US Bridges

Denali Highway over Tangle River

Fair

County 066, Alaska · Mile Point 21.4 · Structure no. 0683

Built
1954
71 years old
Condition
Fair
inspected July 2023
Type
Truss - Thru
Steel
Length
103 ft
1 main span
Daily traffic
140
2020 count
Owner
State
State Highway Agency

About this bridge

Denali Highway over Tangle River is a steel truss - thru carrying Denali Highway over Tangle River in County 066, Alaska. It was built in 1954, so it is 71 years old, older than the Alaska average of 35.9 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 140 vehicles a day, roughly 21% of them trucks, projected to reach 250 by 2039. The structure is 103 ft (31.4 m) long and 20 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

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CarriesDenali Highway
CrossesTangle River
LocationMile Point 21.4
RouteState Highway 750
CountyCounty 066
StateAlaska
Coordinates63.0461, -146.0179
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 protection8 Very GoodNo problems noted.
Last inspectionJuly 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 geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.8 US tons
Inventory rating28.8 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckWood or timber
Main spans1
Design loadH 20
Structure length103 ft (31.4 m)
Longest span100 ft (30.5 m)
Deck width20 ft (6.1 m)
Roadway width19 ft (5.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic140 (2020)
Projected traffic250 by 2039
Trucks21%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 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 Denali Highway over Tangle River built?

It was built in 1954, making it 71 years old in 2025.

What condition is Denali Highway over Tangle River 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 July 2023.

How much traffic does Denali Highway over Tangle River carry?

About 140 vehicles per day (2020 count), of which roughly 21% are trucks.

How long is Denali Highway over Tangle River?

The structure is 103 ft (31.4 m) long with a longest span of 100 ft (30.5 m) and a deck 20 ft wide.

Who owns Denali Highway over Tangle River?

It is owned by the State Highway Agency.