County profile · official public datasets

Judith Basin County, MT

48 public highway bridges tracked in the FHWA National Bridge Inventory: 56.3% rated Good, 31.3% Fair, 12.5% Poor.

48
Public bridges: 56.3%
Good condition: 12.5%
Poor condition

The verdict

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

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

50th
of 56 on Poor share: 12.5%
Poor-condition share: 48
public highway bridges: 1979
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.

Judith Basin County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Judith Basin County ranks #50 of 56 Montana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 12.5%). Judith Basin County, Montana contains 48 public highway bridges. Roughly 56.3% are rated “Good,” 31.3% “Fair,” and 12.5% “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

Public highway bridges in Judith Basin County

Good condition

56.3%

27 of 48 rated 7-9

Fair condition

31.3%

15 of 48 rated 5-6

Poor condition

12.5%

6 of 48 rated 4 or below

In-state Poor-share rank

#50 of 56

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

Condition distribution

Share of 48 NBI-tracked bridges by lowest applicable component rating.

Good

56.3% (27)

Fair

31.3% (15)

Poor

12.5% (6)

Judith Basin County's Poor-condition bridges carry 340 vehicle crossings a day

That is 1% of the county's reported daily bridge traffic on 12.5% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 57 crossings a day against 1,039 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 48 of 48 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

50% of Judith Basin County's bridges have passed the 50-year mark

24 of the 48 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 56.3% 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 19.1% of the county's Poor-condition bridge traffic

NFSR #487 over S FK JUDITH RIVER, built 1958, carries 65 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 6-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 340 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

1
1930s

2
1940s

1
1950s

9
1960s

9
1970s

4
1980s

2
1990s

5
2000s

6
2010s

7
2020s

2

What this shows Construction peaked in the 1950s, when 9 of the county's bridges still in the inventory were built, which is 18.8% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year (1979) matches the Montana average (1977).

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

The 5 Montana counties nearest Judith Basin County in number of bridges, with their condition splits. Its 12.5% Poor share is the 6th-lowest of these 6. Its average build year of 1979 against a peer-group mean of 1975 is in line with the group.

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

Bridge inventory size and condition shares for Judith Basin County and the 5 Montana counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Meagher County	53	20.8%	69.8%	9.4%	1980
Judith Basin County (this page)	48	56.3%	31.3%	12.5%	1979
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	42	54.8%	38.1%	7.1%	1981

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

Similar inventory size

Nearest county inventories outside MT (48 bridges here).

Wakulla County, FL · 48 bridges
Evans County, GA · 48 bridges
Owyhee County, ID · 48 bridges
Carter County, MO · 48 bridges

Similar average build year

Nearest mean year-built outside MT (1979 here).

Pima County, AZ · avg 1979 · 1,150 bridges
Jefferson County, KY · avg 1979 · 662 bridges
Spartanburg County, SC · avg 1979 · 638 bridges
McPherson County, KS · avg 1979 · 586 bridges

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

All 48 Good 27 Fair 15 Poor 6

Good-condition bridges (27)

Sort:

Judith Basin County Bridge Snapshot

Condition distribution

Judith Basin County's Poor-condition bridges carry 340 vehicle crossings a day

50% of Judith Basin County's bridges have passed the 50-year mark

One structure carries 19.1% of the county's Poor-condition bridge traffic

How Judith Basin 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 (27)

NFSR 235

NFSR 235

NFSR #251

US 87

NFSR #251

ECHO RD

US 87

US 87

LOWER SAGE CR RD

S PEAK RD

JUDITH RIVER RD

US 87

STRAW RD

INDIAN BUTTE RD

SPENCER RD

US 87

US 87

DOUBLE G RD

ANTELOP CREEK RD

S 551

MICKS DR

ACKLEY LAKE RD

PIONEER RD

US 87

US 87

US 87

US 87

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