US Bridges

I 15N over Twain Ave

Fair

Clark County, Nevada · Las Vegas · Structure no. H 804N

Built
1964
61 years old, rebuilt 1998
Condition
Fair
inspected January 2023
Type
Culvert
Concrete
Length
38 ft
1 main span
Daily traffic
121,500
2021 count
Owner
State
State Highway Agency

About this bridge

I 15N over Twain Ave is a concrete culvert carrying I 15N over Twain Ave in Clark County, Nevada. It was built in 1964 and reconstructed in 1998, so it is 61 years old, older than the Nevada average of 36.4 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 121,500 vehicles a day, roughly 7% of them trucks, projected to reach 289,536 by 2040. The structure is 38 ft (11.7 m) long and 85 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesI 15N
CrossesTwain Ave
LocationLas Vegas
RouteInterstate 15
CountyClark County
StateNevada
Coordinates36.11974, -115.18047
Functional classUrban 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
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.9 US tons
Inventory rating38.5 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length38 ft (11.7 m)
Longest span34 ft (10.4 m)
Deck width85 ft (25.8 m)
Roadway width82 ft (24.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic121,500 (2021)
Projected traffic289,536 by 2040
Trucks7%
Lanes on structure7
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed0.6 mi (1 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 15N over Twain Ave built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 1998.

What condition is I 15N over Twain Ave 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 I 15N over Twain Ave carry?

About 121,500 vehicles per day (2021 count), of which roughly 7% are trucks.

How long is I 15N over Twain Ave?

The structure is 38 ft (11.7 m) long with a longest span of 34 ft (10.4 m) and a deck 85 ft wide.

Who owns I 15N over Twain Ave?

It is owned by the State Highway Agency.