US Bridges

FM over Sny Magill

Fair

Clayton County, Iowa · 094032206 · Structure no. 000000000120271

Built
1980
45 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
158 ft
3 main spans
Daily traffic
953
2022 count
Owner
County
County Highway Agency

About this bridge

FM over Sny Magill is a prestressed concrete stringer/multi-beam or girder carrying FM over Sny Magill in Clayton County, Iowa. It was built in 1980, so it is 45 years old, younger 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 953 vehicles a day, roughly 12% of them trucks, projected to reach 953 by 2044. The structure is 158 ft (48.2 m) long and 39 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesFM
CrossesSny Magill
Location094032206
RouteCounty Highway 0
CountyClayton County
StateIowa
Coordinates42.93845, -91.17702
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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 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 rating56.4 US tons
Inventory rating43.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length158 ft (48.2 m)
Longest span61 ft (18.6 m)
Deck width39 ft (11.9 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic953 (2022)
Projected traffic953 by 2044
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 Sny Magill built?

It was built in 1980, making it 45 years old in 2025.

What condition is FM over Sny Magill 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 October 2024.

How much traffic does FM over Sny Magill carry?

About 953 vehicles per day (2022 count), of which roughly 12% are trucks.

How long is FM over Sny Magill?

The structure is 158 ft (48.2 m) long with a longest span of 61 ft (18.6 m) and a deck 39 ft wide.

Who owns FM over Sny Magill?

It is owned by the County Highway Agency.