Structure 2349 · Ketchikan Gateway County, AK

Bostwick Lake Road over Bostwick No. 4

Carries Bostwick Lake Road over Bostwick No. 4, Mile Point 2.7.

Overall conditionFair

Set by its lowest-rated component: Deck and Superstructure and Substructure at 5 of 9.

How ratings work
Decksets the rating5/9 · Fair
Superstructuresets the rating5/9 · Fair
Substructuresets the rating5/9 · Fair
Channelnot part of overall7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
CAR · 15 FT31 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 5/9Superstructure 5/9Substructure 5/9

31 ft end to end. Lengths and the car on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built200620 years old
Length30.8 ft9.4 m
Daily traffic10counted 2018
Last inspectedJune 2023every 24 months

Location

StateAlaska
CountyKetchikan Gateway
LocationMile Point 2.7
CarriesBostwick Lake Road
CrossesBostwick No. 4
Coordinates55.32117, -131.74926

Physical Characteristics

MaterialWood or Timber
DesignStringer/Multi-beam
Total Length30.8 ft (9.4 m)
Max Span30.8 ft (9.4 m)
Deck Width24.6 ft (7.5 m)
Deck Area70.5 sq m
Main Spans1
Year Built2006

Traffic

Avg Daily Traffic10 (2018)
Truck Traffic70%
Lanes On Bridge1

Inspection & Ownership

Last InspectionJune 2023
Inspection FrequencyEvery 24 months
OwnerState Park/Forest Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical3 — Scour critical
Structure Number2349

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

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