US Bridges

FM over Big Slough Creek

Fair

Muscatine County, Iowa · 078042902 · Structure no. 000000000258461

Built
1980
45 years old
Condition
Fair
inspected September 2023
Type
Slab
Concrete Continuous
Length
127 ft
3 main spans
Daily traffic
40
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Big Slough Creek is a concrete continuous slab carrying FM over Big Slough Creek in Muscatine County, Iowa. It was built in 1980, so it is 45 years old, younger 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 40 vehicles a day, projected to reach 40 by 2043. The structure is 127 ft (38.7 m) long and 30 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesFM
CrossesBig Slough Creek
Location078042902
RouteCounty Highway 0
CountyMuscatine County
StateIowa
Coordinates41.52713, -91.34826
Functional classRural Minor 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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating57.5 US tons
Inventory rating33.5 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length127 ft (38.7 m)
Longest span49 ft (14.9 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (2022)
Projected traffic40 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost$30,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Big Slough Creek built?

It was built in 1980, making it 45 years old in 2025.

What condition is FM over Big Slough Creek 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 September 2023.

How much traffic does FM over Big Slough Creek carry?

About 40 vehicles per day (2022 count).

How long is FM over Big Slough Creek?

The structure is 127 ft (38.7 m) long with a longest span of 49 ft (14.9 m) and a deck 30 ft wide.

Who owns FM over Big Slough Creek?

It is owned by the County Highway Agency.