US Bridges

Porcupine Road over Porcupine Creek

Fair

Haines Borough, Alaska · Mile Point 8.3 · Structure no. 1635

Built
2012
13 years old
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
80 ft
1 main span
Daily traffic
10
2018 count
Owner
State
State Park, Forest, or Reservation Agency

About this bridge

Porcupine Road over Porcupine Creek is a steel stringer/multi-beam or girder carrying Porcupine Road over Porcupine Creek in Haines Borough, Alaska. It was built in 2012, so it is 13 years old, younger 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 10 vehicles a day, roughly 1% of them trucks, projected to reach 12 by 2035. The structure is 80 ft (24.4 m) long and 17 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesPorcupine Road
CrossesPorcupine Creek
LocationMile Point 8.3
RouteState Lands Road 0
CountyHaines Borough
StateAlaska
Coordinates59.42048, -136.22274
Functional classRural Minor 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
Deck8 Very GoodNo problems noted.
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 inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating34.8 US tons
Inventory rating25.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1
Design loadUnknown
Structure length80 ft (24.4 m)
Longest span77 ft (23.5 m)
Deck width17 ft (5.3 m)
Roadway width15 ft (4.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (2018)
Projected traffic12 by 2035
Trucks1%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Park, Forest, or Reservation Agency
Maintained byState Park, Forest, or Reservation 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 Porcupine Road over Porcupine Creek built?

It was built in 2012, making it 13 years old in 2025.

What condition is Porcupine Road over Porcupine 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 May 2024.

How much traffic does Porcupine Road over Porcupine Creek carry?

About 10 vehicles per day (2018 count), of which roughly 1% are trucks.

How long is Porcupine Road over Porcupine Creek?

The structure is 80 ft (24.4 m) long with a longest span of 77 ft (23.5 m) and a deck 17 ft wide.

Who owns Porcupine Road over Porcupine Creek?

It is owned by the State Park, Forest, or Reservation Agency.