County profile · official public datasets

Webster County, IA

190 public highway bridges tracked in the FHWA National Bridge Inventory: 45.8% rated Good, 28.9% Fair, 25.3% Poor.

190
Public bridges: 45.8%
Good condition: 25.3%
Poor condition

The verdict

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

Webster County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

69th
of 99 on Poor share: 25.3%
Poor-condition share: 190
public highway bridges: 1983
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.

Webster County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Webster County ranks #69 of 99 Iowa counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 25.3%). Webster County, Iowa contains 190 public highway bridges. Roughly 45.8% are rated “Good,” 28.9% “Fair,” and 25.3% “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.

Total bridges

190

Public highway bridges in Webster County

Good condition

45.8%

87 of 190 rated 7-9

Fair condition

28.9%

55 of 190 rated 5-6

Poor condition

25.3%

48 of 190 rated 4 or below

In-state Poor-share rank

#69 of 99

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

Condition distribution

Share of 190 NBI-tracked bridges by lowest applicable component rating.

Good

45.8% (87)

Fair

28.9% (55)

Poor

25.3% (48)

Webster County's Poor-condition bridges carry 71,986 vehicle crossings a day

That is 27.3% of the county's reported daily bridge traffic on 25.3% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 1,500 crossings a day against 1,340 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 190 of 190 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

33.2% of Webster County's bridges have passed the 50-year mark

63 of the 190 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 45.8% 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 13.7% of the county's Poor-condition bridge traffic

1ST AVE S over 21ST ST & RR, built 1968, carries 9,860 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 48-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 71,986 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

4
1910s

4
1920s

2
1930s

2
1940s

2
1950s

14
1960s

14
1970s

43
1980s

15
1990s

32
2000s

26
2010s

29
2020s

3

What this shows Construction peaked in the 1970s, when 43 of the county's bridges still in the inventory were built, which is 22.6% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1983) matches the Iowa average (1979).

How Webster County compares with Iowa's closest counties by inventory size

The 5 Iowa counties nearest Webster County in number of bridges, with their condition splits. Its 25.3% Poor share is the 3rd-lowest of these 6. Its average build year of 1983 against a peer-group mean of 1974 is 9 years newer.

Showing the 5 closest of 98 Iowa counties eligible for comparison.

Bridge inventory size and condition shares for Webster County and the 5 Iowa counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Page County	196	24%	43.9%	32.1%	1975
Lucas County	195	32.3%	34.4%	33.3%	1977
Wapello County	190	45.8%	39.5%	14.7%	1987
Webster County (this page)	190	45.8%	28.9%	25.3%	1983
Adams County	186	10.2%	45.2%	44.6%	1967
Osceola County	185	38.4%	53%	8.6%	1965

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 Webster 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 Webster County, both outside Iowa so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside IA (190 bridges here).

Clinton County, IL · 190 bridges
Bienville County, LA · 190 bridges
Lincoln County, MT · 190 bridges
Benton County, OR · 190 bridges

Similar average build year

Nearest mean year-built outside IA (1983 here).

Dallas County, TX · avg 1983 · 3,230 bridges
Bexar County, TX · avg 1983 · 2,342 bridges
Sedgwick County, KS · avg 1983 · 1,333 bridges
Will County, IL · avg 1983 · 649 bridges

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

All 190 Good 87 Fair 55 Poor 48

All bridges (190)

Sort:

Webster County Bridge Snapshot

Condition distribution

Webster County's Poor-condition bridges carry 71,986 vehicle crossings a day

33.2% of Webster County's bridges have passed the 50-year mark

One structure carries 13.7% of the county's Poor-condition bridge traffic

How Webster County compares with Iowa's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

All bridges (190)

FM

LOCAL

290TH ST

KENYON RD SB

290TH ST

LOCAL

2ND AVE S

FM

KENYON RD SB

2ND AVE S

FIRST AVE SW

FM

IA 144

IA 7

FM

WILLIAMS DRIVE

LOCAL

FM

FM

LOCAL

KENYON RD NB

WB US 20

EB US 20

FM

EB US 20

IA 175

US 169

HWY 20

FM

D20 200TH ST

D 36

D20 200TH ST

LOCAL

FM

FM

FM

FM

FM

FM

FM

FM

FM

FM

FM

FM

US 20 EB

FM

KENYON RD NB

LOCAL

SB US 169

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