US Bridges

I 90B over S.Fk.Cda R;I-90B Arch

Poor

Shoshone County, Idaho · In Wallace;bank St. · Structure no. 000000000017250

Built
1940
85 years old
Condition
Poor
inspected September 2024
Type
Culvert
Concrete
Length
94 ft
1 main span
Daily traffic
2,300
2023 count
Owner
State
State Highway Agency

About this bridge

I 90B over S.Fk.Cda R;I-90B Arch is a concrete culvert carrying I 90B over S.Fk.Cda R;I-90B Arch in Shoshone County, Idaho. It was built in 1940, so it is 85 years old, older than the Idaho average of 45.3 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 2,300 vehicles a day, roughly 5% of them trucks, projected to reach 3,450 by 2042. The structure is 94 ft (28.7 m) long and 296 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 90B
CrossesS.Fk.Cda R;I-90B Arch
LocationIn Wallace;bank St.
RouteInterstate 90
CountyShoshone County
StateIdaho
Coordinates47.47161, -115.91964
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
Channel and channel protection7 GoodSome minor problems.
Culvert4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionSeptember 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length94 ft (28.7 m)
Longest span94 ft (28.7 m)
Deck width296 ft (90.2 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,300 (2023)
Projected traffic3,450 by 2042
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.3 million (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I 90B over S.Fk.Cda R;I-90B Arch built?

It was built in 1940, making it 85 years old in 2025.

What condition is I 90B over S.Fk.Cda R;I-90B Arch 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 2024.

How much traffic does I 90B over S.Fk.Cda R;I-90B Arch carry?

About 2,300 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is I 90B over S.Fk.Cda R;I-90B Arch?

The structure is 94 ft (28.7 m) long with a longest span of 94 ft (28.7 m) and a deck 296 ft wide.

Who owns I 90B over S.Fk.Cda R;I-90B Arch?

It is owned by the State Highway Agency.