US Bridges

FM over Drainage Ditch

Fair

Humboldt County, Iowa · 092270606 · Structure no. 000000000184650

Built
1940
85 years old
Condition
Fair
inspected November 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
32 ft
1 main span
Daily traffic
170
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Drainage Ditch is a steel stringer/multi-beam or girder carrying FM over Drainage Ditch in Humboldt County, Iowa. It was built in 1940, so it is 85 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 170 vehicles a day, roughly 17% of them trucks, projected to reach 170 by 2044. The structure is 32 ft (9.8 m) long and 25 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM
CrossesDrainage Ditch
Location092270606
RouteCounty Highway 0
CountyHumboldt County
StateIowa
Coordinates42.80804, -94.09011
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating54.7 US tons
Inventory rating32.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length32 ft (9.8 m)
Longest span30 ft (9.1 m)
Deck width25 ft (7.7 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic170 (2022)
Projected traffic170 by 2044
Trucks17%
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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM over Drainage Ditch built?

It was built in 1940, making it 85 years old in 2025.

What condition is FM over Drainage Ditch 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 November 2024.

How much traffic does FM over Drainage Ditch carry?

About 170 vehicles per day (2022 count), of which roughly 17% are trucks.

How long is FM over Drainage Ditch?

The structure is 32 ft (9.8 m) long with a longest span of 30 ft (9.1 m) and a deck 25 ft wide.

Who owns FM over Drainage Ditch?

It is owned by the County Highway Agency.