County profile · official public datasets

Fremont County, IA

179 public highway bridges tracked in the FHWA National Bridge Inventory: 33% rated Good, 47.5% Fair, 19.6% Poor.

179
Public bridges: 33%
Good condition: 19.6%
Poor condition

The verdict

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

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

52nd
of 99 on Poor share: 19.6%
Poor-condition share: 179
public highway bridges: 1977
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.

Fremont County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Fremont County ranks #52 of 99 Iowa counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 19.6%). Fremont County, Iowa contains 179 public highway bridges. Roughly 33% are rated “Good,” 47.5% “Fair,” and 19.6% “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.

Total bridges

179

Public highway bridges in Fremont County

Good condition

33%

59 of 179 rated 7-9

Fair condition

47.5%

85 of 179 rated 5-6

Poor condition

19.6%

35 of 179 rated 4 or below

In-state Poor-share rank

#52 of 99

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

Condition distribution

Share of 179 NBI-tracked bridges by lowest applicable component rating.

Good

33% (59)

Fair

47.5% (85)

Poor

19.6% (35)

Fremont County's Poor-condition bridges carry 3,680 vehicle crossings a day

That is 1.8% of the county's reported daily bridge traffic on 19.7% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 105 crossings a day against 1,619 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 178 of 179 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

48.6% of Fremont County's bridges have passed the 50-year mark

87 of the 179 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 33% 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 21% of the county's Poor-condition bridge traffic

370 AVENUE over E NISHNA RIVER OVERFLOW, built 1957, carries 771 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 35-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 3,680 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

2
1920s

3
1930s

1
1940s

3
1950s

29
1960s

30
1970s

34
1980s

32
1990s

16
2000s

12
2010s

10
2020s

7

What this shows Construction peaked in the 1970s, when 34 of the county's bridges still in the inventory were built, which is 19% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1977) matches the Iowa average (1979).

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

The 5 Iowa counties nearest Fremont County in number of bridges, with their condition splits. Its 19.6% Poor share is the 3rd-lowest of these 6. Its average build year of 1977 against a peer-group mean of 1980 is in line with the group.

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

Bridge inventory size and condition shares for Fremont County and the 5 Iowa counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Appanoose County	183	41%	27.9%	31.1%	1981
Keokuk County	183	34.4%	45.9%	19.7%	1980
Ida County	182	42.9%	40.7%	16.5%	1983
Wright County	182	35.2%	35.7%	29.1%	1979
Fremont County (this page)	179	33%	47.5%	19.6%	1977
Des Moines County	176	40.9%	42.6%	16.5%	1978

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

Similar inventory size

Nearest county inventories outside IA (179 bridges here).

Graham County, AZ · 179 bridges
Thomas County, GA · 179 bridges
Carroll County, IL · 179 bridges
Morris County, KS · 179 bridges

Similar average build year

Nearest mean year-built outside IA (1977 here).

San Diego County, CA · avg 1977 · 1,632 bridges
King County, WA · avg 1977 · 1,238 bridges
Riverside County, CA · avg 1977 · 1,117 bridges
Shelby County, TN · avg 1977 · 1,077 bridges

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

All 179 Good 59 Fair 85 Poor 35

All bridges (179)

Sort:

Fremont County Bridge Snapshot

Condition distribution

Fremont County's Poor-condition bridges carry 3,680 vehicle crossings a day

48.6% of Fremont County's bridges have passed the 50-year mark

One structure carries 21% of the county's Poor-condition bridge traffic

How Fremont 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 (179)

SB I-29

215 STREET

I 29 NB

250 STREET

NB I-29

330 AVENUE

250 STREET

250 STREET

200TH ST

120 STREET

BLUFF ROAD

300 STREET

310 STREET

200 STREET

210 STREET

300 AVENUE

300 AVENUE

BLUFF ROAD

BLUFF ROAD

I 29 SB

IA 2

IA 333

I 29 NB

NB I-29

SB I-29

WAUBONSIE AVENU

I 29 SB

IA 333

FM 370 AVENUE

190 STREET

I 29 SB

WB IA 2

EB IA 2

I 29 NB

IA 2

WESTERN AVENUE

IA 2

150 STREET

160 STREET

260 STREET

LOCAL

US 59

SR L 31

US 275

400 AVENUE

NB I-29

J40 MANTI ROAD

IA 2 EB

IA 2 WB

IA 2 EB

Related