US Bridges

8400000 over Perm

Good

Ketchikan Gateway Borough, Alaska · Shoal Cove · Structure no. 100520000001134

Built
1985
40 years old
Condition
Good
inspected June 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
61 ft
1 main span
Daily traffic
5
2006 count
Owner
Federal
U.S. Forest Service

About this bridge

8400000 over Perm is a wood or timber stringer/multi-beam or girder carrying 8400000 over Perm in Ketchikan Gateway Borough, Alaska. It was built in 1985, so it is 40 years old, older 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 5 vehicles a day, projected to reach 10 by 2013. The structure is 61 ft (18.6 m) long and 17 ft wide. If it were closed, the detour would be 98.2 mi (158 km).

Location

Open in Google Maps
Carries8400000
CrossesPerm
LocationShoal Cove
RouteFederal Lands Road 84000
CountyKetchikan Gateway Borough
StateAlaska
Coordinates55.48803, -131.27638
Functional classRural Local

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.3 US tons
Inventory rating54.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadOther
Structure length61 ft (18.6 m)
Longest span56 ft (17.1 m)
Deck width17 ft (5.2 m)
Roadway width15 ft (4.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5 (2006)
Projected traffic10 by 2013
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.2 mi (158 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerU.S. Forest Service
Maintained byU.S. Forest Service
Historic statusHistorical significance not determinable at this time
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$162,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 8400000 over Perm built?

It was built in 1985, making it 40 years old in 2025.

What condition is 8400000 over Perm 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 2024.

How much traffic does 8400000 over Perm carry?

About 5 vehicles per day (2006 count).

How long is 8400000 over Perm?

The structure is 61 ft (18.6 m) long with a longest span of 56 ft (17.1 m) and a deck 17 ft wide.

Who owns 8400000 over Perm?

It is owned by the U.S. Forest Service.