US Bridges

Seward Highway over Snow River West Channel

Fair

Kenai Peninsula Borough, Alaska · Mile Point 17.0 · Structure no. 0603

Built
1965
60 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
189 ft
2 main spans
Daily traffic
1,700
2020 count
Owner
State
State Highway Agency

About this bridge

Seward Highway over Snow River West Channel is a prestressed concrete stringer/multi-beam or girder carrying Seward Highway over Snow River West Channel in Kenai Peninsula Borough, Alaska. It was built in 1965, so it is 60 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 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 1,700 vehicles a day, roughly 6% of them trucks, projected to reach 2,210 by 2039. The structure is 189 ft (57.5 m) long and 34 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

CarriesSeward Highway
CrossesSnow River West Channel
LocationMile Point 17.0
RouteState Highway 31
StateAlaska
Coordinates60.32611, -149.35972
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 protection8 Very GoodNo problems noted.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating76.4 US tons
Inventory rating35.2 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadH 20
Structure length189 ft (57.5 m)
Longest span90 ft (27.4 m)
Deck width34 ft (10.4 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,700 (2020)
Projected traffic2,210 by 2039
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Seward Highway over Snow River West Channel built?

It was built in 1965, making it 60 years old in 2025.

What condition is Seward Highway over Snow River West Channel 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 August 2023.

How much traffic does Seward Highway over Snow River West Channel carry?

About 1,700 vehicles per day (2020 count), of which roughly 6% are trucks.

How long is Seward Highway over Snow River West Channel?

The structure is 189 ft (57.5 m) long with a longest span of 90 ft (27.4 m) and a deck 34 ft wide.

Who owns Seward Highway over Snow River West Channel?

It is owned by the State Highway Agency.