US Bridges

Fish Hatchery RD over Post Creek 075

Fair

Lake County, Montana · 4M N ST Ignatius · Structure no. L24363003+01001

Built
1920
105 years old
Condition
Fair
inspected March 2024
Type
Tee Beam
Concrete
Length
38 ft
1 main span
Daily traffic
100
2025 count
Owner
County
County Highway Agency

About this bridge

Fish Hatchery RD over Post Creek 075 is a concrete tee beam carrying Fish Hatchery RD over Post Creek 075 in Lake County, Montana. It was built in 1920, so it is 105 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 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 38 ft (11.7 m) long and 20 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesFish Hatchery RD
CrossesPost Creek 075
Location4M N ST Ignatius
RouteCounty Highway 24305
StateMontana
Coordinates47.39064, -114.1075
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
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 rating72.1 US tons
Inventory rating55.7 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckNot applicable
Main spans1
Design loadH 15
Structure length38 ft (11.7 m)
Longest span38 ft (11.5 m)
Deck width20 ft (6.2 m)
Roadway width18 ft (5.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2025)
Projected traffic100 by 2040
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 Fish Hatchery RD over Post Creek 075 built?

It was built in 1920, making it 105 years old in 2025.

What condition is Fish Hatchery RD over Post Creek 075 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 March 2024.

How much traffic does Fish Hatchery RD over Post Creek 075 carry?

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

How long is Fish Hatchery RD over Post Creek 075?

The structure is 38 ft (11.7 m) long with a longest span of 38 ft (11.5 m) and a deck 20 ft wide.

Who owns Fish Hatchery RD over Post Creek 075?

It is owned by the County Highway Agency.