US Bridges

Trail Creek RD over Mizpah Creek 086

Fair

Custer County, Montana · 27M SE Miles City · Structure no. L09301016+02001

Built
1981
44 years old
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
90 ft
2 main spans
Daily traffic
56
2023 count
Owner
County
County Highway Agency

About this bridge

Trail Creek RD over Mizpah Creek 086 is a steel stringer/multi-beam or girder carrying Trail Creek RD over Mizpah Creek 086 in Custer County, Montana. It was built in 1981, so it is 44 years old, younger than the Montana average of 47 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 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 56 vehicles a day, roughly 3% of them trucks, projected to reach 59 by 2043. The structure is 90 ft (27.4 m) long and 24 ft wide. If it were closed, the detour would be 44.7 mi (72 km).

Location

Open in Google Maps
CarriesTrail Creek RD
CrossesMizpah Creek 086
Location27M SE Miles City
RouteCounty Highway 9301
CountyCuster County
StateMontana
Coordinates46.26088, -105.29313
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to 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 alignment6: Equal to present minimum criteria
Operating rating68 US tons
Inventory rating52 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length90 ft (27.4 m)
Longest span45 ft (13.7 m)
Deck width24 ft (7.3 m)
Roadway width22 ft (6.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic56 (2023)
Projected traffic59 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed44.7 mi (72 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Trail Creek RD over Mizpah Creek 086 built?

It was built in 1981, making it 44 years old in 2025.

What condition is Trail Creek RD over Mizpah Creek 086 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 2023.

How much traffic does Trail Creek RD over Mizpah Creek 086 carry?

About 56 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Trail Creek RD over Mizpah Creek 086?

The structure is 90 ft (27.4 m) long with a longest span of 45 ft (13.7 m) and a deck 24 ft wide.

Who owns Trail Creek RD over Mizpah Creek 086?

It is owned by the County Highway Agency.