US Bridges

Northside RD over Big Creek;se.Calder Br

Fair

Shoshone County, Idaho · 0.1 S. 3.7 E. Calder · Structure no. 000000000030840

Built
1960
65 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
102 ft
1 main span
Daily traffic
50
2023 count
Owner
County
County Highway Agency

About this bridge

Northside RD over Big Creek;se.Calder Br is a steel stringer/multi-beam or girder carrying Northside RD over Big Creek;se.Calder Br in Shoshone County, Idaho. It was built in 1960, so it is 65 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 50 vehicles a day, roughly 10% of them trucks, projected to reach 75 by 2039. The structure is 102 ft (31.1 m) long and 15 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesNorthside RD
CrossesBig Creek;se.Calder Br
Location0.1 S. 3.7 E. Calder
RouteCounty Highway 0
CountyShoshone County
StateIdaho
Coordinates47.27297, -116.11083
Functional classRural Local

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 inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating49.1 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1 (+2 approach)
Design loadHS 20
Structure length102 ft (31.1 m)
Longest span58 ft (17.7 m)
Deck width15 ft (4.7 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2023)
Projected traffic75 by 2039
Trucks10%
Lanes on structure1
Traffic directionOne-lane bridge for two-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 Northside RD over Big Creek;se.Calder Br built?

It was built in 1960, making it 65 years old in 2025.

What condition is Northside RD over Big Creek;se.Calder Br 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 August 2023.

How much traffic does Northside RD over Big Creek;se.Calder Br carry?

About 50 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Northside RD over Big Creek;se.Calder Br?

The structure is 102 ft (31.1 m) long with a longest span of 58 ft (17.7 m) and a deck 15 ft wide.

Who owns Northside RD over Big Creek;se.Calder Br?

It is owned by the County Highway Agency.