US Bridges

S 511 over N Fork Whitetail Creek

Fair

Daniels County, Montana · 1M N Whitetail · Structure no. S00511007+00001

Built
1934
91 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
39 ft
2 main spans
Daily traffic
24
2023 count
Owner
State
State Highway Agency

About this bridge

S 511 over N Fork Whitetail Creek is a wood or timber stringer/multi-beam or girder carrying S 511 over N Fork Whitetail Creek in Daniels County, Montana. It was built in 1934, so it is 91 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 24 vehicles a day, projected to reach 25 by 2043. The structure is 39 ft (11.9 m) long and 22 ft wide. If it were closed, the detour would be 62.8 mi (101 km).

Location

Open in Google Maps
CarriesS 511
CrossesN Fork Whitetail Creek
Location1M N Whitetail
RouteState Highway 511
CountyDaniels County
StateMontana
Coordinates48.9016, -105.16404
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
Deck7 GoodSome minor problems.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
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 adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61 US tons
Inventory rating43 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans2
Design loadH 15
Structure length39 ft (11.9 m)
Longest span19 ft (5.8 m)
Deck width22 ft (6.7 m)
Roadway width21 ft (6.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic24 (2023)
Projected traffic25 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed62.8 mi (101 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 S 511 over N Fork Whitetail Creek built?

It was built in 1934, making it 91 years old in 2025.

What condition is S 511 over N Fork Whitetail 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 October 2023.

How much traffic does S 511 over N Fork Whitetail Creek carry?

About 24 vehicles per day (2023 count).

How long is S 511 over N Fork Whitetail Creek?

The structure is 39 ft (11.9 m) long with a longest span of 19 ft (5.8 m) and a deck 22 ft wide.

Who owns S 511 over N Fork Whitetail Creek?

It is owned by the State Highway Agency.