US Bridges

Diamond Creek Road over Wallace Creek

Good

Lemhi County, Idaho · 1.5 N 0.6 W Carmen · Structure no. 000000000032777

Built
2011
14 years old
Condition
Good
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
35 ft
1 main span
Daily traffic
70
2023 count
Owner
County
County Highway Agency

About this bridge

Diamond Creek Road over Wallace Creek is a steel stringer/multi-beam or girder carrying Diamond Creek Road over Wallace Creek in Lemhi County, Idaho. It was built in 2011, so it is 14 years old, younger than the Idaho average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 70 vehicles a day, roughly 10% of them trucks, projected to reach 105 by 2039. The structure is 35 ft (10.7 m) long and 21 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesDiamond Creek Road
CrossesWallace Creek
Location1.5 N 0.6 W Carmen
RouteCounty Highway 0
CountyLemhi County
StateIdaho
Coordinates45.26422, -113.90461
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating92 US tons
Inventory rating55 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckCorrugated steel
Main spans1
Design loadHS 20
Structure length35 ft (10.7 m)
Longest span30 ft (9.1 m)
Deck width21 ft (6.4 m)
Roadway width20 ft (6.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic70 (2023)
Projected traffic105 by 2039
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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 Diamond Creek Road over Wallace Creek built?

It was built in 2011, making it 14 years old in 2025.

What condition is Diamond Creek Road over Wallace Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in July 2023.

How much traffic does Diamond Creek Road over Wallace Creek carry?

About 70 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Diamond Creek Road over Wallace Creek?

The structure is 35 ft (10.7 m) long with a longest span of 30 ft (9.1 m) and a deck 21 ft wide.

Who owns Diamond Creek Road over Wallace Creek?

It is owned by the County Highway Agency.