State profile · Near national median SD

Montana bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in Montana — drawn straight from the FHWA National Bridge Inventory.

5,122
Public bridges
28.3%
Good condition
6.7%
Poor condition
6.7%
Structurally deficient

Total Bridges

5,122

Public highway bridges in Montana

Good Condition

28.3%

1,447 bridges rated 7-9

-21.7pp vs 50% benchmark

Poor Condition

6.7%

343 bridges rated 0-4

Structurally Deficient

6.7%

343 bridges flagged for repair priority

-0.3pp vs national avg 7.0%

Montana vs national bridge condition

Montana — Good condition share 28.3%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

Montana — Structurally deficient share 22.3%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Bridge inventory deck-condition mix — Montana (FHWA NBI)

Montana28.25068332682546%52.08902772354549%GoodFairPoorStructurally Deficient
Bridge inventory deck-condition mix — Montana (FHWA NBI)

Counties (56)

Beaverhead 217 Big Horn 136 Blaine 101 Broadwater 31 Carbon 77 Carter 39 Cascade 185 Chouteau 42 Custer 71 Daniels 32 Dawson 109 Deer Lodge 68 Fallon 35 Fergus 155 Flathead 195 Gallatin 207 Garfield 26 Glacier 68 Golden Valley 17 Granite 73 Hill 44 Jefferson 128 Judith Basin 48 Lake 111 Lewis and Clark 196 Liberty 11 Lincoln 190 Madison 84 McCone 44 Meagher 52 Mineral 152 Missoula 205 Musselshell 25 Park 124 Petroleum 26 Phillips 100 Pondera 96 Powder River 23 Powell 112 Prairie 46 Ravalli 149 Richland 96 Roosevelt 57 Rosebud 114 Sanders 116 Sheridan 66 Silver Bow 66 Stillwater 90 Sweet Grass 89 Teton 81 Toole 35 Treasure 26 Valley 103 Wheatland 26 Wibaux 24 Yellowstone 283

Montana vs nearby ranks

Adjacent states on the structurally deficient leaderboard (lower share = better)

States are ranked by share of bridges flagged structurally deficient — the FHWA classification for any span where deck, superstructure, or substructure carries a condition rating of 4 or below. Lower percentages indicate stronger maintenance funding and inspection follow-through. States here sit immediately above and below Montana on the same metric.

37

North Carolina

6.16% top marginal rate
Structure
Progressive
Burden @ $100K
$18,901

15

Hawaii

6.47% top marginal rate
Structure
Progressive
Burden @ $100K
$1,206
Selected

30

Montana

6.70% top marginal rate
Structure
Progressive
Burden @ $100K
$5,122

36

New York

6.90% top marginal rate
Structure
Progressive
Burden @ $100K
$19,132

21

Kentucky

7.06% top marginal rate
Structure
Progressive
Burden @ $100K
$14,554

Bridges Needing Most Attention in Montana

Six lowest-condition bridges in Montana, ranked by composite NBI rating. Each is inspected at least every 24 months.

HWY 91 N

Poor

Over: BIG HOLE RIVER 041

22M N DILLON, Beaverhead, MT

Built 1940 Load: 2.7 t ADT: 155

SLEEPY HOLLOW LN

Structurally Deficient

Over: PRICKLY PEAR CREEK

3 M S MONTANA CITY, Jefferson, MT

Built 2010 Load: 2.7 t ADT: 100

CARBINE RD

Poor

Over: PABLO CANAL 026

4M W PABLO, Lake, MT

Built 1986 Load: 2.7 t ADT: 100

BOY SCOUT RD

Poor

Over: CLEARWATER RIVER 082

2M NW SEELEY LAKE, Missoula, MT

Built 1938 Load: 2.7 t ADT: 100

ASHLEY LAKE RD

Poor

Over: PABLO FEEDER CANAL 045

5M NE ST IGNATIUS, Lake, MT

Built 1965 Load: 3.0 t ADT: 100

SHEEP CR RD

Structurally Deficient

Over: SHEEP CREEK 097

12M S CASCADE, Cascade, MT

Built 1950 Load: 3.6 t ADT: 68

All Bridges in Montana

I 90

Unknown

Over: SEP WORK CREEK ROAD

3.1M W REED POINT, Sweet Grass, MT

Built 1972 ADT: 100

I 90

Unknown

Over: SEP WORK CREEK ROAD

3.1M W REED POINT, Sweet Grass, MT

Built 1972 ADT: 100

I 90

Unknown

Over: SEP HUMP CREEK ROAD

1.2M W REED POINT, Sweet Grass, MT

Built 1963 ADT: 100

I 90

Unknown

Over: SEP HUMP CREEK ROAD

1.2M W REED POINT, Sweet Grass, MT

Built 1972 ADT: 100

OLD BOULDER RD

Unknown

Over: SEP I 90 008

1M E BIG TIMBER, Sweet Grass, MT

Built 1981 ADT: 4,913

DEHART TRAIL

Unknown

Over: INT DEHART I 90 007

7M SW BIG TIMBER, Sweet Grass, MT

Built 1981 ADT: 6,078

S 91

Unknown

Over: INT EAST BIG TIMBER I 90

2M E BIG TIMBER, Sweet Grass, MT

Built 1981 ADT: 4,913

MAIN BOULDER RD

Unknown

Over: SEP I 90

BIG TIMBER, Sweet Grass, MT

Built 1980 ADT: 4,913

I 15

Unknown

Over: SEP 9TH RD NE

3M N POWER, Teton, MT

Built 1972 ADT: 100

I 15

Unknown

Over: SEP 9TH RD NE

3M N POWER, Teton, MT

Built 1972 ADT: 100

I 15

Unknown

Over: INT MAIN ST

DUTTON, Teton, MT

Built 1976 ADT: 828

I 15

Unknown

Over: INT MAIN ST

DUTTON, Teton, MT

Built 1976 ADT: 828

20TH RD NE

Unknown

Over: SEP I 15 001

4M N DUTTON, Teton, MT

Built 1977 ADT: 1,681

24TH RD NE

Unknown

Over: INT COLLINS RD I 15 003

6M SE BRADY, Teton, MT

Built 1977 ADT: 1,704

S 431

Unknown

Over: INT POWER I 15

POWER, Teton, MT

Built 1972 ADT: 1,505

I 15

Unknown

Over: SEP COUNTY ROAD

1M S SHELBY, Toole, MT

Built 1976 ADT: 100

I 15

Unknown

Over: SEP COUNTY ROAD

1M S SHELBY, Toole, MT

Built 1976 ADT: 100

I 15

Unknown

Over: INT SHELBY-RR

SHELBY, Toole, MT

Built 1960 ADT: 3,840

I 15

Unknown

Over: INT SHELBY-RR

SHELBY, Toole, MT

Built 1960 ADT: 3,840

I 15

Unknown

Over: INT KEVIN HWY

KEVIN, Toole, MT

Built 1980 ADT: 346

I 15

Unknown

Over: INT KEVIN HWY

KEVIN, Toole, MT

Built 1964 ADT: 346

I 15

Unknown

Over: INT 1ST ST NE

SUNBURST, Toole, MT

Built 1977 ADT: 792

I 15

Unknown

Over: INT 1ST ST NE

SUNBURST, Toole, MT

Built 1961 ADT: 792

MCVEY-MCALPINE RD

Unknown

Over: INT MCVEY CO ROAD 006

3M SE SWEETGRASS, Toole, MT

Built 1977 ADT: 862

BRONKEN RD

Unknown

Over: INT BRONKEN RD I 15 003

5M N SHELBY, Toole, MT

Built 1964 ADT: 1,010

POTTER RD

Unknown

Over: INT POTTER RD I 15 004

6M S OILMONT, Toole, MT

Built 1980 ADT: 1,010

SWAYZE RD

Unknown

Over: INT SWAYZE ROAD I 15 002

4M SE SUNBURST, Toole, MT

Built 1971 ADT: 959

NUTTER LEASE RD

Unknown

Over: SEP I 15 008

4M N OILMONT, Toole, MT

Built 1971 ADT: 959

HELSA RD

Unknown

Over: SEP I 15 012

2M N OILMONT, Toole, MT

Built 1971 ADT: 959

GUS BLAZE RD

Unknown

Over: SEP GUS BLASE ROAD 011

3M S OILMONT, Toole, MT

Built 1980 ADT: 1,010

LINCOLN RD

Unknown

Over: INT MARIAS VALLEY RD 007

3M S SHELBY, Toole, MT

Built 1976 ADT: 1,375

MARIAS VALLEY RD

Unknown

Over: SEP I 15 010

7M S SHELBY, Toole, MT

Built 1976 ADT: 1,294

S 67

Unknown

Over: FRONT ST-RR

SHELBY, Toole, MT

Built 1938 ADT: 100

S 67

Unknown

Over: INT N SHELBY I 15

1M N SHELBY, Toole, MT

Built 1960 ADT: 1,014

S 214-3RD AVE

Unknown

Over: INT SWEETGRASS-I 15

SWEETGRASS, Toole, MT

Built 1964 ADT: 985

I 94

Unknown

Over: INT HYSHAM

14.9M E BIGHORN, Treasure, MT

Built 1964 ADT: 433

I 94

Unknown

Over: INT HYSHAM

14.9M E BIGHORN, Treasure, MT

Built 1976 ADT: 433

HAINES RANCH RD

Unknown

Over: SEP I 94 016

3M SE SANDERS, Treasure, MT

Built 1976 ADT: 2,067

TULLOCK RD

Unknown

Over: INT BIGHORN I 94 002

1M S BIGHORN, Treasure, MT

Built 1963 ADT: 2,554

SARPY CREEK RD

Unknown

Over: INT SARPY CREEK I 94

2M SW SANDERS, Treasure, MT

Built 1967 ADT: 2,489

I 94

Unknown

Over: INT CARLYLE RD

6M E WIBAUX, Wibaux, MT

Built 1974 ADT: 113

I 94

Unknown

Over: INT CARLYLE RD

6M E WIBAUX, Wibaux, MT

Built 1974 ADT: 113

FRONTAGE ROAD 044

Unknown

Over: INT ROCHLITZ I 94 001

5M W WIBAUX, Wibaux, MT

Built 1974 ADT: 4,320

S 7-LOG CABIN RD

Unknown

Over: INT E WIBAUX I 94

NORTHEAST WIBAUX, Wibaux, MT

Built 1962 ADT: 3,583

S 97

Unknown

Over: INT W WIBAUX-I 94

NW OF WIBAUX, Wibaux, MT

Built 1962 ADT: 1,912

I 90

Unknown

Over: INT W LAUREL-RR

LAUREL, Yellowstone, MT

Built 2019 ADT: 725

19TH AVE W

Unknown

Over: I-90

LAUREL, Yellowstone, MT

Built 2020 ADT: 18,639

I 90

Unknown

Over: SEP WOLD ROAD

1.9M W LAUREL, Yellowstone, MT

Built 1967 ADT: 590

I 90

Unknown

Over: SEP WOLD ROAD

1.9M W LAUREL, Yellowstone, MT

Built 1967 ADT: 590

I 90

Unknown

Over: INT LAUREL-P 4-RR

LAUREL, Yellowstone, MT

Built 1964 ADT: 13,578

Showing 551-600 of 5,122 bridges

Related

All states → | National rankings → | Understanding conditions → | SD bridges explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges Editorial.

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the FHWA National Bridge Inventory (NBI). A "structurally deficient" rating is a repair-priority signal, not a closure or unsafe-to-cross designation. Consult a qualified civil engineer before making decisions based on this data.

Understanding Bridge Conditions

How FHWA rates bridge condition on a 0-9 scale.

Check Your Daily Bridges

How to look up bridge condition data for bridges on your route.

Read our methodology — how this data is sourced, computed, and verified.