US Bridges

N31 over Armbrust Creek

Good

Sarpy County, Nebraska · 6S Gretna · Structure no. S031 00805

Built
1984
41 years old
Condition
Good
inspected January 2022
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
153 ft
3 main spans
Daily traffic
1,625
2018 count
Owner
State
State Highway Agency

About this bridge

N31 over Armbrust Creek is a steel continuous stringer/multi-beam or girder carrying N31 over Armbrust Creek in Sarpy County, Nebraska. It was built in 1984, so it is 41 years old, younger than the Nebraska average of 47.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1,625 vehicles a day, roughly 10% of them trucks, projected to reach 2,600 by 2038. The structure is 153 ft (46.6 m) long and 34 ft wide. If it were closed, the detour would be 31.1 mi (50 km).

Location

Open in Google Maps
CarriesN31
CrossesArmbrust Creek
Location6S Gretna
RouteState Highway 31
CountySarpy County
StateNebraska
Coordinates41.0498, -96.2531
Functional classRural Minor Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJanuary 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
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 rating87.1 US tons
Inventory rating51.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length153 ft (46.6 m)
Longest span59 ft (18 m)
Deck width34 ft (10.5 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,625 (2018)
Projected traffic2,600 by 2038
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed31.1 mi (50 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was N31 over Armbrust Creek built?

It was built in 1984, making it 41 years old in 2025.

What condition is N31 over Armbrust Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in January 2022.

How much traffic does N31 over Armbrust Creek carry?

About 1,625 vehicles per day (2018 count), of which roughly 10% are trucks.

How long is N31 over Armbrust Creek?

The structure is 153 ft (46.6 m) long with a longest span of 59 ft (18 m) and a deck 34 ft wide.

Who owns N31 over Armbrust Creek?

It is owned by the State Highway Agency.