US Bridges

S 16 over Dunlap Creek

Fair

Richland County, Montana · 1M N Savage · Structure no. P00020032+03991

Built
1974
51 years old
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
124 ft
3 main spans
Daily traffic
2,313
2023 count
Owner
State
State Highway Agency

About this bridge

S 16 over Dunlap Creek is a prestressed concrete stringer/multi-beam or girder carrying S 16 over Dunlap Creek in Richland County, Montana. It was built in 1974, so it is 51 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 6 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 2,313 vehicles a day, roughly 13% of them trucks, projected to reach 2,440 by 2043. The structure is 124 ft (37.7 m) long and 46 ft wide. If it were closed, the detour would be 65.9 mi (106 km).

Location

Open in Google Maps
CarriesS 16
CrossesDunlap Creek
Location1M N Savage
RouteState Highway 16
CountyRichland County
StateMontana
Coordinates47.46131, -104.34278
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46 US tons
Inventory rating33 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length124 ft (37.7 m)
Longest span41 ft (12.5 m)
Deck width46 ft (14.1 m)
Roadway width44 ft (13.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,313 (2023)
Projected traffic2,440 by 2043
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed65.9 mi (106 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 S 16 over Dunlap Creek built?

It was built in 1974, making it 51 years old in 2025.

What condition is S 16 over Dunlap 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 May 2024.

How much traffic does S 16 over Dunlap Creek carry?

About 2,313 vehicles per day (2023 count), of which roughly 13% are trucks.

How long is S 16 over Dunlap Creek?

The structure is 124 ft (37.7 m) long with a longest span of 41 ft (12.5 m) and a deck 46 ft wide.

Who owns S 16 over Dunlap Creek?

It is owned by the State Highway Agency.