US Bridges

Timber Island Road over Postun Bayou

FairPosted for load

Franklin County, Florida · 0.5 MI East of US98/SR30 · Structure no. 490002

Built
1962
63 years old
Condition
Fair
inspected November 2023
Type
Slab
Concrete
Length
270 ft
9 main spans
Daily traffic
133
2023 count
Owner
County
County Highway Agency

About this bridge

Timber Island Road over Postun Bayou is a concrete slab carrying Timber Island Road over Postun Bayou in Franklin County, Florida. It was built in 1962, so it is 63 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. Its operating status is: posted for load restriction.

It carries about 133 vehicles a day, roughly 3% of them trucks, projected to reach 146 by 2043. The structure is 270 ft (82.3 m) long and 30 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

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CarriesTimber Island Road
CrossesPostun Bayou
Location0.5 MI East of US98/SR30
RouteCounty Highway 0
CountyFranklin County
StateFlorida
Coordinates29.84352, -84.67137
Functional classRural Local

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.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating32 US tons
Inventory rating19 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans9
Design loadHS 20
Structure length270 ft (82.3 m)
Longest span30 ft (9.1 m)
Deck width30 ft (9.2 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic133 (2023)
Projected traffic146 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Timber Island Road over Postun Bayou built?

It was built in 1962, making it 63 years old in 2025.

What condition is Timber Island Road over Postun Bayou 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 Timber Island Road over Postun Bayou carry?

About 133 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Timber Island Road over Postun Bayou?

The structure is 270 ft (82.3 m) long with a longest span of 30 ft (9.1 m) and a deck 30 ft wide.

Who owns Timber Island Road over Postun Bayou?

It is owned by the County Highway Agency.