US Bridges

FM over Black Hawk Creek

Fair

Grundy County, Iowa · 088161502 · Structure no. 000000000164871

Built
1984
41 years old
Condition
Fair
inspected April 2024
Type
Slab
Concrete Continuous
Length
128 ft
3 main spans
Daily traffic
29
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Black Hawk Creek is a concrete continuous slab carrying FM over Black Hawk Creek in Grundy County, Iowa. It was built in 1984, so it is 41 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 29 vehicles a day, projected to reach 29 by 2044. The structure is 128 ft (39 m) long and 33 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM
CrossesBlack Hawk Creek
Location088161502
RouteCounty Highway 0
CountyGrundy County
StateIowa
Coordinates42.43165, -92.71019
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionApril 2024
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56 US tons
Inventory rating32.8 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length128 ft (39 m)
Longest span49 ft (14.9 m)
Deck width33 ft (10.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic29 (2022)
Projected traffic29 by 2044
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Black Hawk Creek built?

It was built in 1984, making it 41 years old in 2025.

What condition is FM over Black Hawk 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 April 2024.

How much traffic does FM over Black Hawk Creek carry?

About 29 vehicles per day (2022 count).

How long is FM over Black Hawk Creek?

The structure is 128 ft (39 m) long with a longest span of 49 ft (14.9 m) and a deck 33 ft wide.

Who owns FM over Black Hawk Creek?

It is owned by the County Highway Agency.