US Bridges

Mission Dam Road over Mission Creek

GoodPosted for load

Lake County, Montana · 2M E ST Ignatius · Structure no. 000000202103308

Built
2021
4 years old
Condition
Good
inspected December 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

Mission Dam Road over Mission Creek is a steel stringer/multi-beam or girder carrying Mission Dam Road over Mission Creek in Lake County, Montana. It was built in 2021, so it is 4 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. 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 50 ft (15.2 m) long and 21 ft wide. If it were closed, the detour would be 4.3 mi (7 km).

Location

Open in Google Maps
CarriesMission Dam Road
CrossesMission Creek
Location2M E ST Ignatius
RouteCounty Highway 24467
CountyLake County
StateMontana
Coordinates47.31228, -114.08458
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 inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to 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 alignment8: Equal to present desirable criteria
Operating rating37 US tons
Inventory rating29 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckCorrugated steel
Main spans1
Design loadUnknown
Structure length50 ft (15.2 m)
Longest span49 ft (14.9 m)
Deck width21 ft (6.4 m)
Roadway width20 ft (6.1 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 and pedestrian
CrossesWaterway
Detour if closed4.3 mi (7 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 Mission Dam Road over Mission Creek built?

It was built in 2021, making it 4 years old in 2025.

What condition is Mission Dam Road over Mission Creek 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 December 2023.

How much traffic does Mission Dam Road over Mission Creek carry?

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

How long is Mission Dam Road over Mission Creek?

The structure is 50 ft (15.2 m) long with a longest span of 49 ft (14.9 m) and a deck 21 ft wide.

Who owns Mission Dam Road over Mission Creek?

It is owned by the County Highway Agency.