Total bridges
34
Public highway bridges in Plaquemines County
County profile · official public datasets
Plaquemines County, LA
34 public highway bridges tracked in the FHWA National Bridge Inventory: 17.6% rated Good, 61.8% Fair, 20.6% Poor.
- 34
- Public bridges
- 17.6%
- Good condition
- 20.6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Plaquemines County posts a higher-than-median Poor-condition share among rated counties in the state across rated county bridge inventory.
- 57th
- of 64 on Poor share
- 20.6%
- Poor-condition share
- 34
- public highway bridges
- 1981
- 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.
Plaquemines County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Plaquemines County ranks #57 of 64 Louisiana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 20.6%). Plaquemines County, Louisiana contains 34 public highway bridges. Roughly 17.6% are rated “Good,” 61.8% “Fair,” and 20.6% “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
17.6%
6 of 34 rated 7-9
Fair condition
61.8%
21 of 34 rated 5-6
Poor condition
20.6%
7 of 34 rated 4 or below
In-state Poor-share rank
#57 of 64
Among Louisiana counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 34 NBI-tracked bridges by lowest applicable component rating.
Good 17.6% (6)
Fair 61.8% (21)
Poor 20.6% (7)
Plaquemines County's Poor-condition bridges carry 250 vehicle crossings a day
That is 0.1% of the county's reported daily bridge traffic on 13% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 83 crossings a day against 8,608 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 23 of 34 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
44.1% of Plaquemines County's bridges have passed the 50-year mark
15 of the 34 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 17.6% 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 60% of the county's Poor-condition bridge traffic
GRAVOLET RD over DRAINAGE CANAL, built 1968, carries 150 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 250 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Plaquemines County's bridges were built
34 bridges with a recorded construction year, grouped by decade
- 1950s 1
1950–1959
1 bridges
- 1960s
1960–1969
12 bridges
- 1970s
1970–1979
7 bridges
- 1980s 4
1980–1989
4 bridges
- 1990s 3
1990–1999
3 bridges
- 2000s 4
2000–2009
4 bridges
- 2010s 3
2010–2019
3 bridges
What this shows Construction peaked in the 1960s, when 12 of the county's bridges still in the inventory were built, which is 35.3% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1981) matches the Louisiana average (1982).
How Plaquemines County compares with Louisiana's closest counties by inventory size
The 5 Louisiana counties nearest Plaquemines County in number of bridges, with their condition splits. Its 20.6% Poor share is the 5th-lowest of these 6. Its average build year of 1981 against a peer-group mean of 1980 is in line with the group.
Showing the 5 closest of 63 Louisiana counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Pointe Coupee County | 50 | 22% | 52% | 26% | 1970 |
| St. Bernard County | 47 | 55.3% | 38.3% | 6.4% | 1998 |
| Concordia County | 42 | 45.2% | 45.2% | 9.5% | 1982 |
| St. John the Baptist County | 40 | 37.5% | 60% | 2.5% | 1979 |
| Plaquemines County (this page) | 34 | 17.6% | 61.8% | 20.6% | 1981 |
| St. James County | 26 | 30.8% | 61.5% | 7.7% | 1973 |
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 Plaquemines 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 Plaquemines County, both outside Louisiana so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside LA (34 bridges here).
- Bear Lake County, ID · 34 bridges
- Golden Valley County, ND · 34 bridges
- Guayanilla County, PR · 34 bridges
- Jayuya County, PR · 34 bridges
Similar average build year
Nearest mean year-built outside LA (1981 here).
- Franklin County, OH · avg 1981 · 922 bridges
- Greenville County, SC · avg 1981 · 635 bridges
- Montgomery County, OH · avg 1981 · 632 bridges
- McLean County, IL · avg 1981 · 624 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Good-condition bridges (6)
BELAIR PUMP RD
GoodOver: BELAIR PUMP STAION
0.5 MI EAST OF LA 39, Plaquemines, LA
Built 2014 Load: 33.7 t
Duvic Pump Rd
GoodOver: DRAIN CANAL
0.1 MI W OF LA 23, Plaquemines, LA
Built 2005 Load: 35.3 t
LA0406
GoodOver: INDUSTRY CANAL
3.11 MI NORTH OF LA 23, Plaquemines, LA
Built 1977 Load: 37.2 t ADT: 12,412
LA0406
GoodOver: PLANTERS CANAL
1.71 MI NORTH OF LA 23, Plaquemines, LA
Built 1977 Load: 40.8 t ADT: 12,412
MAGAZINE ROAD
GoodOver: BAYOU BARRIERE
BACK GATE, Plaquemines, LA
Built 1974 Load: 45.4 t ADT: 1,000
HERMITAGE RD
GoodOver: HERMITAGE BAYOU
5.05 MI. W. OF LA 23, Plaquemines, LA
Built 2013 Load: 73.9 t
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.