US Bridges

So M 16 over Mosquito Creek

FairPosted for load

Shelby County, Iowa · 0000 · Structure no. 000000000004400

Built
1963
62 years old
Condition
Fair
inspected April 2024
Type
Slab
Concrete Continuous
Length
103 ft
3 main spans
Daily traffic
349
2022 count
Owner
County
County Highway Agency

About this bridge

So M 16 over Mosquito Creek is a concrete continuous slab carrying So M 16 over Mosquito Creek in Shelby County, Iowa. It was built in 1963, so it is 62 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. Its operating status is: posted for load restriction.

It carries about 349 vehicles a day, roughly 10% of them trucks, projected to reach 349 by 2044. The structure is 103 ft (31.4 m) long and 26 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesSo M 16
CrossesMosquito Creek
Location0000
RouteCity Street 0
CountyShelby County
StateIowa
Coordinates41.77201, -95.4207
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being 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 rating40.7 US tons
Inventory rating24.7 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length103 ft (31.4 m)
Longest span39 ft (11.9 m)
Deck width26 ft (8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic349 (2022)
Projected traffic349 by 2044
Trucks10%
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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was So M 16 over Mosquito Creek built?

It was built in 1963, making it 62 years old in 2025.

What condition is So M 16 over Mosquito Creek 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 April 2024.

How much traffic does So M 16 over Mosquito Creek carry?

About 349 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is So M 16 over Mosquito Creek?

The structure is 103 ft (31.4 m) long with a longest span of 39 ft (11.9 m) and a deck 26 ft wide.

Who owns So M 16 over Mosquito Creek?

It is owned by the County Highway Agency.