Total bridges
100
Public highway bridges in Monroe County
County profile · official public datasets
Monroe County, FL
100 public highway bridges tracked in the FHWA National Bridge Inventory: 34% rated Good, 59% Fair, 7% Poor.
- 100
- Public bridges
- 34%
- Good condition
- 7%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Monroe County pairs a higher-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.
- 54th
- of 67 on Poor share
- 7%
- Poor-condition share
- 100
- public highway bridges
- 1978
- avg year built
Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.
Monroe County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Monroe County ranks #54 of 67 Florida counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 7%). Monroe County, Florida contains 100 public highway bridges. Roughly 34% are rated “Good,” 59% “Fair,” and 7% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.
Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.
Source: FHWA National Bridge Inventory. See methodology for full definitions.
Good condition
34%
34 of 100 rated 7-9
Fair condition
59%
59 of 100 rated 5-6
Poor condition
7%
7 of 100 rated 4 or below
In-state Poor-share rank
#54 of 67
Among Florida counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 100 NBI-tracked bridges by lowest applicable component rating.
Good 34% (34)
Fair 59% (59)
Poor 7% (7)
Monroe County's Poor-condition bridges carry 9,482 vehicle crossings a day
That is 1% of the county's reported daily bridge traffic on 6.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,580 crossings a day against 12,022 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.
Computed over the 99 of 100 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
38% of Monroe County's bridges have passed the 50-year mark
38 of the 100 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 34% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.
Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.
One structure carries 33.6% of the county's Poor-condition bridge traffic
Card Sound Road over Tubbys Creek, built 1969, carries 3,182 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 7-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 9,482 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Monroe County's bridges were built
100 bridges with a recorded construction year, grouped by decade
- 1910s 1
1910–1919
1 bridges
- 1930s 1
1930–1939
1 bridges
- 1950s 8
1950–1959
8 bridges
- 1960s
1960–1969
24 bridges
- 1970s 11
1970–1979
11 bridges
- 1980s
1980–1989
36 bridges
- 1990s 5
1990–1999
5 bridges
- 2000s 13
2000–2009
13 bridges
- 2010s 1
2010–2019
1 bridges
What this shows Construction peaked in the 1980s, when 36 of the county's bridges still in the inventory were built, which is 36% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1978, 5 years older than the Florida average of 1983.
How Monroe County compares with Florida's closest counties by inventory size
The 5 Florida counties nearest Monroe County in number of bridges, with their condition splits. Its 7% Poor share is the 4th-lowest of these 6. Its average build year of 1978 against a peer-group mean of 1978 is in line with the group.
Showing the 5 closest of 66 Florida counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Flagler County | 105 | 57.1% | 41% | 1.9% | 1981 |
| Nassau County | 104 | 49% | 48.1% | 2.9% | 1977 |
| Monroe County (this page) | 100 | 34% | 59% | 7% | 1978 |
| Washington County | 99 | 43.4% | 46.5% | 10.1% | 1984 |
| Baker County | 93 | 26.9% | 64.5% | 8.6% | 1966 |
| Clay County | 90 | 47.8% | 48.9% | 3.3% | 1984 |
Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Monroe County's. Source: FHWA National Bridge Inventory, 2024 release.
Nationwide counties with similar inventory size or average build year
Two NBI-derived peer sets for Monroe County, both outside Florida so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside FL (100 bridges here).
- Ketchikan Gateway County, AK · 100 bridges
- Gunnison County, CO · 100 bridges
- Fayette County, IN · 100 bridges
- LaGrange County, IN · 100 bridges
Similar average build year
Nearest mean year-built outside FL (1978 here).
- Orange County, CA · avg 1978 · 1,164 bridges
- Sumner County, KS · avg 1978 · 659 bridges
- Allen County, IN · avg 1978 · 613 bridges
- Livingston County, IL · avg 1978 · 579 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (59)
US 1 (SR 5)
FairOver: CHANNEL #5
FIESTA-CRAIG KEY (MM 71), Monroe, FL
Built 1982 Load: 7.2 t ADT: 11,500
US 1 (SR 5)
FairOver: LONG KEY CHANNEL
LONG KEY (MM 63.2), Monroe, FL
Built 1981 Load: 10.1 t ADT: 13,200
116th Street
FairOver: Venice Waterway
200Ft. S of US 1 MM 52.9, Monroe, FL
Built 1967 Load: 10.8 t ADT: 593
US 1 (SR 5)
FairOver: CHANNEL #2
MATECUMBE KEY (MM 73.0), Monroe, FL
Built 1981 Load: 13.1 t ADT: 12,700
Watson Road
FairOver: Bogie Channel
3.5 Mi E of SR 5(MM 30.5), Monroe, FL
Built 1967 Load: 14.7 t ADT: 1,300
Valois Blvd.
FairOver: Canal
200Ft. E of CR-905, Monroe, FL
Built 1995 Load: 18.5 t ADT: 282
US 1 (SR 5)
FairOver: MOSER CHANNEL
MARATHON KEY (MM 40-46.6), Monroe, FL
Built 1982 Load: 19.6 t ADT: 11,300
FLEMING KEY ROAD
FairOver: GARRISON BIGHT
1.5 KM N OF US 1, Monroe, FL
Built 1965 Load: 20.5 t ADT: 250
112th Street
FairOver: Caloosa Channel
100Ft. S of US-1 MM 52.7, Monroe, FL
Built 1965 Load: 22.2 t ADT: 593
Card Sound Road
FairOver: I.C.W.W
11.0 Miles SE of US 1, Monroe, FL
Built 1969 Load: 25.6 t ADT: 3,157
Yellow Tail Road
FairOver: Un-Named Canal
40Ft. N of Aviation Blvd., Monroe, FL
Built 1983 Load: 25.9 t ADT: 261
US 1 (SR 5)
FairOver: NILES CHANNEL
SUMMERLAND KEY (MM 25.5), Monroe, FL
Built 1981 Load: 26.5 t ADT: 16,900
MAIN PARK ROAD
FairOver: BUTTONWOOD CANAL
37.33 MILES FROM PARK ENT, Monroe, FL
Built 1957 Load: 27.2 t ADT: 690
Duck Key Drive
FairOver: Duck Key Channel
0.5 Mile E of US1 MM 61.1, Monroe, FL
Built 1955 Load: 27.6 t ADT: 830
CR 905A
FairOver: Steam Boat Creek
1.6 Miles N of CR 905, Monroe, FL
Built 1968 Load: 27.6 t ADT: 3,182
Old State Road 4A
FairOver: Sugarloaf Creek
5 Mi. E & S of US-1 MM 17, Monroe, FL
Built 1968 Load: 28.7 t ADT: 617
Palm Avenue
FairOver: Garrison Bight
0.2 Mile W of US-1, Monroe, FL
Built 1965 Load: 29.3 t ADT: 15,026
Sadowski Cswy.
FairOver: Beamers Channel
0.2Mi. E of US-1 (MM53.5), Monroe, FL
Built 2006 Load: 29.4 t ADT: 7,027
Boca Chica(CR-941)
FairOver: Geiger Key Cut
2.8Mi S of SR-5 (MM 10.7), Monroe, FL
Built 1955 Load: 30.0 t ADT: 592
Bahama Road
FairOver: Dougs Canal
200Ft S/O US1 at MM 98.4, Monroe, FL
Built 1962 Load: 30.8 t ADT: 51
Caribbean Drive
FairOver: Summerland Key Cove
100Ft. E of US1 At MM24.5, Monroe, FL
Built 1960 Load: 31.8 t ADT: 781
Beach Road
FairOver: Calley Slough
US-1 MM 102, Monroe, FL
Built 1967 Load: 32.1 t ADT: 1,869
Fern Avenue
FairOver: Joes Canal
230Ft. North of Watson Bl, Monroe, FL
Built 1960 Load: 32.1 t ADT: 700
MAIN PARK ROAD
FairOver: TAYLOR SLOUGH
0.9 MILES FROM PARK ENTRA, Monroe, FL
Built 2000 Load: 32.7 t ADT: 943
MAIN PARK ROAD
FairOver: TAYLOR SLOUGH
1.1 MILES FROM PARK ENTRA, Monroe, FL
Built 2000 Load: 32.7 t ADT: 943
US 1 SB (900016)
FairOver: BIG SPANISH CHANNEL
BAHIA HONDA KEY (MM 36.0), Monroe, FL
Built 1972 Load: 33.3 t ADT: 6,850
US 1 NB (900045)
FairOver: BIG SPANISH CHANNEL
BAHIA HONDA KEY (MM 36.0), Monroe, FL
Built 1972 Load: 33.3 t ADT: 6,850
Duck Key Drive
FairOver: Toms Harbor Channel
50Ft. E of US-1 MM61, Monroe, FL
Built 1967 Load: 33.3 t ADT: 1,700
Park Entrance Road
FairOver: Little Crawl Key Channel
220Ft. South of US-1, Monroe, FL
Built 2010 Load: 33.7 t ADT: 50
25th Street
FairOver: Un-named Canal
0.2 Mile S of US-1 MM48.5, Monroe, FL
Built 1967 Load: 34.1 t ADT: 600
CR 905A Card Sound
FairOver: Saunders Creek
3.5 Miles N of CR 905, Monroe, FL
Built 1969 Load: 34.7 t ADT: 3,184
US 1 (SR 5)
FairOver: SHARK CHANNEL
SHARK KEY (MM 11.3), Monroe, FL
Built 1979 Load: 34.9 t ADT: 17,600
US 1 (SR 5)
FairOver: SALT RUN
KEY WEST (MM 2.3), Monroe, FL
Built 1992 Load: 34.9 t ADT: 38,500
US 1 (SR 5)
FairOver: LOWER SUGARLOAF CHANNEL
SUGARLOAF KEY (MM 15.5), Monroe, FL
Built 1981 Load: 35.4 t ADT: 17,600
US 1 SB (900074)
FairOver: BOCA CHICA CHANNEL
BOCA CHICA KEY (MM 6.0), Monroe, FL
Built 1973 Load: 35.9 t ADT: 13,500
US 1 (SR 5)
FairOver: SPANISH HARBOR CHANNEL
BIG PINE KEY (MM 33.5), Monroe, FL
Built 1982 Load: 36.1 t ADT: 13,700
US 1 NB (900127)
FairOver: TAVERNIER CREEK
TAVERNIER KEY (MM 90.8), Monroe, FL
Built 1978 Load: 36.3 t ADT: 15,000
US 1 (SR 5)
FairOver: TEATABLE RELIEF
MATECUMBE KEY (MM 79.4), Monroe, FL
Built 1979 Load: 37.6 t ADT: 15,800
US 1 (SR 5)
FairOver: BOW CHANNEL
N SUGARLOAF KEY (MM 20.2), Monroe, FL
Built 1982 Load: 37.6 t ADT: 16,900
US 1 (SR 5)
FairOver: SADDLE BUNCH #2
N OF BOCA CHICA (MM14.6), Monroe, FL
Built 1981 Load: 39.1 t ADT: 17,600
Copa D Oro Road
FairOver: Un-Named Canal
150Ft. S of Sombrero Blvd, Monroe, FL
Built 1983 Load: 39.3 t ADT: 243
US 1 (SR 5)
FairOver: HARRIS CHANNEL
SUGARLOAF KEY (MM 16.5), Monroe, FL
Built 1982 Load: 40.0 t ADT: 16,900
US 1 (SR 5)
FairOver: NORTH HARRIS CHANNEL
SUGARLOAF KEY (MM 17.7), Monroe, FL
Built 1981 Load: 40.0 t ADT: 16,900
US 1 (SR 5)
FairOver: MISSOURI LITTLE DUCK CH.
LITTLE DUCK KEY (MM 39.6), Monroe, FL
Built 1981 Load: 40.3 t ADT: 11,300
US-1 (SR-5)
FairOver: OHIO-BAHIA HONDA CHANL
BAHIA HONDA KEY (MM 38.5), Monroe, FL
Built 1981 Load: 40.3 t ADT: 11,300
US 1 (SR 5)
FairOver: TORCH CHANNEL
TORCH KEY (MM 28.0), Monroe, FL
Built 1982 Load: 40.6 t ADT: 18,000
Coco Plum Drive
FairOver: Bonefish Bay
0.3 mi. E of US-1 MM 54.1, Monroe, FL
Built 1977 Load: 41.2 t ADT: 618
US 1 (SR 5)
FairOver: TOMS HARBOR CUT
DUCK KEY (MM 61.4), Monroe, FL
Built 1980 Load: 41.5 t ADT: 12,700
US 1 (SR 5)
FairOver: TORCH RAMROD CHANNEL
TORCH RAMROD KEY(MM 27.7), Monroe, FL
Built 1982 Load: 42.5 t ADT: 18,300
US 1 (SR 5)
FairOver: INDIAN KEY CHANNEL
MATECUMBE KEY (MM 78.0), Monroe, FL
Built 1981 Load: 43.5 t ADT: 15,800
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.