US Bridges

FM SW Blk Dimnd over N Branch Old Mans Creek

Fair

Johnson County, Iowa · 079073009 · Structure no. 000000000204220

Built
1968
57 years old, rebuilt 2006
Condition
Fair
inspected May 2023
Type
Slab
Concrete Continuous
Length
103 ft
3 main spans
Daily traffic
650
2021 count
Owner
County
County Highway Agency

About this bridge

FM SW Blk Dimnd over N Branch Old Mans Creek is a concrete continuous slab carrying FM SW Blk Dimnd over N Branch Old Mans Creek in Johnson County, Iowa. It was built in 1968 and reconstructed in 2006, so it is 57 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 650 vehicles a day, roughly 15% of them trucks, projected to reach 650 by 2043. The structure is 103 ft (31.4 m) long and 31 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesFM SW Blk Dimnd
CrossesN Branch Old Mans Creek
Location079073009
RouteCounty Highway 0
StateIowa
Coordinates41.61499, -91.70488
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.
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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating37.8 US tons
Inventory rating29.3 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length103 ft (31.4 m)
Longest span38 ft (11.6 m)
Deck width31 ft (9.3 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic650 (2021)
Projected traffic650 by 2043
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM SW Blk Dimnd over N Branch Old Mans Creek built?

It was built in 1968, making it 57 years old in 2025. It was reconstructed in 2006.

What condition is FM SW Blk Dimnd over N Branch Old Mans 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 May 2023.

How much traffic does FM SW Blk Dimnd over N Branch Old Mans Creek carry?

About 650 vehicles per day (2021 count), of which roughly 15% are trucks.

How long is FM SW Blk Dimnd over N Branch Old Mans Creek?

The structure is 103 ft (31.4 m) long with a longest span of 38 ft (11.6 m) and a deck 31 ft wide.

Who owns FM SW Blk Dimnd over N Branch Old Mans Creek?

It is owned by the County Highway Agency.