US Bridges

FM 100th ST over Small Stream

Fair

Franklin County, Iowa · 091222901 · Structure no. 000000000157260

Built
1961
64 years old
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
44 ft
1 main span
Daily traffic
560
2022 count
Owner
County
County Highway Agency

About this bridge

FM 100th ST over Small Stream is a prestressed concrete stringer/multi-beam or girder carrying FM 100th ST over Small Stream in Franklin County, Iowa. It was built in 1961, so it is 64 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 560 vehicles a day, roughly 16% of them trucks, projected to reach 560 by 2043. The structure is 44 ft (13.4 m) long and 30 ft wide. If it were closed, the detour would be 19.3 mi (31 km).

Location

Open in Google Maps
CarriesFM 100th ST
CrossesSmall Stream
Location091222901
RouteCounty Highway 0
CountyFranklin County
StateIowa
Coordinates42.67369, -93.47693
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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56.3 US tons
Inventory rating36.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length44 ft (13.4 m)
Longest span43 ft (13.1 m)
Deck width30 ft (9.2 m)
Roadway width28 ft (8.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic560 (2022)
Projected traffic560 by 2043
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.3 mi (31 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was FM 100th ST over Small Stream built?

It was built in 1961, making it 64 years old in 2025.

What condition is FM 100th ST over Small Stream 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 100th ST over Small Stream carry?

About 560 vehicles per day (2022 count), of which roughly 16% are trucks.

How long is FM 100th ST over Small Stream?

The structure is 44 ft (13.4 m) long with a longest span of 43 ft (13.1 m) and a deck 30 ft wide.

Who owns FM 100th ST over Small Stream?

It is owned by the County Highway Agency.