US Bridges

IRR - US 2 over Stillwater River

Fair

Flathead County, Montana · 1M NE Kalispell · Structure no. P00001122+03341

Built
1966
59 years old, rebuilt 1995
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
184 ft
2 main spans
Daily traffic
13,680
2023 count
Owner
State
State Highway Agency

About this bridge

IRR - US 2 over Stillwater River is a prestressed concrete stringer/multi-beam or girder carrying IRR - US 2 over Stillwater River in Flathead County, Montana. It was built in 1966 and reconstructed in 1995, so it is 59 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 13,680 vehicles a day, roughly 1% of them trucks, projected to reach 14,364 by 2043. The structure is 184 ft (56.1 m) long and 33 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesIRR - US 2
CrossesStillwater River
Location1M NE Kalispell
RouteU.S. Route 2
CountyFlathead County
StateMontana
Coordinates48.21083, -114.28702
Functional classUrban Other Principal Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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 inspectionOctober 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 rating50 US tons
Inventory rating39 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length184 ft (56.1 m)
Longest span91 ft (27.7 m)
Deck width33 ft (10.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic13,680 (2023)
Projected traffic14,364 by 2043
Trucks1%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 IRR - US 2 over Stillwater River built?

It was built in 1966, making it 59 years old in 2025. It was reconstructed in 1995.

What condition is IRR - US 2 over Stillwater River 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 October 2023.

How much traffic does IRR - US 2 over Stillwater River carry?

About 13,680 vehicles per day (2023 count), of which roughly 1% are trucks.

How long is IRR - US 2 over Stillwater River?

The structure is 184 ft (56.1 m) long with a longest span of 91 ft (27.7 m) and a deck 33 ft wide.

Who owns IRR - US 2 over Stillwater River?

It is owned by the State Highway Agency.