US Bridges

N12 over Coon Creek

Fair

Keya Paha County, Nebraska · 2SW Brocksburg · Structure no. S012 07966

Built
1949
76 years old
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
36 ft
1 main span
Daily traffic
345
2018 count
Owner
State
State Highway Agency

About this bridge

N12 over Coon Creek is a steel stringer/multi-beam or girder carrying N12 over Coon Creek in Keya Paha County, Nebraska. It was built in 1949, so it is 76 years old, older than the Nebraska average of 47.1 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 345 vehicles a day, roughly 13% of them trucks, projected to reach 483 by 2038. The structure is 36 ft (11 m) long and 29 ft wide. If it were closed, the detour would be 62.1 mi (100 km).

Location

Open in Google Maps
CarriesN12
CrossesCoon Creek
Location2SW Brocksburg
RouteState Highway 12
CountyKeya Paha County
StateNebraska
Coordinates42.9223, -99.353
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.1 US tons
Inventory rating26.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length36 ft (11 m)
Longest span35 ft (10.7 m)
Deck width29 ft (8.7 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic345 (2018)
Projected traffic483 by 2038
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed62.1 mi (100 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was N12 over Coon Creek built?

It was built in 1949, making it 76 years old in 2025.

What condition is N12 over Coon 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 March 2023.

How much traffic does N12 over Coon Creek carry?

About 345 vehicles per day (2018 count), of which roughly 13% are trucks.

How long is N12 over Coon Creek?

The structure is 36 ft (11 m) long with a longest span of 35 ft (10.7 m) and a deck 29 ft wide.

Who owns N12 over Coon Creek?

It is owned by the State Highway Agency.