Total bridges
68
Public highway bridges in Assumption County
County profile · official public datasets
Assumption County, LA
68 public highway bridges tracked in the FHWA National Bridge Inventory: 48.5% rated Good, 41.2% Fair, 10.3% Poor.
- 68
- Public bridges
- 48.5%
- Good condition
- 10.3%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Assumption County posts a better-than-median Poor-condition share among rated counties in the state across rated county bridge inventory.
- Top 50%
- lowest Poor share in state
- 10.3%
- Poor-condition share
- 68
- public highway bridges
- 1984
- 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.
Assumption County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Assumption County ranks #32 of 64 Louisiana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 10.3%). Assumption County, Louisiana contains 68 public highway bridges. Roughly 48.5% are rated “Good,” 41.2% “Fair,” and 10.3% “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
48.5%
33 of 68 rated 7-9
Fair condition
41.2%
28 of 68 rated 5-6
Poor condition
10.3%
7 of 68 rated 4 or below
In-state Poor-share rank
#32 of 64
Among Louisiana counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 68 NBI-tracked bridges by lowest applicable component rating.
Good 48.5% (33)
Fair 41.2% (28)
Poor 10.3% (7)
Assumption County's Poor-condition bridges carry 11,901 vehicle crossings a day
That is 3.5% of the county's reported daily bridge traffic on 10.3% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,700 crossings a day against 6,620 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 68 of 68 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
33.8% of Assumption County's bridges have passed the 50-year mark
23 of the 68 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 48.5% 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 46.7% of the county's Poor-condition bridge traffic
LA0070 over PIERRE PASS, built 1967, carries 5,560 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 11,901 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Assumption County's bridges were built
68 bridges with a recorded construction year, grouped by decade
- 1950s 8
1950–1959
8 bridges
- 1960s 7
1960–1969
7 bridges
- 1970s
1970–1979
21 bridges
- 1980s 7
1980–1989
7 bridges
- 1990s
1990–1999
11 bridges
- 2000s 7
2000–2009
7 bridges
- 2010s 6
2010–2019
6 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1970s, when 21 of the county's bridges still in the inventory were built, which is 30.9% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1984) matches the Louisiana average (1982).
How Assumption County compares with Louisiana's closest counties by inventory size
The 5 Louisiana counties nearest Assumption County in number of bridges, with their condition splits. Its 10.3% Poor share is the 2nd-lowest of these 6. Its average build year of 1984 against a peer-group mean of 1979 is 5 years newer.
Showing the 5 closest of 63 Louisiana counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Iberville County | 80 | 33.8% | 51.3% | 15% | 1975 |
| West Baton Rouge County | 73 | 32.9% | 52.1% | 15.1% | 1969 |
| Catahoula County | 70 | 45.7% | 45.7% | 8.6% | 1984 |
| Assumption County (this page) | 68 | 48.5% | 41.2% | 10.3% | 1984 |
| Red River County | 63 | 22.2% | 47.6% | 30.2% | 1982 |
| Cameron County | 58 | 19% | 55.2% | 25.9% | 1985 |
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 Assumption 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 Assumption County, both outside Louisiana so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside LA (68 bridges here).
- Bent County, CO · 68 bridges
- Columbia County, GA · 68 bridges
- Talbot County, GA · 68 bridges
- Wilcox County, GA · 68 bridges
Similar average build year
Nearest mean year-built outside LA (1984 here).
- Hennepin County, MN · avg 1984 · 936 bridges
- Duval County, FL · avg 1984 · 831 bridges
- El Paso County, CO · avg 1984 · 686 bridges
- Bell County, TX · avg 1984 · 660 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (28)
US0090
FairOver: BAYOU BOEUF
ASSUMPTION PH LN US 90, Assumption, LA
Built 1998 Load: 17.8 t ADT: 10,035
Bayou Dr W
FairOver: BAYOU PIERRE PASS
PIERRE PART, Assumption, LA
Built 1988 Load: 19.4 t ADT: 2,520
LA0001
FairOver: CONCIENNE CANAL
LA0001, Assumption, LA
Built 1952 Load: 21.7 t ADT: 6,998
LA1010
FairOver: BAYOU LAFOURCHE
LA1010, Assumption, LA
Built 1954 Load: 21.8 t ADT: 143
LA0998
FairOver: BAYOU LAFOURCHE
LA0998, Assumption, LA
Built 1972 Load: 22.4 t ADT: 877
LA0070
FairOver: DRAIN
3.3 M NE of LA 1&LA 70, Assumption, LA
Built 1977 Load: 25.6 t ADT: 11,166
Bayou Dr
FairOver: LITTLE BAY
1.7 MI. N. OF PIERRE PART, Assumption, LA
Built 1984 Load: 26.9 t ADT: 1,056
US0090
FairOver: LA 662 Aligator Bayou
0.8 Mi. E. of Duhon Blvd, Assumption, LA
Built 1998 Load: 27.5 t ADT: 4,014
LA1008
FairOver: BAYOU LAFOURCHE
LA1008, Assumption, LA
Built 1952 Load: 28.1 t ADT: 3,279
LA0402
FairOver: BAYOU LAFOURCHE @ MUNSON
LA0402, Assumption, LA
Built 1976 Load: 28.5 t ADT: 551
US0090
FairOver: BAYOU BOEUF BR EXTENSION
JCT of US 90 & LA 662, Assumption, LA
Built 1998 Load: 28.8 t ADT: 10,035
LA0070
FairOver: Avoca Island Cutoff
5.7 MI N LA 1016-1, Assumption, LA
Built 1988 Load: 32.7 t ADT: 6,787
LA1011
FairOver: B. LAFOURCHE (SUPREME)
0.04 M SW of LA 1&LA 1011, Assumption, LA
Built 1975 Load: 35.4 t ADT: 382
LA1247
FairOver: BAYOU LAFOURCHE
LA0398, Assumption, LA
Built 1953 Load: 35.4 t ADT: 1,038
LA0308
FairOver: BAYOU VALANCE
0.20 MI N JCT LA 1011, Assumption, LA
Built 1982 Load: 37.2 t ADT: 4,729
LA0403
FairOver: BAYOU LAFOURCHE
0.01 Mi E of LA 1, Assumption, LA
Built 1972 Load: 37.2 t ADT: 347
LA0402
FairOver: BAYOU ST;VINCENT.
2.8 M SE of LA 1&LA 70, Assumption, LA
Built 1980 Load: 37.2 t ADT: 174
Bridge St
FairOver: BAYOU LAFOURCHE
PLATTENVILLE, Assumption, LA
Built 1984 Load: 38.1 t ADT: 480
LA0070
FairOver: GRAND BAYOU
LA0070, Assumption, LA
Built 1958 Load: 39.0 t ADT: 5,760
LA0996
FairOver: BAYOU CREAUX
LA0966, Assumption, LA
Built 1973 Load: 39.0 t ADT: 524
LA0996
FairOver: BRUSLY ST.MARTIN C.
LA0996, Assumption, LA
Built 1973 Load: 39.0 t ADT: 524
LA0070
FairOver: DRAIN
2.0 M NE of LA 1&LA 70, Assumption, LA
Built 1973 Load: 40.8 t ADT: 3,881
LA0070
FairOver: DRAIN
2.0 M NE of LA 1&LA 70, Assumption, LA
Built 1972 Load: 40.8 t ADT: 6,289
LA0070
FairOver: BAYOU LAFOURCHE
0.06 M E of LA 1&LA 70, Assumption, LA
Built 1977 Load: 42.6 t ADT: 3,881
LA0070
FairOver: BAYOU NAPOLEON
0.8 M SW of LA 3127, Assumption, LA
Built 1972 Load: 43.5 t ADT: 11,166
LA0398
FairOver: BAYOU MORGAN CITY
LA0398, Assumption, LA
Built 1969 Load: 43.5 t ADT: 2,115
LA0398
FairOver: BAYOU L OURSE
LA0398, Assumption, LA
Built 1969 Load: 43.5 t ADT: 2,115
LA0070-S
FairOver: BAYOU LAFOURCHE
0.04 M N of LA 1&LA 70-S, Assumption, LA
Built 1977 Load: 46.3 t ADT: 8,101
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.