US Bridges

FM over N Skunk River Overflow

PoorClosed to traffic

Mahaska County, Iowa · 076141001 · Structure no. 000000000236920

Built
1961
64 years old
Condition
Poor
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
178 ft
3 main spans
Daily traffic
370
2022 count
Owner
County
County Highway Agency

About this bridge

FM over N Skunk River Overflow is a steel continuous stringer/multi-beam or girder carrying FM over N Skunk River Overflow in Mahaska 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 poor condition with a lowest component rating of 0 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: closed to all traffic.

It carries about 370 vehicles a day, projected to reach 370 by 2043. The structure is 178 ft (54.3 m) long and 26 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesFM
CrossesN Skunk River Overflow
Location076141001
RouteCounty Highway 0
CountyMahaska County
StateIowa
Coordinates41.40847, -92.45841
Functional classRural Major 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
Deck0 FailedOut of service and beyond corrective action.
Superstructure0 FailedOut of service and beyond corrective action.
Substructure0 FailedOut of service and beyond corrective action.
Channel and channel protection7 GoodSome minor problems.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusClosed to all traffic
ScourFoundations stable; scour above top of footing
Structural evaluation0: Immediate repair necessary to put back in service
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating0 US tons
Inventory rating0 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length178 ft (54.3 m)
Longest span68 ft (20.7 m)
Deck width26 ft (8 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic370 (2022)
Projected traffic370 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 over N Skunk River Overflow built?

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

What condition is FM over N Skunk River Overflow 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 December 2023.

How much traffic does FM over N Skunk River Overflow carry?

About 370 vehicles per day (2022 count).

How long is FM over N Skunk River Overflow?

The structure is 178 ft (54.3 m) long with a longest span of 68 ft (20.7 m) and a deck 26 ft wide.

Who owns FM over N Skunk River Overflow?

It is owned by the County Highway Agency.