US Bridges

US 20 over Grove Creek

Fair

Blaine County, Idaho · 12.1 W. Carey · Structure no. 000000000015090

Built
1971
54 years old
Condition
Fair
inspected July 2021
Type
Tee Beam
Concrete
Length
32 ft
1 main span
Daily traffic
970
2023 count
Owner
State
State Highway Agency

About this bridge

US 20 over Grove Creek is a concrete tee beam carrying US 20 over Grove Creek in Blaine County, Idaho. It was built in 1971, so it is 54 years old, older than the Idaho average of 45.3 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 970 vehicles a day, roughly 10% of them trucks, projected to reach 1,455 by 2042. The structure is 32 ft (9.8 m) long and 33 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesUS 20
CrossesGrove Creek
Location12.1 W. Carey
RouteU.S. Route 20
CountyBlaine County
StateIdaho
Coordinates43.33092, -114.16333
Functional classRural Principal Arterial - Other

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2021
Inspection intervalevery 48 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 rating58 US tons
Inventory rating34 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length32 ft (9.8 m)
Longest span30 ft (9.1 m)
Deck width33 ft (10.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic970 (2023)
Projected traffic1,455 by 2042
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 US 20 over Grove Creek built?

It was built in 1971, making it 54 years old in 2025.

What condition is US 20 over Grove Creek 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 2021.

How much traffic does US 20 over Grove Creek carry?

About 970 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is US 20 over Grove Creek?

The structure is 32 ft (9.8 m) long with a longest span of 30 ft (9.1 m) and a deck 33 ft wide.

Who owns US 20 over Grove Creek?

It is owned by the State Highway Agency.