County profile · official public datasets

Pondera County, MT

96 public highway bridges tracked in the FHWA National Bridge Inventory: 51% rated Good, 44.8% Fair, 4.2% Poor.

96
Public bridges: 51%
Good condition: 4.2%
Poor condition

The verdict

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

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

Top 29%
lowest Poor share in state: 4.2%
Poor-condition share: 96
public highway bridges: 1975
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.

Pondera County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Pondera County ranks #16 of 56 Montana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 4.2%). Pondera County, Montana contains 96 public highway bridges. Roughly 51% are rated “Good,” 44.8% “Fair,” and 4.2% “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

Public highway bridges in Pondera County

Good condition

51%

49 of 96 rated 7-9

Fair condition

44.8%

43 of 96 rated 5-6

Poor condition

4.2%

4 of 96 rated 4 or below

In-state Poor-share rank

#16 of 56

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

Condition distribution

Share of 96 NBI-tracked bridges by lowest applicable component rating.

Good

51% (49)

Fair

44.8% (43)

Poor

4.2% (4)

Pondera County's Poor-condition bridges carry 1,742 vehicle crossings a day

That is 4.3% of the county's reported daily bridge traffic on 4.2% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 436 crossings a day against 511 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 96 of 96 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

63.5% of Pondera County's bridges have passed the 50-year mark

61 of the 96 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 51% 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 54.4% of the county's Poor-condition bridge traffic

IRR - US 89 over BLACKTAIL CREEK, built 1965, carries 947 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 4-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 1,742 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1930s

4
1950s

8
1960s

30
1970s

25
1980s

11
2000s

10
2010s

4
2020s

4

What this shows Construction peaked in the 1960s, when 30 of the county's bridges still in the inventory were built, which is 31.3% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1975) matches the Montana average (1977).

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

The 5 Montana counties nearest Pondera County in number of bridges, with their condition splits. Its 4.2% Poor share is the 3rd-lowest of these 6. Its average build year of 1975 against a peer-group mean of 1979 is in line with the group.

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

Bridge inventory size and condition shares for Pondera County and the 5 Montana counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Phillips County	101	13.9%	69.3%	16.8%	1972
Madison County	97	32%	56.7%	11.3%	1981
Richland County	97	28.9%	68%	3.1%	1988
Pondera County (this page)	96	51%	44.8%	4.2%	1975
Sweet Grass County	94	28.7%	66%	5.3%	1977
Stillwater County	92	30.4%	68.5%	1.1%	1977

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

Similar inventory size

Nearest county inventories outside MT (96 bridges here).

Del Norte County, CA · 96 bridges
Routt County, CO · 96 bridges
Blaine County, ID · 96 bridges
Clare County, MI · 96 bridges

Similar average build year

Nearest mean year-built outside MT (1975 here).

San Bernardino County, CA · avg 1975 · 1,422 bridges
Lane County, OR · avg 1975 · 1,010 bridges
Fulton County, GA · avg 1975 · 775 bridges
Westmoreland County, PA · avg 1975 · 620 bridges

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

All 96 Good 49 Fair 43 Poor 4

Good-condition bridges (49)

Sort:

Pondera County Bridge Snapshot

Condition distribution

Pondera County's Poor-condition bridges carry 1,742 vehicle crossings a day

63.5% of Pondera County's bridges have passed the 50-year mark

One structure carries 54.4% of the county's Poor-condition bridge traffic

How Pondera 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 (49)

MESSENGER ROAD

VALIER DUPUYER RD

BULLHEAD RD

OVERPASS RD

KELLY RD

S 365-BRADY RD

HEIGHTS RD

SOLLID RD

MIDWAY RD E

S 44

SKYVIEW RD S

I 15

CHURCH RD S

S 21

FRANCES HEIGHTS RD

PENDROY RD

OLD SHELBY RD

MESSENGER RD

PREPUTIN RD

US 89

MIDWAY RD E

MIDWAY RD W

US 89

DRY FORK RD

DRY FORK RD

S 21-S MAIN ST

MERIDIAN RD

BLUE SKY RD

IRR BIA RTE 1

I 15

I 15

I 15

I 15

US 89

S 44

S 44

IRR BIA RTE 110

DRY FORK RD

SWIFT DAM RD

PRICE RD S

DERBY DR

US 89

US 89

I 15

I 15

US 89

FRANCES HEIGHTS RD

US 89

BIA RTE 1

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