US Bridges

I-75 SB over Salt Marsh

Fair

Manatee County, Florida · 2.5MI South of US-301 · Structure no. 130101

Built
1980
45 years old, rebuilt 2024
Condition
Fair
inspected November 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
1,140 ft
19 main spans
Daily traffic
120,500
2024 count
Owner
State
State Highway Agency

About this bridge

I-75 SB over Salt Marsh is a prestressed concrete stringer/multi-beam or girder carrying I-75 SB over Salt Marsh in Manatee County, Florida. It was built in 1980 and reconstructed in 2024, so it is 45 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 120,500 vehicles a day, roughly 13% of them trucks, projected to reach 150,625 by 2044. The structure is 1,140 ft (347.5 m) long and 71 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesI-75 SB
CrossesSalt Marsh
Location2.5MI South of US-301
RouteInterstate 75
CountyManatee County
StateFlorida
Coordinates27.50626, -82.49162
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.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating68 US tons
Inventory rating47.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans19
Design loadHS 20 + Mod
Structure length1,140 ft (347.5 m)
Longest span60 ft (18.3 m)
Deck width71 ft (21.5 m)
Roadway width55 ft (16.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic120,500 (2024)
Projected traffic150,625 by 2044
Trucks13%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was I-75 SB over Salt Marsh built?

It was built in 1980, making it 45 years old in 2025. It was reconstructed in 2024.

What condition is I-75 SB over Salt Marsh 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 November 2023.

How much traffic does I-75 SB over Salt Marsh carry?

About 120,500 vehicles per day (2024 count), of which roughly 13% are trucks.

How long is I-75 SB over Salt Marsh?

The structure is 1,140 ft (347.5 m) long with a longest span of 60 ft (18.3 m) and a deck 71 ft wide.

Who owns I-75 SB over Salt Marsh?

It is owned by the State Highway Agency.