US Bridges

SR 21 over Dry Coulee

Fair

Franklin County, Washington · 3.6 N JCT SR 260 · Structure no. 0007173D0000000

Built
1963
62 years old
Condition
Fair
inspected July 2024
Type
Slab
Concrete Continuous
Length
80 ft
3 main spans
Daily traffic
165
2023 count
Owner
State
State Highway Agency

About this bridge

SR 21 over Dry Coulee is a concrete continuous slab carrying SR 21 over Dry Coulee in Franklin County, Washington. It was built in 1963, so it is 62 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 165 vehicles a day, roughly 35% of them trucks, projected to reach 198 by 2039. The structure is 80 ft (24.4 m) long and 26 ft wide. If it were closed, the detour would be 11.8 mi (19 km).

Location

Open in Google Maps
CarriesSR 21
CrossesDry Coulee
Location3.6 N JCT SR 260
RouteState Highway 21
CountyFranklin County
StateWashington
Coordinates46.68958, -118.52911
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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating27.9 US tons
Inventory rating21.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length80 ft (24.4 m)
Longest span39 ft (11.9 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic165 (2023)
Projected traffic198 by 2039
Trucks35%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.8 mi (19 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$1.1 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 21 over Dry Coulee built?

It was built in 1963, making it 62 years old in 2025.

What condition is SR 21 over Dry Coulee 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 July 2024.

How much traffic does SR 21 over Dry Coulee carry?

About 165 vehicles per day (2023 count), of which roughly 35% are trucks.

How long is SR 21 over Dry Coulee?

The structure is 80 ft (24.4 m) long with a longest span of 39 ft (11.9 m) and a deck 26 ft wide.

Who owns SR 21 over Dry Coulee?

It is owned by the State Highway Agency.