US Bridges

FM - Boston over Troublesome River

Fair

Cass County, Iowa · 077351003 · Structure no. 000000000100631

Built
1977
48 years old
Condition
Fair
inspected March 2024
Type
Slab
Concrete Continuous
Length
152 ft
3 main spans
Daily traffic
45
2022 count
Owner
County
County Highway Agency

About this bridge

FM - Boston over Troublesome River is a concrete continuous slab carrying FM - Boston over Troublesome River in Cass County, Iowa. It was built in 1977, so it is 48 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 6 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 45 vehicles a day, projected to reach 45 by 2044. The structure is 152 ft (46.3 m) long and 30 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesFM - Boston
CrossesTroublesome River
Location077351003
RouteCounty Highway 0
CountyCass County
StateIowa
Coordinates41.49004, -94.85798
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
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 inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating58.6 US tons
Inventory rating35.1 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length152 ft (46.3 m)
Longest span59 ft (18 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic45 (2022)
Projected traffic45 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$30,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was FM - Boston over Troublesome River built?

It was built in 1977, making it 48 years old in 2025.

What condition is FM - Boston over Troublesome River 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 March 2024.

How much traffic does FM - Boston over Troublesome River carry?

About 45 vehicles per day (2022 count).

How long is FM - Boston over Troublesome River?

The structure is 152 ft (46.3 m) long with a longest span of 59 ft (18 m) and a deck 30 ft wide.

Who owns FM - Boston over Troublesome River?

It is owned by the County Highway Agency.