US Bridges

Stc 4771;SOUTHWICK over Potlatch River

Good

Latah County, Idaho · 0.7 N. 0.6 E. Kendrick · Structure no. 000000000020266

Built
1995
30 years old
Condition
Good
inspected September 2024
Type
Tee Beam
Prestressed Concrete
Length
145 ft
1 main span
Daily traffic
700
2023 count
Owner
County
County Highway Agency

About this bridge

Stc 4771;SOUTHWICK over Potlatch River is a prestressed concrete tee beam carrying Stc 4771;SOUTHWICK over Potlatch River in Latah County, Idaho. It was built in 1995, so it is 30 years old, younger than the Idaho average of 45.3 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 700 vehicles a day, roughly 23% of them trucks, projected to reach 1,050 by 2042. The structure is 145 ft (44.2 m) long and 29 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

CarriesStc 4771;SOUTHWICK
CrossesPotlatch River
Location0.7 N. 0.6 E. Kendrick
RouteCounty Highway 4771
StateIdaho
Coordinates46.62428, -116.633
Functional classRural Major 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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations on dry land well above flood water elevations
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 alignment6: Equal to present minimum criteria
Operating rating72 US tons
Inventory rating24 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 25 or greater
Structure length145 ft (44.2 m)
Longest span142 ft (43.3 m)
Deck width29 ft (8.7 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic700 (2023)
Projected traffic1,050 by 2042
Trucks23%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Stc 4771;SOUTHWICK over Potlatch River built?

It was built in 1995, making it 30 years old in 2025.

What condition is Stc 4771;SOUTHWICK over Potlatch River 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 September 2024.

How much traffic does Stc 4771;SOUTHWICK over Potlatch River carry?

About 700 vehicles per day (2023 count), of which roughly 23% are trucks.

How long is Stc 4771;SOUTHWICK over Potlatch River?

The structure is 145 ft (44.2 m) long with a longest span of 142 ft (43.3 m) and a deck 29 ft wide.

Who owns Stc 4771;SOUTHWICK over Potlatch River?

It is owned by the County Highway Agency.