Total bridges
109
Public highway bridges in Dawson County
County profile · official public datasets
Dawson County, MT
109 public highway bridges tracked in the FHWA National Bridge Inventory: 8.3% rated Good, 85.3% Fair, 6.4% Poor.
- 109
- Public bridges
- 8.3%
- Good condition
- 6.4%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Dawson 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.
- 32nd
- of 56 on Poor share
- 6.4%
- Poor-condition share
- 109
- public highway bridges
- 1972
- 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.
Dawson County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Dawson County ranks #32 of 56 Montana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6.4%). Dawson County, Montana contains 109 public highway bridges. Roughly 8.3% are rated “Good,” 85.3% “Fair,” and 6.4% “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.
Good condition
8.3%
9 of 109 rated 7-9
Fair condition
85.3%
93 of 109 rated 5-6
Poor condition
6.4%
7 of 109 rated 4 or below
In-state Poor-share rank
#32 of 56
Among Montana counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 109 NBI-tracked bridges by lowest applicable component rating.
Good 8.3% (9)
Fair 85.3% (93)
Poor 6.4% (7)
Dawson County's Poor-condition bridges carry 4,698 vehicle crossings a day
That is 3.2% of the county's reported daily bridge traffic on 6.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 671 crossings a day against 313 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 109 of 109 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
57.8% of Dawson County's bridges have passed the 50-year mark
63 of the 109 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 8.3% 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 91% of the county's Poor-condition bridge traffic
I 94 over CLEAR CREEK, built 1973, carries 4,277 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 7-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 4,698 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Dawson County's bridges were built
109 bridges with a recorded construction year, grouped by decade
- 1920s 3
1920–1929
3 bridges
- 1930s 2
1930–1939
2 bridges
- 1940s 1
1940–1949
1 bridges
- 1950s 11
1950–1959
11 bridges
- 1960s
1960–1969
36 bridges
- 1970s
1970–1979
29 bridges
- 1980s
1980–1989
17 bridges
- 1990s 3
1990–1999
3 bridges
- 2000s 4
2000–2009
4 bridges
- 2010s 2
2010–2019
2 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1960s, when 36 of the county's bridges still in the inventory were built, which is 33% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1972, 5 years older than the Montana average of 1977.
How Dawson County compares with Montana's closest counties by inventory size
The 5 Montana counties nearest Dawson County in number of bridges, with their condition splits. Its 6.4% Poor share is the 3rd-lowest of these 6. Its average build year of 1972 against a peer-group mean of 1979 is 7 years older.
Showing the 5 closest of 55 Montana counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Lake County | 117 | 57.3% | 27.4% | 15.4% | 1995 |
| Rosebud County | 114 | 18.4% | 76.3% | 5.3% | 1973 |
| Powell County | 113 | 25.7% | 68.1% | 6.2% | 1981 |
| Dawson County (this page) | 109 | 8.3% | 85.3% | 6.4% | 1972 |
| Valley County | 104 | 10.6% | 76.9% | 12.5% | 1975 |
| Blaine County | 102 | 33.3% | 56.9% | 9.8% | 1969 |
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 Dawson 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 Dawson County, both outside Montana so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MT (109 bridges here).
- Mariposa County, CA · 109 bridges
- Boone County, IL · 109 bridges
- Gove County, KS · 109 bridges
- Hodgeman County, KS · 109 bridges
Similar average build year
Nearest mean year-built outside MT (1972 here).
- Santa Clara County, CA · avg 1972 · 964 bridges
- Madison County, AL · avg 1972 · 710 bridges
- Kern County, CA · avg 1972 · 668 bridges
- York County, PA · avg 1972 · 569 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
All bridges (109)
MARSH RD
GoodOver: CEDAR CREEK
13M S GLENDIVE, Dawson, MT
Built 2003 Load: 33.7 t ADT: 93
S 200
GoodOver: CORRAL CREEK
11 M NE CIRCLE, Dawson, MT
Built 2020 Load: 34.5 t ADT: 237
COUNTY ROAD 530
PoorOver: S FK BURNS CREEK 092
12M NW INTAKE, Dawson, MT
Built 1975 Load: 4.5 t ADT: 100
ROAD 238
PoorOver: CLEAR CREEK 027
19M W GLENDIVE, Dawson, MT
Built 1979 Load: 11.8 t ADT: 50
COUNTY ROAD 542
PoorOver: THIRTEEN MILE CR 061
5M NW INTAKE, Dawson, MT
Built 1964 Load: 16.3 t ADT: 100
I 94
PoorOver: CLEAR CREEK
10M SW GLENDIVE, Dawson, MT
Built 1973 Load: 32.7 t ADT: 4,277
PLEASANT VIEW RD
PoorOver: SEVEN MILE CREEK 025
3M W GLENDIVE, Dawson, MT
Built 1983 Load: 35.4 t ADT: 50
COUNTY ROAD 524
PoorOver: N FK THIRTEN MILE CR 091
9M NE BLOOMFIELD, Dawson, MT
Built 1983 Load: 36.3 t ADT: 100
ROAD 261
PoorOver: CRACKERBOX CREEK 043
16M SW GLENDIVE, Dawson, MT
Built 1997 Load: 99.9 t ADT: 21
Read our methodology - how this data is sourced, computed, and verified.
Related
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.