US Bridges

Cresent Bar RD over Wanapum Lake

Good

Grant County, Washington · Cresent Bar · Structure no. 087579000000000

Built
2008
17 years old
Condition
Good
inspected December 2023
Type
Tee Beam
Prestressed Concrete
Length
130 ft
1 main span
Daily traffic
1,147
2021 count
Owner
County
County Highway Agency

About this bridge

Cresent Bar RD over Wanapum Lake is a prestressed concrete tee beam carrying Cresent Bar RD over Wanapum Lake in Grant County, Washington. It was built in 2008, so it is 17 years old, younger than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1,147 vehicles a day, roughly 27% of them trucks, projected to reach 2,230 by 2043. The structure is 130 ft (39.6 m) long and 44 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

CarriesCresent Bar RD
CrossesWanapum Lake
LocationCresent Bar
RouteCounty Highway 31790
Coordinates47.21509, -119.99457
Functional classRural Minor Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations on dry land well above flood water elevations
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.9 US tons
Inventory rating37.8 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 25 or greater
Structure length130 ft (39.6 m)
Longest span129 ft (39.3 m)
Deck width44 ft (13.4 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,147 (2021)
Projected traffic2,230 by 2043
Trucks27%
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$5.1 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Cresent Bar RD over Wanapum Lake built?

It was built in 2008, making it 17 years old in 2025.

What condition is Cresent Bar RD over Wanapum Lake in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in December 2023.

How much traffic does Cresent Bar RD over Wanapum Lake carry?

About 1,147 vehicles per day (2021 count), of which roughly 27% are trucks.

How long is Cresent Bar RD over Wanapum Lake?

The structure is 130 ft (39.6 m) long with a longest span of 129 ft (39.3 m) and a deck 44 ft wide.

Who owns Cresent Bar RD over Wanapum Lake?

It is owned by the County Highway Agency.