US Bridges

Sprenger Road over Thorn Creek

Fair

Latah County, Idaho · 2.3 N. 4.8 W. Genesee · Structure no. 000000000029570

Built
1935
90 years old
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
28 ft
1 main span
Daily traffic
30
2023 count
Owner
Local
Other Local Agency

About this bridge

Sprenger Road over Thorn Creek is a steel stringer/multi-beam or girder carrying Sprenger Road over Thorn Creek in Latah County, Idaho. It was built in 1935, so it is 90 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 5 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 30 vehicles a day, roughly 10% of them trucks, projected to reach 45 by 2039. The structure is 28 ft (8.5 m) long and 19 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesSprenger Road
CrossesThorn Creek
Location2.3 N. 4.8 W. Genesee
RouteCounty Highway 0
CountyLatah County
StateIdaho
Coordinates46.58122, -117.02775
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
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating49.1 US tons
Inventory rating29 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length28 ft (8.5 m)
Longest span25 ft (7.6 m)
Deck width19 ft (5.7 m)
Roadway width18 ft (5.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30 (2023)
Projected traffic45 by 2039
Trucks10%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerOther Local Agency
Maintained byOther Local Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$312,000 (2019 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Sprenger Road over Thorn Creek built?

It was built in 1935, making it 90 years old in 2025.

What condition is Sprenger Road over Thorn Creek 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 May 2023.

How much traffic does Sprenger Road over Thorn Creek carry?

About 30 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Sprenger Road over Thorn Creek?

The structure is 28 ft (8.5 m) long with a longest span of 25 ft (7.6 m) and a deck 19 ft wide.

Who owns Sprenger Road over Thorn Creek?

It is owned by the Other Local Agency.