County profile · official public datasets

Brazoria County, TX

618 public highway bridges tracked in the FHWA National Bridge Inventory: 62.8% rated Good, 34.8% Fair, 2.4% Poor.

618
Public bridges: 62.8%
Good condition: 2.4%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Brazoria County pairs a higher-than-median Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

194th
of 247 on Poor share: 2.4%
Poor-condition share: 618
public highway bridges: 1990
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.

Brazoria County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Brazoria County ranks #194 of 247 Texas counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.4%). Brazoria County, Texas contains 618 public highway bridges. Roughly 62.8% are rated “Good,” 34.8% “Fair,” and 2.4% “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.

Total bridges

618

Public highway bridges in Brazoria County

Good condition

62.8%

388 of 618 rated 7-9

Fair condition

34.8%

215 of 618 rated 5-6

Poor condition

2.4%

15 of 618 rated 4 or below

In-state Poor-share rank

#194 of 247

Among Texas counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 618 NBI-tracked bridges by lowest applicable component rating.

Good

62.8% (388)

Fair

34.8% (215)

Poor

2.4% (15)

Brazoria County's Poor-condition bridges carry 22,940 vehicle crossings a day

That is 0.5% of the county's reported daily bridge traffic on 2.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,529 crossings a day against 8,130 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 618 of 618 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

22.2% of Brazoria County's bridges have passed the 50-year mark

137 of the 618 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 62.8% 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 28.3% of the county's Poor-condition bridge traffic

FM 523 over OYSTER CREEK, built 1954, carries 6,484 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 15-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 22,940 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

3
1930s

27
1940s

6
1950s

27
1960s

49
1970s

37
1980s

145
1990s

72
2000s

88
2010s

145
2020s

19

What this shows Construction peaked in the 1980s, when 145 of the county's bridges still in the inventory were built, which is 23.5% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1990, 10 years newer than the Texas average of 1980.

How Brazoria County compares with Texas's closest counties by inventory size

The 5 Texas counties nearest Brazoria County in number of bridges, with their condition splits. Its 2.4% Poor share is the 6th-lowest of these 6. Its average build year of 1990 against a peer-group mean of 1987 is in line with the group.

Showing the 5 closest of 246 Texas counties eligible for comparison.

Bridge inventory size and condition shares for Brazoria County and the 5 Texas counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
McLennan County	714	51.8%	46.2%	2%	1980
Montgomery County	710	69.2%	30.1%	0.7%	1998
Ellis County	691	53.3%	45.2%	1.6%	1987
Bell County	660	54.7%	45%	0.3%	1984
Brazoria County (this page)	618	62.8%	34.8%	2.4%	1990
Nueces County	528	55.5%	43.8%	0.8%	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 Brazoria 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 Brazoria County, both outside Texas so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside TX (618 bridges here).

Contra Costa County, CA · 618 bridges
Westmoreland County, PA · 620 bridges
Monroe County, NY · 615 bridges
Weld County, CO · 614 bridges

Similar average build year

Nearest mean year-built outside TX (1990 here).

Maricopa County, AZ · avg 1990 · 2,847 bridges
Fairfax County, VA · avg 1990 · 751 bridges
Guilford County, NC · avg 1990 · 736 bridges
Adams County, CO · avg 1990 · 535 bridges

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 618 Good 388 Fair 215 Poor 15

Good-condition bridges (388)

Sort:

Brazoria County Bridge Snapshot

Condition distribution

Brazoria County's Poor-condition bridges carry 22,940 vehicle crossings a day

22.2% of Brazoria County's bridges have passed the 50-year mark

One structure carries 28.3% of the county's Poor-condition bridge traffic

How Brazoria County compares with Texas's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Good-condition bridges (388)

SH 288 CONN SH36NB

SH 35

SH 35

SH 35

SH 35

FM 523

SH 35

SH 35

SH 35

SH 35

SH 36

SH 36

SH 36

SH 36

SH 6

SH 6

SH 6

SH 6

SH 6

SH 288

SH 288

SH 288

SH 288

SH 288

SH 288

SH 288

SH 288

SH 288

FM 523

FM 1459

FM 1462

FM 1462

FM 2234

TXARNG ACCESS RD

SH 288 BUS

SH 288 BUS

SH 288

SH 35

SH 35

SH 36

SH 6

SH 6

FM 523

FM 1301

SH 35

FM 1459

FM 1462

FM 2004

FM 2004

SH 35

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