US Bridges

Pumphouse RD over Big Hole River 009

FairPosted for load

Silver Bow County, Montana · 3M W Divide · Structure no. L47017000+01001

Built
1914
111 years old, rebuilt 2015
Condition
Fair
inspected July 2024
Type
Truss - Thru
Steel
Length
232 ft
1 main span
Daily traffic
100
2025 count
Owner
County
County Highway Agency

About this bridge

Pumphouse RD over Big Hole River 009 is a steel truss - thru carrying Pumphouse RD over Big Hole River 009 in Silver Bow County, Montana. It was built in 1914 and reconstructed in 2015, so it is 111 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 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 232 ft (70.7 m) long and 16 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesPumphouse RD
CrossesBig Hole River 009
Location3M W Divide
RouteCounty Highway 47017
CountySilver Bow County
StateMontana
Coordinates45.75972, -112.80165
Functional classRural Local

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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation2: Basically intolerable, requiring high priority of replacement
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 rating10 US tons
Inventory rating7.1 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1 (+1 approach)
Design loadUnknown
Structure length232 ft (70.7 m)
Longest span155 ft (47.2 m)
Deck width16 ft (4.8 m)
Roadway width13 ft (4.1 m)
Vertical clearance over deck15 ft (4.5 m)

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 closed1.9 mi (3 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$498,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Pumphouse RD over Big Hole River 009 built?

It was built in 1914, making it 111 years old in 2025. It was reconstructed in 2015.

What condition is Pumphouse RD over Big Hole River 009 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 July 2024.

How much traffic does Pumphouse RD over Big Hole River 009 carry?

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

How long is Pumphouse RD over Big Hole River 009?

The structure is 232 ft (70.7 m) long with a longest span of 155 ft (47.2 m) and a deck 16 ft wide.

Who owns Pumphouse RD over Big Hole River 009?

It is owned by the County Highway Agency.