US Bridges

8340000 over Mod

Fair

Ketchikan Gateway Borough, Alaska · Shelter · Structure no. 100520000001147

Built
1990
35 years old
Condition
Fair
inspected June 2024
Type
Box Beam or Girders - Multiple
Steel
Length
70 ft
1 main span
Daily traffic
—
2006 count
Owner
Federal
U.S. Forest Service

About this bridge

8340000 over Mod is a steel box beam or girders - multiple carrying 8340000 over Mod in Ketchikan Gateway Borough, Alaska. It was built in 1990, so it is 35 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.

No traffic count is recorded. The structure is 70 ft (21.3 m) long and 18 ft wide. If it were closed, the detour would be 98.2 mi (158 km).

Carries8340000
CrossesMod
LocationShelter
RouteFederal Lands Road 84440
StateAlaska
Coordinates55.4408, -131.3485
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
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 inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating31.1 US tons
Inventory rating23.9 US tons

Structure

MaterialSteel
DeckWood or timber
Main spans1
Design loadOther
Structure length70 ft (21.3 m)
Longest span69 ft (20.9 m)
Deck width18 ft (5.5 m)
Roadway width16 ft (4.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic—
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$182,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 8340000 over Mod built?

It was built in 1990, making it 35 years old in 2025.

What condition is 8340000 over Mod 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 June 2024.

How much traffic does 8340000 over Mod carry?

No traffic count is recorded for this structure.

How long is 8340000 over Mod?

The structure is 70 ft (21.3 m) long with a longest span of 69 ft (20.9 m) and a deck 18 ft wide.

Who owns 8340000 over Mod?

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