US Bridges

Rock Creek Lake RD over Rock Creek 079

Good

Powell County, Montana · 8M NW Deer Lodge · Structure no. L39006008+01001

Built
2009
16 years old
Condition
Good
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
50 ft
1 main span
Daily traffic
100
2025 count
Owner
County
County Highway Agency

About this bridge

Rock Creek Lake RD over Rock Creek 079 is a steel stringer/multi-beam or girder carrying Rock Creek Lake RD over Rock Creek 079 in Powell County, Montana. It was built in 2009, so it is 16 years old, younger 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 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 50 ft (15.2 m) long and 16 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

CarriesRock Creek Lake RD
CrossesRock Creek 079
Location8M NW Deer Lodge
RouteCounty Highway 6
StateMontana
Coordinates46.42847, -112.93944
Functional classRural Local

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 protection8 Very GoodNo problems noted.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
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 alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating65.4 US tons
Inventory rating50.4 US tons

Structure

MaterialSteel
DeckCorrugated steel
Main spans1
Design loadOther
Structure length50 ft (15.2 m)
Longest span49 ft (14.9 m)
Deck width16 ft (5 m)
Roadway width14 ft (4.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2025)
Projected traffic100 by 2040
Trucks3%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 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 Rock Creek Lake RD over Rock Creek 079 built?

It was built in 2009, making it 16 years old in 2025.

What condition is Rock Creek Lake RD over Rock Creek 079 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 July 2023.

How much traffic does Rock Creek Lake RD over Rock Creek 079 carry?

About 100 vehicles per day (2025 count), of which roughly 3% are trucks.

How long is Rock Creek Lake RD over Rock Creek 079?

The structure is 50 ft (15.2 m) long with a longest span of 49 ft (14.9 m) and a deck 16 ft wide.

Who owns Rock Creek Lake RD over Rock Creek 079?

It is owned by the County Highway Agency.