US Bridges

Old US 10 over Big Ditch 010

Fair

Stillwater County, Montana · Park City · Structure no. L48241000+01001

Built
1928
97 years old
Condition
Fair
inspected November 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
35 ft
1 main span
Daily traffic
828
2023 count
Owner
State
State Highway Agency

About this bridge

Old US 10 over Big Ditch 010 is a steel stringer/multi-beam or girder carrying Old US 10 over Big Ditch 010 in Stillwater County, Montana. It was built in 1928, so it is 97 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 828 vehicles a day, roughly 1% of them trucks, projected to reach 911 by 2043. The structure is 35 ft (10.7 m) long and 29 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

Location

Open in Google Maps
CarriesOld US 10
CrossesBig Ditch 010
LocationPark City
RouteState Highway 81015
CountyStillwater County
StateMontana
Coordinates45.63969, -108.91558
Functional classRural Major Collector

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 protection7 GoodSome minor problems.
Last inspectionNovember 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 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 rating43 US tons
Inventory rating26 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length35 ft (10.7 m)
Longest span33 ft (10.1 m)
Deck width29 ft (8.9 m)
Roadway width27 ft (8.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic828 (2023)
Projected traffic911 by 2043
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.3 mi (23 km)
TollOn a free road
National Highway SystemNo

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 Old US 10 over Big Ditch 010 built?

It was built in 1928, making it 97 years old in 2025.

What condition is Old US 10 over Big Ditch 010 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 November 2023.

How much traffic does Old US 10 over Big Ditch 010 carry?

About 828 vehicles per day (2023 count), of which roughly 1% are trucks.

How long is Old US 10 over Big Ditch 010?

The structure is 35 ft (10.7 m) long with a longest span of 33 ft (10.1 m) and a deck 29 ft wide.

Who owns Old US 10 over Big Ditch 010?

It is owned by the State Highway Agency.