US Bridges

Road over Illabot Creek

Fair

Skagit County, Washington · No Data Entered · Structure no. 060501000001497

Built
1968
57 years old
Condition
Fair
inspected October 2024
Type
Frame
Concrete Continuous
Length
105 ft
3 main spans
Daily traffic
20
1994 count
Owner
Federal
U.S. Forest Service

About this bridge

Road over Illabot Creek is a concrete continuous frame carrying Road over Illabot Creek in Skagit County, Washington. It was built in 1968, so it is 57 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 6 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, projected to reach 30 by 2045. The structure is 105 ft (32 m) long and 20 ft wide. If it were closed, the detour would be 98.2 mi (158 km).

Location

Open in Google Maps
CarriesRoad
CrossesIllabot Creek
LocationNo Data Entered
RouteFederal Lands Road 16000
CountySkagit County
StateWashington
Coordinates48.41217, -121.36294
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating51 US tons
Inventory rating35.1 US tons

Structure

Structure typeFrame
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length105 ft (32 m)
Longest span70 ft (21.3 m)
Deck width20 ft (6.1 m)
Roadway width17 ft (5.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (1994)
Projected traffic30 by 2045
Trucks—
Lanes on structure1
Traffic directionOne-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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Road over Illabot Creek built?

It was built in 1968, making it 57 years old in 2025.

What condition is Road over Illabot 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 October 2024.

How much traffic does Road over Illabot Creek carry?

About 20 vehicles per day (1994 count).

How long is Road over Illabot Creek?

The structure is 105 ft (32 m) long with a longest span of 70 ft (21.3 m) and a deck 20 ft wide.

Who owns Road over Illabot Creek?

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