US Bridges

N 4950 E over Eagle Rock Canal

FairPosted for load

Jefferson County, Idaho · 0.2 N. 3.1 E. Ririe · Structure no. 000000000032425

Built
1950
75 years old
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
33 ft
1 main span
Daily traffic
560
2023 count
Owner
County
County Highway Agency

About this bridge

N 4950 E over Eagle Rock Canal is a wood or timber stringer/multi-beam or girder carrying N 4950 E over Eagle Rock Canal in Jefferson County, Idaho. It was built in 1950, so it is 75 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. Its operating status is: posted for load restriction.

It carries about 560 vehicles a day, roughly 12% of them trucks, projected to reach 840 by 2042. The structure is 33 ft (10.1 m) long and 24 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesN 4950 E
CrossesEagle Rock Canal
Location0.2 N. 3.1 E. Ririe
RouteCounty Highway 0
CountyJefferson County
StateIdaho
Coordinates43.63047, -111.71578
Functional classRural Minor 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 inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34 US tons
Inventory rating24 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadH 15
Structure length33 ft (10.1 m)
Longest span31 ft (9.4 m)
Deck width24 ft (7.3 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic560 (2023)
Projected traffic840 by 2042
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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$362,000 (2019 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was N 4950 E over Eagle Rock Canal built?

It was built in 1950, making it 75 years old in 2025.

What condition is N 4950 E over Eagle Rock Canal 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 March 2023.

How much traffic does N 4950 E over Eagle Rock Canal carry?

About 560 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is N 4950 E over Eagle Rock Canal?

The structure is 33 ft (10.1 m) long with a longest span of 31 ft (9.4 m) and a deck 24 ft wide.

Who owns N 4950 E over Eagle Rock Canal?

It is owned by the County Highway Agency.