US Bridges

I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap

Fair

Iron County, Utah · 1.5 Mi.No.So.Parowan Int. · Structure no. 1F 260

Built
1973
52 years old
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
105 ft
1 main span
Daily traffic
24,884
2022 count
Owner
State
State Highway Agency

About this bridge

I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap is a prestressed concrete stringer/multi-beam or girder carrying I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap in Iron County, Utah. It was built in 1973, so it is 52 years old, older than the Utah average of 40.1 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 24,884 vehicles a day, roughly 45% of them trucks, projected to reach 29,861 by 2042. The structure is 105 ft (32.1 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-15 (SR-15) Nbl
CrossesCo. Rd. to Parowan Gap
Location1.5 Mi.No.So.Parowan Int.
RouteInterstate 15
CountyIron County
StateUtah
Coordinates37.84889, -112.84333
Functional classRural Principal Arterial - Interstate

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.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating47.8 US tons
Inventory rating29.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length105 ft (32.1 m)
Longest span100 ft (30.5 m)
Deck width44 ft (13.4 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic24,884 (2022)
Projected traffic29,861 by 2042
Trucks45%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap built?

It was built in 1973, making it 52 years old in 2025.

What condition is I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap 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 March 2023.

How much traffic does I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap carry?

About 24,884 vehicles per day (2022 count), of which roughly 45% are trucks.

How long is I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap?

The structure is 105 ft (32.1 m) long with a longest span of 100 ft (30.5 m) and a deck 44 ft wide.

Who owns I-15 (SR-15) Nbl over Co. Rd. to Parowan Gap?

It is owned by the State Highway Agency.