US Bridges

NB Bluff ST SR-18 over Red Hills Parkway

Fair

Washington County, Utah · Bluff Street Interchange · Structure no. 1F 847

Built
2014
11 years old
Condition
Fair
inspected January 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
143 ft
1 main span
Daily traffic
9,348
2017 count
Owner
State
State Highway Agency

About this bridge

NB Bluff ST SR-18 over Red Hills Parkway is a prestressed concrete stringer/multi-beam or girder carrying NB Bluff ST SR-18 over Red Hills Parkway in Washington County, Utah. It was built in 2014, so it is 11 years old, younger 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 9,348 vehicles a day, roughly 19% of them trucks, projected to reach 11,218 by 2037. The structure is 143 ft (43.5 m) long and 43 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

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CarriesNB Bluff ST SR-18
CrossesRed Hills Parkway
LocationBluff Street Interchange
RouteState Highway 18
CountyWashington County
StateUtah
Coordinates37.13367, -113.60254
Functional classUrban Other Principal Arterial

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.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Last inspectionJanuary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating81 US tons
Inventory rating37.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length143 ft (43.5 m)
Longest span140 ft (42.6 m)
Deck width43 ft (13.1 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,348 (2017)
Projected traffic11,218 by 2037
Trucks19%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed9.9 mi (16 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkSTRAHNET connector

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 NB Bluff ST SR-18 over Red Hills Parkway built?

It was built in 2014, making it 11 years old in 2025.

What condition is NB Bluff ST SR-18 over Red Hills Parkway 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 January 2023.

How much traffic does NB Bluff ST SR-18 over Red Hills Parkway carry?

About 9,348 vehicles per day (2017 count), of which roughly 19% are trucks.

How long is NB Bluff ST SR-18 over Red Hills Parkway?

The structure is 143 ft (43.5 m) long with a longest span of 140 ft (42.6 m) and a deck 43 ft wide.

Who owns NB Bluff ST SR-18 over Red Hills Parkway?

It is owned by the State Highway Agency.