Industrial History: US-67 Old and New (Clark) Bridge over Mississippi River in Alton, IL

Wednesday, February 1, 2017

US-67 Old and New (Clark) Bridge over Mississippi River in Alton, IL

(Bridge Hunter Old, Bridge Hunter New, no Historic Bridges, John Weeks III New, PBS Nova Transcript, Birds-Eye View)

I wrote an overview of the old bridges and dam to provide some context, which has some more photos.

HAER IL-31-36 from IL0555
DETAIL VIEW OF HIGHWAY BRIDGE, SHOWING RAILROAD BRIDGE AND LOCK AND DAM IN BACKGROUND, LOOKING NORTHEAST (UPSTREAM)

HAER IL-31-37 from IL0555
DETAIL VIEW OF HIGHWAY BRIDGE, SHOWING RAILROAD BRIDGE AND LOCK AND DAM IN BACKGROUND, LOOKING NORTHEAST (UPSTREAM)

Dave Hall commented on his posting
The auto bridge under construction in 1927/28

Dave Hall commented on his posting

1941 Aerial Photo from ILHAP

The old bridge was replaced not only because more traffic and pedestrian/bike lanes were needed, but because the spans were short and presented a significant navigation hazard after the new #26 Lock and Dam was built.

John Weeks III
John explains that this bridge is unusual because cables from both sides use the same tower.

John Weeks III
John explains that it is also unusual because all of the cables go over a saddle on top of the tower rather than attach to the sides of the tower. "While this is an innovative design, the saddle design has proven to have a serious problem, and is not likely to be attempted again in the near future." (I could not find any details on the problem.)

Kent Pillatsch posted

Clark Bridge across the Mississippi River Alton IL at the Golden Hour.

"The Clark Bridge is a cable-stayed bridge across the Mississippi River between West Alton, Missouri and Alton, Illinois. Named after explorer William Clark like the bridge it replaced, the cable-stayed bridge opened in 1994. It carries U.S. Route 67 across the river. It is the northernmost river crossing in the St. Louis metropolitan area.

The new $85 million, 108-foot-wide bridge (33 m) replaced the old Clark Bridge, which was only 20 ft wide (6.1 m).[1] The truss bridge was built in 1928. The new bridge carries two lanes of divided traffic in each direction, as well as two bike lanes. The old bridge carried only two lanes (similar to the upstream Champ Clark Bridge).

The bridge is sometimes referred to as the Super Bridge, and its construction process was documented in the 1997 NOVA episode Super Bridge, which highlighted the challenges of building the bridge, especially during the Great Flood of 1993. Designed by Hanson Engineers under contract to Illinois Department of Transportation (DOT), the Clark Bridge was the first in the United States in which "such a light steel-framed cable-stayed design was combined with a cable saddle type of pylon".[1] The bridge used 8,100 short tons (7,200 long tons; 7,300,000 kg) of structural steel; 44,100 cubic yards (33,700 m3) of concrete; and more than 160 miles (260 km) of cable wrapped with 4 acres (1.6 ha) of yellow plastic piping.[2]" wikipedea

John Weeks: Likely to be the only bridge ever built with that design. The saddle points are a problem that will result in the bridge having a much shorter lifespan than originally intended.

The new Tappan Zee Bridge is an example of the more traditional H tower design where each cable attaches to the side of the tower. (Although I think the flaring outwards of the H is a new wrinkle of the cable-stay design.)

New York State Thruway Authority from hdrinc

20150509 1066c
Parallel towers being built for the new I-65 bridge at Louisville, KY

Often called the "Super Bridge," the Clark Bridge links Highways 367 and 67 in Missouri to Alton, Illinois. It replaced the old Clark Bridge that served the area from 1928 to 1994. Design work on the new cable-stayed bridge was started in 1985, and construction began in 1990. The bridge, which has four traffic lanes and two bike lanes, spans 4,260 feet across the Mississippi River. It is made of 8,100 tons of structural steel, 44,100 cubic yards of concrete and more than 160 miles of cable wrapped with four acres of yellow plastic piping. Pilings that support the bridge were driven more than 140 feet below bedrock. Design criteria based on wind testing and geological studies were used to help make the bridge earthquake resistant. Total cost of the bridge was 118 million dollars, including the demolition of the old bridge. [GreatRiverRoad]

Update: During the 2017 flood, water covered the fixed part of the dam and was on part of the road on the levee on the MO side. On the Illinois side, the Great River Road and railroad by the bluffs were under water. And water was up to the mill.