US Bridges

SR 21 over San Poil River

Poor

Ferry County, Washington · 25.1 N Lincoln CO · Structure no. 0001513B0000000

Built
1931
94 years old
Condition
Poor
inspected September 2023
Type
Tee Beam
Concrete
Length
48 ft
1 main span
Daily traffic
193
2023 count
Owner
State
State Highway Agency

About this bridge

SR 21 over San Poil River is a concrete tee beam carrying SR 21 over San Poil River in Ferry County, Washington. It was built in 1931, so it is 94 years old, older than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 193 vehicles a day, roughly 20% of them trucks, projected to reach 268 by 2039. The structure is 48 ft (14.6 m) long and 27 ft wide. If it were closed, the detour would be 60.3 mi (97 km).

Location

Open in Google Maps
CarriesSR 21
CrossesSan Poil River
Location25.1 N Lincoln CO
RouteState Highway 21
CountyFerry County
StateWashington
Coordinates48.27583, -118.71547
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy3: Basically intolerable, requiring high priority of corrective action
Approach roadway alignment8: Equal to present desirable criteria
Operating rating41.1 US tons
Inventory rating31.7 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length48 ft (14.6 m)
Longest span44 ft (13.4 m)
Deck width27 ft (8.3 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic193 (2023)
Projected traffic268 by 2039
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed60.3 mi (97 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$638,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 21 over San Poil River built?

It was built in 1931, making it 94 years old in 2025.

What condition is SR 21 over San Poil River in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in September 2023.

How much traffic does SR 21 over San Poil River carry?

About 193 vehicles per day (2023 count), of which roughly 20% are trucks.

How long is SR 21 over San Poil River?

The structure is 48 ft (14.6 m) long with a longest span of 44 ft (13.4 m) and a deck 27 ft wide.

Who owns SR 21 over San Poil River?

It is owned by the State Highway Agency.