficiency rating of 39.9%, which mainly reflects its obsolete nature. So far neither Wisconsin nor Iowa have seriously considered replacing the structure, because daily traffic counts do not support a new crossing. However, if the bridge was torn down or became unusable there would be a 63 mile gap between river crossings.
There is a commercially-sponsored webcam on the bridge, updated every 30 seconds during daylight. The 1999 movie The Straight Story includes aerial footage of Alvin Straight (played by Richard Farnsworth) driving a riding lawn mower across the bridge.
On August 17, 2011 During an inspection a crack was found in the floor beam under the bridge deck, the bridge was closed.[1] The bridge was reopened on August 23, 2011.[2]
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