County profile · official public datasets

Montgomery County, IA

210 public highway bridges tracked in the FHWA National Bridge Inventory: 21% rated Good, 53.8% Fair, 25.2% Poor.

210
Public bridges
21%
Good condition
25.2%
Poor condition

The verdict

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

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

68th
of 99 on Poor share
25.2%
Poor-condition share
210
public highway bridges
1973
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.

Montgomery County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Montgomery County ranks #68 of 99 Iowa counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 25.2%). Montgomery County, Iowa contains 210 public highway bridges. Roughly 21% are rated “Good,” 53.8% “Fair,” and 25.2% “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

210

Public highway bridges in Montgomery County

Good condition

21%

44 of 210 rated 7-9

Fair condition

53.8%

113 of 210 rated 5-6

Poor condition

25.2%

53 of 210 rated 4 or below

In-state Poor-share rank

#68 of 99

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

Condition distribution

Share of 210 NBI-tracked bridges by lowest applicable component rating.

Good
21% (44)
Fair
53.8% (113)
Poor
25.2% (53)

Montgomery County's Poor-condition bridges carry 6,789 vehicle crossings a day

That is 7.2% of the county's reported daily bridge traffic on 25.2% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 128 crossings a day against 419 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 210 of 210 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

63.8% of Montgomery County's bridges have passed the 50-year mark

134 of the 210 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 21% 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 17.5% of the county's Poor-condition bridge traffic

OLD US 71 over BNSF RR, built 1929, carries 1,187 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 53-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 6,789 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Montgomery County's bridges were built

210 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1960s, when 51 of the county's bridges still in the inventory were built, which is 24.3% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1973, 6 years older than the Iowa average of 1979.

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

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

The 5 Iowa counties nearest Montgomery County in number of bridges, with their condition splits. Its 25.2% Poor share is the 6th-lowest of these 6. Its average build year of 1973 against a peer-group mean of 1982 is 9 years older.

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

Bridge inventory size and condition shares for Montgomery County and the 5 Iowa counties closest to it in inventory size
County Bridges Poor
Lee County 214 13.6%
Floyd County 213 14.6%
Howard County 210 22.9%
Montgomery County (this page) 210 25.2%
Shelby County 207 9.7%
Washington County 207 15.9%

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

Similar inventory size

Nearest county inventories outside IA (210 bridges here).

Similar average build year

Nearest mean year-built outside IA (1973 here).

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

All 210 Good 44 Fair 113 Poor 53

All bridges (210)

US 71

Fair

Over: FULTONS CREEK

3.4 mi. N of jct. US 34, Montgomery, IA

Built 1972 Load: 35.5 t ADT: 1,390

FM

Fair

Over: W NODAWAY RIVER

072362801, Montgomery, IA

Built 1987 Load: 36.6 t ADT: 338

FM

Fair

Over: TRIB OF W NODAWAY

072361602, Montgomery, IA

Built 1995 Load: 36.7 t ADT: 50

100TH ST

Fair

Over: DRAINAGE

073360605, Montgomery, IA

Built 1990 Load: 37.2 t ADT: 20

FM

Fair

Over: TARKIO CREEK

072370302, Montgomery, IA

Built 1988 Load: 38.8 t ADT: 270

FM

Fair

Over: WALNUT CREEK

072393310, Montgomery, IA

Built 1988 Load: 39.4 t ADT: 153

LOCAL ROAD

Fair

Over: BRANCH OF TARKIO CREEK

072373301, Montgomery, IA

Built 1992 Load: 40.5 t ADT: 11

CHESTNUT ST.

Fair

Over: COE CREEK

073380104, Montgomery, IA

Built 1996 Load: 45.4 t ADT: 79

US 34

Fair

Over: WEST TARKIO CREEK

0.5 MI E OF E JCT. SR H34, Montgomery, IA

Built 1964 Load: 49.1 t ADT: 3,990

FM

Fair

Over: CRABAPPLE CREEK

072392903, Montgomery, IA

Built 1994 Load: 50.0 t ADT: 436

LOCAL ROAD

Fair

Over: LOCAL STREAM

071380406, Montgomery, IA

Built 1996 Load: 99.9 t ADT: 20

FM

Fair

Over: STREAM

071383201, Montgomery, IA

Built 1970 Load: 99.9 t ADT: 170

FM

Fair

Over: WALNUT CREEK TRIB

071390404, Montgomery, IA

Built 1966 Load: 99.9 t ADT: 150

LOCAL ROAD

Good

Over: INDIAN CREEK

073392901, Montgomery, IA

Built 1977 Load: 21.0 t ADT: 20

M55 J AVE

Good

Over: NISHNABOTNA TRIB

073383502, Montgomery, IA

Built 2003 Load: 24.9 t ADT: 26

FM

Good

Over: TARKIO CREEK

073371101, Montgomery, IA

Built 2006 Load: 25.5 t ADT: 259

FM

Good

Over: TRIBUTARY TO NODAWAY

071362102, Montgomery, IA

Built 2010 Load: 27.8 t ADT: 79

US 71

Good

Over: SIN CREEK

4.5 mi. S of Jct. SR H-14, Montgomery, IA

Built 1970 Load: 31.3 t ADT: 1,390

EASTERN AVE

Good

Over: RED OAK CREEK

000000000, Montgomery, IA

Built 1980 Load: 31.8 t ADT: 649

BROAD AVE

Good

Over: BRANCH TARKIO CREEK

071370410, Montgomery, IA

Built 1983 Load: 31.8 t ADT: 527

G13 U AVE

Good

Over: WEST NODAWAY RIVER

073361002, Montgomery, IA

Built 2018 Load: 32.4 t ADT: 120

H54 265TH ST

Good

Over: WEST NODAWAY

071362803, Montgomery, IA

Built 2017 Load: 32.4 t ADT: 300

230TH ST

Good

Over: WALNUT CREEK

071390801, Montgomery, IA

Built 2019 Load: 32.4 t ADT: 15

M37 BOXELDER AVE

Good

Over: BNSF RR

072392804, Montgomery, IA

Built 2014 Load: 32.4 t ADT: 249

210TH ST

Good

Over: WALNUT CREEK

072393305, Montgomery, IA

Built 2019 Load: 32.4 t ADT: 30

H20 (150TH ST)

Good

Over: NISHNABOTNA RIVER

073383403, Montgomery, IA

Built 2013 Load: 32.4 t ADT: 159

SR N18 (T AVE)

Good

Over: TRIB W NODAWAY RIVER

071360406, Montgomery, IA

Built 2011 Load: 32.7 t ADT: 40

FM

Good

Over: NISHNABOTNA RIVER

072382913, Montgomery, IA

Built 2002 Load: 32.7 t ADT: 761

LOCAL

Good

Over: WALNUT CREEK

071393003, Montgomery, IA

Built 1978 Load: 32.8 t ADT: 20

FM-210TH STREET

Good

Over: MIDDLE NODAWAY RIVER

072363603, Montgomery, IA

Built 2004 Load: 33.3 t ADT: 100

LOCAL

Good

Over: CRAPABLE TREE

073393502, Montgomery, IA

Built 2000 Load: 33.7 t ADT: 5

US 34

Good

Over: WALNUT CREEK

3.4 MI. W OF JCT. IA 48, Montgomery, IA

Built 1964 Load: 34.5 t ADT: 3,730

LOCAL ROAD

Good

Over: BRANCH OF TARKIO CREEK

072373410, Montgomery, IA

Built 2003 Load: 35.6 t ADT: 1,404

US 71

Good

Over: LONGS BRANCH

1.8 MI. N OF N JCT SR H34, Montgomery, IA

Built 1970 Load: 36.4 t ADT: 1,390

NUCKOLS ST

Good

Over: RED OAK CREEK

000000000, Montgomery, IA

Built 2001 Load: 37.6 t ADT: 150

N18 T AVE

Good

Over: W NODAWAY RIVER

072363302, Montgomery, IA

Built 2015 Load: 37.9 t ADT: 29

FM

Good

Over: WALNUT CREEK

072391302, Montgomery, IA

Built 1988 Load: 38.2 t ADT: 61

LOCAL

Good

Over: TRIB SEVEN MILE

073362002, Montgomery, IA

Built 1999 Load: 38.2 t ADT: 20

FM

Good

Over: INDIAN CREEK

073393201, Montgomery, IA

Built 2010 Load: 38.2 t ADT: 20

FM

Good

Over: W NODAWAY RIVER

072360901, Montgomery, IA

Built 1999 Load: 38.5 t ADT: 60

FM

Good

Over: WEST NODAWAY

073363303, Montgomery, IA

Built 2003 Load: 39.9 t ADT: 71

FM

Good

Over: NISHNABOTNA RIVER

072382903, Montgomery, IA

Built 1997 Load: 40.1 t ADT: 2,231

FM

Good

Over: SEVEN MILE CREEK

073360801, Montgomery, IA

Built 2007 Load: 41.0 t ADT: 259

LOCAL

Good

Over: NISHNABOTNA TRIB

072380201, Montgomery, IA

Built 2003 Load: 41.4 t ADT: 40

250TH ST

Good

Over: WALNUT CREEK

071391903, Montgomery, IA

Built 2011 Load: 42.4 t ADT: 30

H20 140TH ST

Good

Over: SEVEN MILE CREEK

073362901, Montgomery, IA

Built 2022 Load: 42.4 t ADT: 29

100TH ST

Good

Over: DRAINAGE

073360505, Montgomery, IA

Built 2015 Load: 49.9 t ADT: 15

LOCAL ROAD

Good

Over: TARKIO CREEK

073372201, Montgomery, IA

Built 1996 Load: 50.3 t ADT: 34

IA 48

Good

Over: MORMAN BRANCH CREEK

3.8 MI. S OF U.S. 34, Montgomery, IA

Built 1987 Load: 52.2 t ADT: 2,000

M37 BOXELDER AVE

Good

Over: CRABAPPLE CREEK

072391604, Montgomery, IA

Built 2021 Load: 52.5 t ADT: 100

Read our methodology - how this data is sourced, computed, and verified.

Related

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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.