US Bridges

Seward Highway over Dowling RD Underxing

Good

Anchorage Municipality, Alaska · Mile Point 122.8 · Structure no. 1324

Built
2022
3 years old
Condition
Good
inspected June 2023
Type
Tee Beam
Prestressed Concrete
Length
146 ft
1 main span
Daily traffic
47,700
2020 count
Owner
State
State Highway Agency

About this bridge

Seward Highway over Dowling RD Underxing is a prestressed concrete tee beam carrying Seward Highway over Dowling RD Underxing in Anchorage Municipality, Alaska. It was built in 2022, so it is 3 years old, younger than the Alaska average of 35.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 9 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 47,700 vehicles a day, roughly 17% of them trucks, projected to reach 76,000 by 2039. The structure is 146 ft (44.5 m) long and 140 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesSeward Highway
CrossesDowling RD Underxing
LocationMile Point 122.8
RouteInterstate 0A31
StateAlaska
Coordinates61.16639, -149.85639
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck9 ExcellentNo problems noted.
Superstructure9 ExcellentNo problems noted.
Substructure9 ExcellentNo problems noted.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation9: Superior to present desirable criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating67.9 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 20
Structure length146 ft (44.5 m)
Longest span142 ft (43.3 m)
Deck width140 ft (42.8 m)
Roadway width136 ft (41.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic47,700 (2020)
Projected traffic76,000 by 2039
Trucks17%
Lanes on structure6
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Seward Highway over Dowling RD Underxing built?

It was built in 2022, making it 3 years old in 2025.

What condition is Seward Highway over Dowling RD Underxing in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in June 2023.

How much traffic does Seward Highway over Dowling RD Underxing carry?

About 47,700 vehicles per day (2020 count), of which roughly 17% are trucks.

How long is Seward Highway over Dowling RD Underxing?

The structure is 146 ft (44.5 m) long with a longest span of 142 ft (43.3 m) and a deck 140 ft wide.

Who owns Seward Highway over Dowling RD Underxing?

It is owned by the State Highway Agency.