US Bridges

Sterling Highway over Quartz Creek

Fair

Kenai Peninsula Borough, Alaska · Mile Point 4.0 · Structure no. 0676

Built
1965
60 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
163 ft
3 main spans
Daily traffic
2,900
2020 count
Owner
State
State Highway Agency

About this bridge

Sterling Highway over Quartz Creek is a steel stringer/multi-beam or girder carrying Sterling Highway over Quartz Creek 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 2,900 vehicles a day, roughly 11% of them trucks, projected to reach 3,670 by 2039. The structure is 163 ft (49.6 m) long and 39 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesSterling Highway
CrossesQuartz Creek
LocationMile Point 4.0
RouteInterstate 0A33
CountyKenai Peninsula Borough
StateAlaska
Coordinates60.52444, -149.65056
Functional classRural Principal Arterial - Interstate

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
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 evaluation6: Equal to 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 rating55.4 US tons
Inventory rating33.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length163 ft (49.6 m)
Longest span60 ft (18.3 m)
Deck width39 ft (11.9 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,900 (2020)
Projected traffic3,670 by 2039
Trucks11%
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 Sterling Highway over Quartz Creek built?

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

What condition is Sterling Highway over Quartz 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 August 2023.

How much traffic does Sterling Highway over Quartz Creek carry?

About 2,900 vehicles per day (2020 count), of which roughly 11% are trucks.

How long is Sterling Highway over Quartz Creek?

The structure is 163 ft (49.6 m) long with a longest span of 60 ft (18.3 m) and a deck 39 ft wide.

Who owns Sterling Highway over Quartz Creek?

It is owned by the State Highway Agency.