US Bridges

US 93 over Mission Creek

Fair

Lake County, Montana · ST Ignatius · Structure no. P00005032+04001

Built
2006
19 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
133 ft
1 main span
Daily traffic
7,746
2023 count
Owner
State
State Highway Agency

About this bridge

US 93 over Mission Creek is a prestressed concrete stringer/multi-beam or girder carrying US 93 over Mission Creek in Lake County, Montana. It was built in 2006, so it is 19 years old, younger 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 7,746 vehicles a day, roughly 5% of them trucks, projected to reach 8,133 by 2043. The structure is 133 ft (40.5 m) long and 54 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

CarriesUS 93
CrossesMission Creek
LocationST Ignatius
RouteU.S. Route 93
StateMontana
Coordinates47.31958, -114.10572
Functional classRural Principal Arterial - Other

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.
Superstructure8 Very GoodNo problems noted.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionAugust 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 geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating68 US tons
Inventory rating42 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length133 ft (40.5 m)
Longest span133 ft (40.5 m)
Deck width54 ft (16.6 m)
Roadway width52 ft (15.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,746 (2023)
Projected traffic8,133 by 2043
Trucks5%
Lanes on structure3
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 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 US 93 over Mission Creek built?

It was built in 2006, making it 19 years old in 2025.

What condition is US 93 over Mission Creek 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 August 2023.

How much traffic does US 93 over Mission Creek carry?

About 7,746 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is US 93 over Mission Creek?

The structure is 133 ft (40.5 m) long with a longest span of 133 ft (40.5 m) and a deck 54 ft wide.

Who owns US 93 over Mission Creek?

It is owned by the State Highway Agency.