US Bridges

S 16 over Garden Coulee-Stockpass

Fair

Richland County, Montana · 1M S Savage · Structure no. P00020031+02501

Built
1975
50 years old
Condition
Fair
inspected January 2025
Type
Culvert
Steel
Length
23 ft
2 main spans
Daily traffic
2,313
2023 count
Owner
State
State Highway Agency

About this bridge

S 16 over Garden Coulee-Stockpass is a steel culvert carrying S 16 over Garden Coulee-Stockpass in Richland County, Montana. It was built in 1975, so it is 50 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 23 ft (7 m) long. If it were closed, the detour would be 65.9 mi (106 km).

Location

Open in Google Maps
CarriesS 16
CrossesGarden Coulee-Stockpass
Location1M S Savage
RouteState Highway 16
CountyRichland County
StateMontana
Coordinates47.44559, -104.35264
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadHS 20
Structure length23 ft (7 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 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 Garden Coulee-Stockpass built?

It was built in 1975, making it 50 years old in 2025.

What condition is S 16 over Garden Coulee-Stockpass 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 January 2025.

How much traffic does S 16 over Garden Coulee-Stockpass carry?

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

How long is S 16 over Garden Coulee-Stockpass?

The structure is 23 ft (7 m) long with a longest span of 10 ft (3 m).

Who owns S 16 over Garden Coulee-Stockpass?

It is owned by the State Highway Agency.