County profile · official public datasets

Jefferson County, IA

157 public highway bridges tracked in the FHWA National Bridge Inventory: 43.9% rated Good, 37.6% Fair, 18.5% Poor.

157
Public bridges
43.9%
Good condition
18.5%
Poor condition

The verdict

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

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

Top 47%
lowest Poor share in state
18.5%
Poor-condition share
157
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.

Jefferson County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Jefferson County ranks #47 of 99 Iowa counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 18.5%). Jefferson County, Iowa contains 157 public highway bridges. Roughly 43.9% are rated “Good,” 37.6% “Fair,” and 18.5% “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

157

Public highway bridges in Jefferson County

Good condition

43.9%

69 of 157 rated 7-9

Fair condition

37.6%

59 of 157 rated 5-6

Poor condition

18.5%

29 of 157 rated 4 or below

In-state Poor-share rank

#47 of 99

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

Condition distribution

Share of 157 NBI-tracked bridges by lowest applicable component rating.

Good
43.9% (69)
Fair
37.6% (59)
Poor
18.5% (29)

Jefferson County's Poor-condition bridges carry 4,683 vehicle crossings a day

That is 4% of the county's reported daily bridge traffic on 18.5% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 161 crossings a day against 1,060 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 157 of 157 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

39.5% of Jefferson County's bridges have passed the 50-year mark

62 of the 157 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 43.9% 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 44.8% of the county's Poor-condition bridge traffic

E BURLINGTON AVE over WEST CROW CREEK, built 1954, carries 2,100 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 29-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 4,683 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Jefferson County's bridges were built

157 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 2000s, when 30 of the county's bridges still in the inventory were built, which is 19.1% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year (1983) matches the Iowa average (1979).

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

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

The 5 Iowa counties nearest Jefferson County in number of bridges, with their condition splits. Its 18.5% Poor share is the 3rd-lowest of these 6. Its average build year of 1983 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 Jefferson County and the 5 Iowa counties closest to it in inventory size
County Bridges Poor
Wayne County 163 18.4%
Monona County 162 25.3%
Jefferson County (this page) 157 18.5%
Buena Vista County 156 31.4%
Van Buren County 156 31.4%
Clay County 151 9.9%

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

Similar inventory size

Nearest county inventories outside IA (157 bridges here).

Similar average build year

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

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

All bridges (157)

US 34 EB

Fair

Over: CROW CREEK

0.8 mi. E of Jct. Iowa 1, Jefferson, IA

Built 2007 Load: 39.2 t ADT: 2,600

US 34 WB

Fair

Over: MITCHELL CREEK

3.6 mi. W of Jct. IA 1, Jefferson, IA

Built 2008 Load: 40.6 t ADT: 2,485

LOCAL

Fair

Over: SOUTH WALNUT CREEK

073093302, Jefferson, IA

Built 1986 Load: 42.6 t ADT: 15

SPRUCE AVE

Fair

Over: ROCK BRANCH

073083101, Jefferson, IA

Built 1950 Load: 43.4 t ADT: 50

FM

Fair

Over: BRUSH CREEK

072091505, Jefferson, IA

Built 1988 Load: 44.4 t ADT: 200

US 34 WB

Fair

Over: CHURCH CREEK

2.3 mi. E of Jct. SR V63, Jefferson, IA

Built 2007 Load: 46.6 t ADT: 3,900

LOCAL

Fair

Over: STREAM

071102904, Jefferson, IA

Built 1968 Load: 53.2 t ADT: 60

FM

Fair

Over: CREEK

073081902, Jefferson, IA

Built 1950 Load: 55.6 t ADT: 50

FM

Fair

Over: CREEK

072081502, Jefferson, IA

Built 1971 Load: 99.9 t ADT: 330

LOCAL

Good

Over: BIG CEDAR RIVER

071093404, Jefferson, IA

Built 1984 Load: 16.8 t ADT: 34

LOCAL

Good

Over: BRANCH MITCHELL CREEK

072102801, Jefferson, IA

Built 1983 Load: 27.2 t ADT: 80

LOCAL

Good

Over: BRUSH CREEK

072082706, Jefferson, IA

Built 1987 Load: 30.8 t ADT: 30

US 34 EB

Good

Over: OLD US 34

3.9 mi. W of Jct. IA 1, Jefferson, IA

Built 2007 Load: 31.2 t ADT: 2,345

US 34 WB

Good

Over: OLD US 34

3.9 mi. W of Jct. Iowa #1, Jefferson, IA

Built 2007 Load: 31.2 t ADT: 2,345

ASH AVE

Good

Over: CEDAR CREEK

072111804, Jefferson, IA

Built 2014 Load: 32.4 t ADT: 90

ASH AVE

Good

Over: CREEK

072111906, Jefferson, IA

Built 2014 Load: 32.4 t ADT: 90

PEACH AVE

Good

Over: WALNUT CREEK

073092206, Jefferson, IA

Built 2019 Load: 32.4 t ADT: 71

KIRKWOOD STREET

Good

Over: DRAINAGE

072102508, Jefferson, IA

Built 1996 Load: 32.7 t ADT: 3,201

IA 904

Good

Over: BNSF RR

072103000, Jefferson, IA

Built 2011 Load: 32.7 t ADT: 460

US 34

Good

Over: EAST CROW CREEK

072093000, Jefferson, IA

Built 1998 Load: 32.7 t ADT: 2,100

PEPPERMINT BLVD

Good

Over: BRANCH TROY CREEK

071090305, Jefferson, IA

Built 2016 Load: 32.7 t ADT: 15

220TH ST

Good

Over: BR TROY CREEK

071090403, Jefferson, IA

Built 2018 Load: 32.7 t ADT: 80

FM

Good

Over: BRANCH CEDAR CREEK

071101004, Jefferson, IA

Built 1990 Load: 32.7 t ADT: 360

265TH ST

Good

Over: CREEK

071102605, Jefferson, IA

Built 2020 Load: 32.7 t ADT: 30

IVY AVE

Good

Over: CREEK

071102806, Jefferson, IA

Built 2016 Load: 32.7 t ADT: 20

EPISCIA AVE

Good

Over: CREEK

071111104, Jefferson, IA

Built 2019 Load: 32.7 t ADT: 15

ELM AVE

Good

Over: LICK CREEK

071112302, Jefferson, IA

Built 2019 Load: 32.7 t ADT: 11

FM

Good

Over: BRUSH CREEK

072090804, Jefferson, IA

Built 2000 Load: 32.7 t ADT: 1,270

PINE AVE

Good

Over: BRANCH OF BRUSH CREEK

072091506, Jefferson, IA

Built 2012 Load: 32.7 t ADT: 30

FM

Good

Over: CROW CREEK

072093105, Jefferson, IA

Built 1994 Load: 32.7 t ADT: 1,400

171ST BLVD

Good

Over: CREEK

072100703, Jefferson, IA

Built 2018 Load: 32.7 t ADT: 26

SPRUCE AVE

Good

Over: BURR OAK CREEK

073080602, Jefferson, IA

Built 1990 Load: 32.7 t ADT: 120

136TH ST

Good

Over: BR WALNUT CREEK

73081903, Jefferson, IA

Built 2018 Load: 32.7 t ADT: 40

REDWOOD AVE

Good

Over: BRANCH WALNUT CREEK

073091304, Jefferson, IA

Built 2020 Load: 32.7 t ADT: 26

OLIVE AVE

Good

Over: BR SOUTH WALNUT CREEK

073093307, Jefferson, IA

Built 2016 Load: 32.7 t ADT: 15

FM

Good

Over: SOUTH WALNUT CREEK

073093306, Jefferson, IA

Built 2006 Load: 32.7 t ADT: 1,030

JASMINE AVE

Good

Over: MIDDLE WALNUT CREEK

073101004, Jefferson, IA

Built 2011 Load: 32.7 t ADT: 170

105TH ST

Good

Over: CREEK

073110303, Jefferson, IA

Built 2018 Load: 32.7 t ADT: 11

ELM AVE

Good

Over: CREEK

073112302, Jefferson, IA

Built 2017 Load: 32.7 t ADT: 80

LIBERTYVILLE RD

Good

Over: US 34

1.6 mi. W of Jct. IA 1, Jefferson, IA

Built 2006 Load: 32.7 t ADT: 1,050

230TH ST

Good

Over: CREEK

071110202, Jefferson, IA

Built 2019 Load: 32.7 t ADT: 45

230TH ST

Good

Over: CREEK

071110402, Jefferson, IA

Built 2019 Load: 32.7 t ADT: 30

LOCAL

Good

Over: BRUSH CREEK

072082604, Jefferson, IA

Built 1981 Load: 33.0 t ADT: 80

US 34 WB

Good

Over: BIG CEDAR CREEK

1.6 MI W OF JCT. SR V-63, Jefferson, IA

Built 2006 Load: 33.5 t ADT: 3,900

MAHOGANY AVE

Good

Over: DRAINAGE

072090604, Jefferson, IA

Built 2017 Load: 34.0 t ADT: 70

175TH ST

Good

Over: CREEK

072100903, Jefferson, IA

Built 2022 Load: 34.7 t ADT: 90

H33 BROOKVILLE

Good

Over: BRANCH COON CREEK

072110303, Jefferson, IA

Built 2013 Load: 34.7 t ADT: 110

US 34

Good

Over: MITCHELL CREEK

072102800, Jefferson, IA

Built 2009 Load: 34.9 t ADT: 4,360

US 34 EB

Good

Over: IA 1

At Jct. Iowa 1, Jefferson, IA

Built 2007 Load: 36.4 t ADT: 2,195

OSAGE AVE

Good

Over: RELOC US 34

3.0 mi. E of Jct. IA #1, Jefferson, IA

Built 2007 Load: 36.7 t ADT: 1,280
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.