US Bridges

Blue Mountain Road over Jim Creek

Fair

Snohomish County, Washington · Navradsta Oso Wa · Structure no. 1WA0043

Built
1949
76 years old
Condition
Fair
inspected August 2024
Type
Box Beam or Girders - Single or Spread
Concrete Continuous
Length
99 ft
1 main span
Daily traffic
20
2018 count
Owner
Federal
Navy / Marines

About this bridge

Blue Mountain Road over Jim Creek is a concrete continuous box beam or girders - single or spread carrying Blue Mountain Road over Jim Creek in Snohomish County, Washington. It was built in 1949, so it is 76 years old, older than the Washington average of 49.8 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 20 vehicles a day, roughly 8% of them trucks, projected to reach 25 by 2043. The structure is 99 ft (30.2 m) long and 13 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesBlue Mountain Road
CrossesJim Creek
LocationNavradsta Oso Wa
RouteFederal Lands Road 0
CountySnohomish County
StateWashington
Coordinates48.21215, -121.93313
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionAugust 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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34.2 US tons
Inventory rating20.5 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans1 (+2 approach)
Design loadH 15
Structure length99 ft (30.2 m)
Longest span75 ft (22.9 m)
Deck width13 ft (4.1 m)
Roadway width12 ft (3.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (2018)
Projected traffic25 by 2043
Trucks8%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerNavy / Marines
Maintained byNavy / Marines
Historic statusNot eligible for the National Register of Historic Places
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$86,000 (2024 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was Blue Mountain Road over Jim Creek built?

It was built in 1949, making it 76 years old in 2025.

What condition is Blue Mountain Road over Jim 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 2024.

How much traffic does Blue Mountain Road over Jim Creek carry?

About 20 vehicles per day (2018 count), of which roughly 8% are trucks.

How long is Blue Mountain Road over Jim Creek?

The structure is 99 ft (30.2 m) long with a longest span of 75 ft (22.9 m) and a deck 13 ft wide.

Who owns Blue Mountain Road over Jim Creek?

It is owned by the Navy / Marines.