County profile · official public datasets

Chouteau County, MT

42 public highway bridges tracked in the FHWA National Bridge Inventory: 54.8% rated Good, 38.1% Fair, 7.1% Poor.

42
Public bridges: 54.8%
Good condition: 7.1%
Poor condition

The verdict

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

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

36th
of 56 on Poor share: 7.1%
Poor-condition share: 42
public highway bridges: 1981
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.

Chouteau County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Chouteau County ranks #36 of 56 Montana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 7.1%). Chouteau County, Montana contains 42 public highway bridges. Roughly 54.8% are rated “Good,” 38.1% “Fair,” and 7.1% “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

Public highway bridges in Chouteau County

Good condition

54.8%

23 of 42 rated 7-9

Fair condition

38.1%

16 of 42 rated 5-6

Poor condition

7.1%

3 of 42 rated 4 or below

In-state Poor-share rank

#36 of 56

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

Condition distribution

Share of 42 NBI-tracked bridges by lowest applicable component rating.

Good

54.8% (23)

Fair

38.1% (16)

Poor

7.1% (3)

Chouteau County's Poor-condition bridges carry 1,124 vehicle crossings a day

That is 9.2% of the county's reported daily bridge traffic on 7.1% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 375 crossings a day against 259 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 42 of 42 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

40.5% of Chouteau County's bridges have passed the 50-year mark

17 of the 42 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 54.8% 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 82.2% of the county's Poor-condition bridge traffic

S 80-13TH ST over MISSOURI RIVER, built 1962, carries 924 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 3-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 1,124 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1930s

4
1940s

3
1950s

4
1960s

4
1970s

3
1980s

5
1990s

5
2000s

7
2010s

5
2020s

2

What this shows Construction peaked in the 2000s, when 7 of the county's bridges still in the inventory were built, which is 16.7% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year (1981) matches the Montana average (1977).

How Chouteau County compares with Montana's closest counties by inventory size

The 5 Montana counties nearest Chouteau County in number of bridges, with their condition splits. Its 7.1% Poor share is the 5th-lowest of these 6. Its average build year of 1981 against a peer-group mean of 1977 is in line with the group.

Showing the 5 closest of 55 Montana counties eligible for comparison.

Bridge inventory size and condition shares for Chouteau County and the 5 Montana counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Hill County	46	58.7%	34.8%	6.5%	1983
Prairie County	46	13%	80.4%	6.5%	1962
McCone County	44	11.4%	79.5%	9.1%	1967
Chouteau County (this page)	42	54.8%	38.1%	7.1%	1981
Carter County	41	31.7%	63.4%	4.9%	1985
Broadwater County	37	27%	67.6%	5.4%	1990

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

Similar inventory size

Nearest county inventories outside MT (42 bridges here).

Montgomery County, GA · 42 bridges
Lee County, KY · 42 bridges
Concordia County, LA · 42 bridges
Talbot County, MD · 42 bridges

Similar average build year

Nearest mean year-built outside MT (1981 here).

Franklin County, OH · avg 1981 · 922 bridges
Greenville County, SC · avg 1981 · 635 bridges
Montgomery County, OH · avg 1981 · 632 bridges
McLean County, IL · avg 1981 · 624 bridges

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

All 42 Good 23 Fair 16 Poor 3

Good-condition bridges (23)

Sort:

Chouteau County Bridge Snapshot

Condition distribution

Chouteau County's Poor-condition bridges carry 1,124 vehicle crossings a day

40.5% of Chouteau County's bridges have passed the 50-year mark

One structure carries 82.2% of the county's Poor-condition bridge traffic

How Chouteau County compares with Montana'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 (23)

UPPER HIGHWOOD CR

BOOTLEGGER TRAIL

GEYSER CUTOFF RD

US 87

BUCK BRIDGE RD

DENT BRIDGE RD

NFSR 8840

NFSR 8840

UPPER HIGHWOOD CR

GAP RD

LOWER MARIS RD

LOMA BRIDGE RD

NFSR 8841

UPPER HIGHWOOD CR

UPPER HIGHWOOD CR

IRR - US 87

STAGECOACH TRAIL

S 80

SHEPHERD X-ING RD

NFSR 8841

BROADWAY AVE

IRR BIA RTE 30

S 80

Related