US Bridges

FM over D D #71

PoorPosted for load

Sac County, Iowa · 088360701 · Structure no. 000000000300760

Built
1930
95 years old
Condition
Poor
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
25 ft
1 main span
Daily traffic
26
2022 count
Owner
County
County Highway Agency

About this bridge

FM over D D #71 is a steel stringer/multi-beam or girder carrying FM over D D #71 in Sac County, Iowa. It was built in 1930, so it is 95 years old, older than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.

It carries about 26 vehicles a day, projected to reach 26 by 2044. The structure is 25 ft (7.6 m) long and 22 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesFM
CrossesD D #71
Location088360701
RouteCounty Highway 0
StateIowa
Coordinates42.4585, -95.08286
Functional classRural Minor Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

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.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating29.9 US tons
Inventory rating17.4 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length25 ft (7.6 m)
Longest span24 ft (7.3 m)
Deck width22 ft (6.6 m)
Roadway width21 ft (6.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic26 (2022)
Projected traffic26 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 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 over D D #71 built?

It was built in 1930, making it 95 years old in 2025.

What condition is FM over D D #71 in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in August 2024.

How much traffic does FM over D D #71 carry?

About 26 vehicles per day (2022 count).

How long is FM over D D #71?

The structure is 25 ft (7.6 m) long with a longest span of 24 ft (7.3 m) and a deck 22 ft wide.

Who owns FM over D D #71?

It is owned by the County Highway Agency.