US Bridges

I-275 NB over 18th Ave. South

Fair

Pinellas County, Florida · 2.3MI North of SR-682 · Structure no. 150157

Built
1982
43 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
159 ft
3 main spans
Daily traffic
54,750
2023 count
Owner
State
State Highway Agency

About this bridge

I-275 NB over 18th Ave. South is a prestressed concrete stringer/multi-beam or girder carrying I-275 NB over 18th Ave. South in Pinellas County, Florida. It was built in 1982, so it is 43 years old, older than the Florida average of 41.3 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 54,750 vehicles a day, roughly 7% of them trucks, projected to reach 68,438 by 2042. The structure is 159 ft (48.4 m) long and 79 ft wide.

Location

Open in Google Maps
CarriesI-275 NB
Crosses18th Ave. South
Location2.3MI North of SR-682
RouteInterstate 275
CountyPinellas County
StateFlorida
Coordinates27.75197, -82.67707
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionOctober 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 rating65 US tons
Inventory rating50 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length159 ft (48.4 m)
Longest span92 ft (27.9 m)
Deck width79 ft (24.2 m)
Roadway width76 ft (23.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic54,750 (2023)
Projected traffic68,438 by 2042
Trucks7%
Lanes on structure5
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
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-275 NB over 18th Ave. South built?

It was built in 1982, making it 43 years old in 2025.

What condition is I-275 NB over 18th Ave. South 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 October 2023.

How much traffic does I-275 NB over 18th Ave. South carry?

About 54,750 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is I-275 NB over 18th Ave. South?

The structure is 159 ft (48.4 m) long with a longest span of 92 ft (27.9 m) and a deck 79 ft wide.

Who owns I-275 NB over 18th Ave. South?

It is owned by the State Highway Agency.