US Bridges

County Road 540 over Lower Seven Mile CR 008

Good

Dawson County, Montana · 18M SE Bloomfield · Structure no. L11403005+03001

Built
1969
56 years old
Condition
Good
inspected October 2023
Type
Channel Beam
Prestressed Concrete
Length
78 ft
1 main span
Daily traffic
26
2023 count
Owner
County
County Highway Agency

About this bridge

County Road 540 over Lower Seven Mile CR 008 is a prestressed concrete channel beam carrying County Road 540 over Lower Seven Mile CR 008 in Dawson County, Montana. It was built in 1969, so it is 56 years old, older than the Montana average of 47 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 26 vehicles a day, roughly 3% of them trucks, projected to reach 27 by 2043. The structure is 78 ft (23.9 m) long and 20 ft wide. If it were closed, the detour would be 16.8 mi (27 km).

CarriesCounty Road 540
CrossesLower Seven Mile CR 008
Location18M SE Bloomfield
RouteCounty Highway 11403
StateMontana
Coordinates47.2654, -104.74764
Functional classRural Minor Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating53.9 US tons
Inventory rating36 US tons

Structure

Structure typeChannel Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length78 ft (23.9 m)
Longest span75 ft (22.9 m)
Deck width20 ft (6.1 m)
Roadway width19 ft (5.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic26 (2023)
Projected traffic27 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed16.8 mi (27 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 County Road 540 over Lower Seven Mile CR 008 built?

It was built in 1969, making it 56 years old in 2025.

What condition is County Road 540 over Lower Seven Mile CR 008 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 October 2023.

How much traffic does County Road 540 over Lower Seven Mile CR 008 carry?

About 26 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is County Road 540 over Lower Seven Mile CR 008?

The structure is 78 ft (23.9 m) long with a longest span of 75 ft (22.9 m) and a deck 20 ft wide.

Who owns County Road 540 over Lower Seven Mile CR 008?

It is owned by the County Highway Agency.