US Bridges

Nemah Valley Road over Nemah River

Fair

Pacific County, Washington · 8.1 N JCT 4 & 101 · Structure no. 083180000000000

Built
1981
44 years old
Condition
Fair
inspected June 2024
Type
Slab
Prestressed Concrete
Length
73 ft
3 main spans
Daily traffic
74
2023 count
Owner
County
County Highway Agency

About this bridge

Nemah Valley Road over Nemah River is a prestressed concrete slab carrying Nemah Valley Road over Nemah River in Pacific County, Washington. It was built in 1981, so it is 44 years old, younger 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 74 vehicles a day, projected to reach 130 by 2043. The structure is 73 ft (22.1 m) long and 28 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesNemah Valley Road
CrossesNemah River
Location8.1 N JCT 4 & 101
RouteCounty Highway 40420
CountyPacific County
StateWashington
Coordinates46.51356, -123.86267
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating41 US tons
Inventory rating30 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckOther
Main spans3
Design loadHS 20
Structure length73 ft (22.1 m)
Longest span24 ft (7.4 m)
Deck width28 ft (8.5 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic74 (2023)
Projected traffic130 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$964,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nemah Valley Road over Nemah River built?

It was built in 1981, making it 44 years old in 2025.

What condition is Nemah Valley Road over Nemah River 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 Nemah Valley Road over Nemah River carry?

About 74 vehicles per day (2023 count).

How long is Nemah Valley Road over Nemah River?

The structure is 73 ft (22.1 m) long with a longest span of 24 ft (7.4 m) and a deck 28 ft wide.

Who owns Nemah Valley Road over Nemah River?

It is owned by the County Highway Agency.