US Bridges

STH312 Eb(old STH1 over Chippewa River

Fair

Eau Claire County, Wisconsin · 1.2M N JCT Cth F · Structure no. B18013200000000

Built
1992
33 years old, rebuilt 1993
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
1,488 ft
10 main spans
Daily traffic
12,450
2021 count
Owner
State
State Highway Agency

About this bridge

STH312 Eb(old STH1 over Chippewa River is a steel continuous stringer/multi-beam or girder carrying STH312 Eb(old STH1 over Chippewa River in Eau Claire County, Wisconsin. It was built in 1992 and reconstructed in 1993, so it is 33 years old, younger than the Wisconsin average of 40.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 12,450 vehicles a day, roughly 3% of them trucks, projected to reach 14,940 by 2041. The structure is 1,488 ft (453.5 m) long and 52 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

CarriesSTH312 Eb(old STH1
CrossesChippewa River
Location1.2M N JCT Cth F
RouteState Highway 312
Coordinates44.84095, -91.50173
Functional classUrban Other Principal Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating86.4 US tons
Inventory rating51.8 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans10
Design loadHS 20
Structure length1,488 ft (453.5 m)
Longest span154 ft (46.9 m)
Deck width52 ft (15.8 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,450 (2021)
Projected traffic14,940 by 2041
Trucks3%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was STH312 Eb(old STH1 over Chippewa River built?

It was built in 1992, making it 33 years old in 2025. It was reconstructed in 1993.

What condition is STH312 Eb(old STH1 over Chippewa River in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in July 2023.

How much traffic does STH312 Eb(old STH1 over Chippewa River carry?

About 12,450 vehicles per day (2021 count), of which roughly 3% are trucks.

How long is STH312 Eb(old STH1 over Chippewa River?

The structure is 1,488 ft (453.5 m) long with a longest span of 154 ft (46.9 m) and a deck 52 ft wide.

Who owns STH312 Eb(old STH1 over Chippewa River?

It is owned by the State Highway Agency.