US Bridges

Grand Island Road over Lambert Slough

Fair

Yamhill County, Oregon · 650 MI S Dayton · Structure no. 01496A029000327

Built
1964
61 years old
Condition
Fair
inspected September 2024
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
633 ft
3 main spans
Daily traffic
508
2020 count
Owner
County
County Highway Agency

About this bridge

Grand Island Road over Lambert Slough is a concrete continuous box beam or girders - multiple carrying Grand Island Road over Lambert Slough in Yamhill County, Oregon. It was built in 1964, so it is 61 years old, older than the Oregon average of 49.9 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 508 vehicles a day, roughly 20% of them trucks, projected to reach 548 by 2025. The structure is 633 ft (192.9 m) long and 32 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesGrand Island Road
CrossesLambert Slough
Location650 MI S Dayton
RouteCounty Highway A0697
CountyYamhill County
StateOregon
Coordinates45.12773, -123.05204
Functional classRural Major Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating31.4 US tons
Inventory rating24.3 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3 (+5 approach)
Design loadHS 20
Structure length633 ft (192.9 m)
Longest span120 ft (36.6 m)
Deck width32 ft (9.8 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic508 (2020)
Projected traffic548 by 2025
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Grand Island Road over Lambert Slough built?

It was built in 1964, making it 61 years old in 2025.

What condition is Grand Island Road over Lambert Slough 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 September 2024.

How much traffic does Grand Island Road over Lambert Slough carry?

About 508 vehicles per day (2020 count), of which roughly 20% are trucks.

How long is Grand Island Road over Lambert Slough?

The structure is 633 ft (192.9 m) long with a longest span of 120 ft (36.6 m) and a deck 32 ft wide.

Who owns Grand Island Road over Lambert Slough?

It is owned by the County Highway Agency.