US Bridges

FM over Dd No. 976

Fair

Calhoun County, Iowa · 089341901 · Structure no. 000000000092820

Built
1938
87 years old, rebuilt 1990
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
53 ft
1 main span
Daily traffic
219
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Dd No. 976 is a steel stringer/multi-beam or girder carrying FM over Dd No. 976 in Calhoun County, Iowa. It was built in 1938 and reconstructed in 1990, so it is 87 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 219 vehicles a day, roughly 26% of them trucks, projected to reach 219 by 2043. The structure is 53 ft (16.2 m) long and 33 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesFM
CrossesDd No. 976
Location089341901
RouteCounty Highway 0
CountyCalhoun County
StateIowa
Coordinates42.51776, -94.89877
Functional classRural Major Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
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 geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.6 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length53 ft (16.2 m)
Longest span51 ft (15.5 m)
Deck width33 ft (10.1 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic219 (2022)
Projected traffic219 by 2043
Trucks26%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$180,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Dd No. 976 built?

It was built in 1938, making it 87 years old in 2025. It was reconstructed in 1990.

What condition is FM over Dd No. 976 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 FM over Dd No. 976 carry?

About 219 vehicles per day (2022 count), of which roughly 26% are trucks.

How long is FM over Dd No. 976?

The structure is 53 ft (16.2 m) long with a longest span of 51 ft (15.5 m) and a deck 33 ft wide.

Who owns FM over Dd No. 976?

It is owned by the County Highway Agency.