US Bridges

Mullan Gulch RD over Rock Creek 013

Fair

Mineral County, Montana · Henderson · Structure no. L31179000+05001

Built
1931
94 years old
Condition
Fair
inspected November 2023
Type
Tee Beam
Concrete
Length
35 ft
1 main span
Daily traffic
150
2023 count
Owner
County
County Highway Agency

About this bridge

Mullan Gulch RD over Rock Creek 013 is a concrete tee beam carrying Mullan Gulch RD over Rock Creek 013 in Mineral County, Montana. It was built in 1931, so it is 94 years old, older 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 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 150 vehicles a day, projected to reach 158 by 2043. The structure is 35 ft (10.7 m) long and 25 ft wide. If it were closed, the detour would be 24.9 mi (40 km).

Location

Open in Google Maps
CarriesMullan Gulch RD
CrossesRock Creek 013
LocationHenderson
RouteCounty Highway 31179
CountyMineral County
StateMontana
Coordinates47.35669, -115.28869
Functional classRural Minor 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
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 rating35.1 US tons
Inventory rating27 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckNot applicable
Main spans1
Design loadH 15
Structure length35 ft (10.7 m)
Longest span34 ft (10.4 m)
Deck width25 ft (7.7 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic150 (2023)
Projected traffic158 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed24.9 mi (40 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 Mullan Gulch RD over Rock Creek 013 built?

It was built in 1931, making it 94 years old in 2025.

What condition is Mullan Gulch RD over Rock Creek 013 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 November 2023.

How much traffic does Mullan Gulch RD over Rock Creek 013 carry?

About 150 vehicles per day (2023 count).

How long is Mullan Gulch RD over Rock Creek 013?

The structure is 35 ft (10.7 m) long with a longest span of 34 ft (10.4 m) and a deck 25 ft wide.

Who owns Mullan Gulch RD over Rock Creek 013?

It is owned by the County Highway Agency.