US Bridges

Moccasin-Napias RD over Napias Creek

Poor

Lemhi County, Idaho · No Data Entered · Structure no. 041301000001052

Built
1953
72 years old, rebuilt 1995
Condition
Poor
inspected November 2024
Type
Slab
Wood or Timber
Length
26 ft
1 main span
Daily traffic
25
1994 count
Owner
Federal
U.S. Forest Service

About this bridge

Moccasin-Napias RD over Napias Creek is a wood or timber slab carrying Moccasin-Napias RD over Napias Creek in Lemhi County, Idaho. It was built in 1953 and reconstructed in 1995, so it is 72 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 25 vehicles a day, projected to reach 175 by 2014. The structure is 26 ft (7.9 m) long and 24 ft wide. If it were closed, the detour would be 14.9 mi (24 km).

CarriesMoccasin-Napias RD
CrossesNapias Creek
LocationNo Data Entered
RouteFederal Lands Road 60076
StateIdaho
Coordinates45.15413, -114.16989
Functional classRural Local

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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating35.1 US tons
Inventory rating26.8 US tons

Structure

Structure typeSlab
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadH 20
Structure length26 ft (7.9 m)
Longest span25 ft (7.7 m)
Deck width24 ft (7.3 m)
Roadway width22 ft (6.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25 (1994)
Projected traffic175 by 2014
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.9 mi (24 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerU.S. Forest Service
Maintained byU.S. Forest Service
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Moccasin-Napias RD over Napias Creek built?

It was built in 1953, making it 72 years old in 2025. It was reconstructed in 1995.

What condition is Moccasin-Napias RD over Napias Creek 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 November 2024.

How much traffic does Moccasin-Napias RD over Napias Creek carry?

About 25 vehicles per day (1994 count).

How long is Moccasin-Napias RD over Napias Creek?

The structure is 26 ft (7.9 m) long with a longest span of 25 ft (7.7 m) and a deck 24 ft wide.

Who owns Moccasin-Napias RD over Napias Creek?

It is owned by the U.S. Forest Service.