US Bridges

SR-21 over S. Prong of Black Creek

Good

Clay County, Florida · SR 21/S Prong Black Creek · Structure no. 710106

Built
2019
6 years old
Condition
Good
inspected April 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
120 ft
2 main spans
Daily traffic
9,200
2022 count
Owner
State
State Highway Agency

About this bridge

SR-21 over S. Prong of Black Creek is a prestressed concrete stringer/multi-beam or girder carrying SR-21 over S. Prong of Black Creek in Clay County, Florida. It was built in 2019, so it is 6 years old, younger than the Florida average of 41.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 9,200 vehicles a day, roughly 11% of them trucks, projected to reach 15,962 by 2044. The structure is 120 ft (36.6 m) long and 47 ft wide. If it were closed, the detour would be 26.7 mi (43 km).

Location

Open in Google Maps
CarriesSR-21
CrossesS. Prong of Black Creek
LocationSR 21/S Prong Black Creek
RouteState Highway 21
CountyClay County
StateFlorida
Coordinates29.94272, -81.89728
Functional classRural Minor Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61.6 US tons
Inventory rating47.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadHL 93
Structure length120 ft (36.6 m)
Longest span60 ft (18.3 m)
Deck width47 ft (14.4 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,200 (2022)
Projected traffic15,962 by 2044
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed26.7 mi (43 km)
TollOn a free road
National Highway SystemYes

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 SR-21 over S. Prong of Black Creek built?

It was built in 2019, making it 6 years old in 2025.

What condition is SR-21 over S. Prong of Black Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in April 2023.

How much traffic does SR-21 over S. Prong of Black Creek carry?

About 9,200 vehicles per day (2022 count), of which roughly 11% are trucks.

How long is SR-21 over S. Prong of Black Creek?

The structure is 120 ft (36.6 m) long with a longest span of 60 ft (18.3 m) and a deck 47 ft wide.

Who owns SR-21 over S. Prong of Black Creek?

It is owned by the State Highway Agency.