US Bridges

STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr.

Fair

Clearwater County, Idaho · 0.3 N. 2.7 E. Orofino · Structure no. 000000000020275

Built
1951
74 years old
Condition
Fair
inspected June 2023
Type
Tee Beam
Concrete
Length
42 ft
1 main span
Daily traffic
2,800
2023 count
Owner
County
County Highway Agency

About this bridge

STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr. is a concrete tee beam carrying STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr. in Clearwater County, Idaho. It was built in 1951, so it is 74 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 2,800 vehicles a day, roughly 5% of them trucks, projected to reach 4,200 by 2042. The structure is 42 ft (12.8 m) long and 28 ft wide. If it were closed, the detour would be 16.2 mi (26 km).

Location

Open in Google Maps
CarriesSTC4782;GRANGEMONT
CrossesWhiskey Cr.;orofino Cr.
Location0.3 N. 2.7 E. Orofino
RouteCounty Highway 4782
CountyClearwater County
StateIdaho
Coordinates46.48547, -116.19803
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating35.1 US tons
Inventory rating21.1 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length42 ft (12.8 m)
Longest span40 ft (12.2 m)
Deck width28 ft (8.4 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,800 (2023)
Projected traffic4,200 by 2042
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed16.2 mi (26 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$730,000 (2021 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr. built?

It was built in 1951, making it 74 years old in 2025.

What condition is STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr. 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 June 2023.

How much traffic does STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr. carry?

About 2,800 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr.?

The structure is 42 ft (12.8 m) long with a longest span of 40 ft (12.2 m) and a deck 28 ft wide.

Who owns STC4782;GRANGEMONT over Whiskey Cr.;orofino Cr.?

It is owned by the County Highway Agency.