Black Hawk Bridge
Black Hawk Bridge | |
|---|---|
| Coordinates | 43°21′55″N 91°12′54″W / 43.36528°N 91.21500°W |
| Carried | 2 lanes of Iowa 9 / WIS 82 |
| Crossed | Upper Mississippi River |
| Locale | Lansing, Iowa and Crawford County, Wisconsin, River Mile 663.4 |
| Other name | Lansing Bridge |
| Maintained by | Iowa Department of Transportation |
| ID number | NBI 000000000013520 |
| Characteristics | |
| Design | Cantilever through truss |
| Total length | 1,653 feet (504 m) |
| Width | 21 feet (6 m), 2 lanes |
| Longest span | 653 feet (199 m) |
| Clearance below | 68 feet (21 m) |
| History | |
| Opened | June 17, 1931 |
| Closed | October 20, 2025 |
| Demolished | December 19, 2025 |
| Statistics | |
| Daily traffic | 2,357 (2003) |
| Toll | None |
| Location | |
Interactive map of Black Hawk Bridge | |
The Black Hawk Bridge spanned the Mississippi River, joining the town of Lansing, in Allamakee County, Iowa, to rural Crawford County, Wisconsin. It was demolished with explosives on December 19, 2025.
Named for Chief Black Hawk, it was popularly referred to as the "Lansing bridge". It carried Iowa Highway 9 and Wisconsin Highway 82. It was the northernmost Mississippi River bridge in Iowa.
This riveted cantilever through truss bridge had 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 bridge had five reinforced concrete piers. Pier 2 and Pier 3, which were the critical piers in the river, were founded on 143 timber piles, each at least 40 feet (12 m) long. The piles did not reach the river bedrock. Scour had been observed around and beneath the piers. Iowa DOT had dumped large stone against the bottom of the pier to maintain the bridge pier integrity.
The Wisconsin approach had 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 was rather abrupt, going from a 25 miles per hour (40 km/h) 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.