Black Hawk Bridge

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Black Hawk Bridge
View from northwest, showing Wisconsin shore, with a barge crossing underneath (Library of Congress/HAER)
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)
AADT	2,357 (2003)
Opening date	June 17, 1931
Coordinates	43°21′55″N, 91°12′54″W

For other uses of Blackhawk/Black Hawk, see Black Hawk.

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.

The Black Hawk Bridge at dusk, looking northeast. Unfortunately the decorative lights weren't illuminated that night

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.

Aerial view looking north, January 14, 2001, with River at floodstage; click to enlarge. (USGS, Upper Midwest Environmental Sciences Center)

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.

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 has aerial footage of the Richard Farnsworth character driving a riding lawn mower across it.