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 SHEEP CAMP RD

3.7M W WHITEHALL, Jefferson, MT

Built 1966 ADT: 100

I 90 EASTBOUND

Unknown

Over: INT WHITEHALL

WHITEHALL, Jefferson, MT

Built 1966 ADT: 100

I 90 WESTBOUND

Unknown

Over: INT WHITEHALL

WHITEHALL, Jefferson, MT

Built 1966 ADT: 100

I 90 EASTBOUND

Unknown

Over: P 69

3.1M W CARDWELL, Jefferson, MT

Built 1968 ADT: 1,002

I 90 WESTBOUND

Unknown

Over: P 69

3.1M W CARDWELL, Jefferson, MT

Built 1968 ADT: 1,002

I 90

Unknown

Over: INT CARDWELL-S 359

CARDWELL, Jefferson, MT

Built 1968 ADT: 1,389

I 90

Unknown

Over: INT CARDWELL-S 359

CARDWELL, Jefferson, MT

Built 1968 ADT: 1,389

I 90

Unknown

Over: SEP COUNTY ROAD

7.4M E CARDWELL, Jefferson, MT

Built 1969 ADT: 100

HOMESTAKE PASS

Unknown

Over: INT HOMESTAKE-I 90 005

HOMESTAKE PASS, Jefferson, MT

Built 1966 ADT: 11,082

PAUL GULCH RD

Unknown

Over: SEP I 90 002

WHITEHALL, Jefferson, MT

Built 1966 ADT: 10,289

MILLIGAN CANYON RD

Unknown

Over: INT MILLIGAN-I 90 004

11M W CARDWELL, Jefferson, MT

Built 1969 ADT: 5,527

FRONTAGE ROAD 925

Unknown

Over: INT JEFF CITY-I 15 001

JEFFERSON CITY, Jefferson, MT

Built 1970 ADT: 2,501

S HILLS RD-HWY 282

Unknown

Over: I-15

1M N MONTANA CITY, Jefferson, MT

Built 1968 ADT: 5,736

S 69

Unknown

Over: INT BOULDER I 15

BOULDER, Jefferson, MT

Built 1973 ADT: 1,904

S 518

Unknown

Over: INT MONTANA CITY-I 15

MONTANA CITY, Jefferson, MT

Built 1968 ADT: 5,736

I 15

Unknown

Over: SEP SIERRA RD E

4M N HELENA, Lewis and Clark, MT

Built 1962 ADT: 3,264

I 15

Unknown

Over: SEP SIERRA RD E

4M N HELENA, Lewis and Clark, MT

Built 1962 ADT: 3,264

I 15

Unknown

Over: INT GATES OF THE MTNS

17M S WOLF CREEK, Lewis and Clark, MT

Built 1962 ADT: 431

I 15

Unknown

Over: INT GATES OF THE MTNS

17M S WOLF CREEK, Lewis and Clark, MT

Built 1962 ADT: 431

I 15

Unknown

Over: INT SEIBEN

10M S WOLF CREEK, Lewis and Clark, MT

Built 1962 ADT: 37

I 15

Unknown

Over: INT SEIBEN

10M S WOLF CREEK, Lewis and Clark, MT

Built 1962 ADT: 37

I 15

Unknown

Over: INT SPRING CREEK-RR

7M S WOLF CREEK, Lewis and Clark, MT

Built 1964 ADT: 30

I 15

Unknown

Over: INT SPRING CREEK-RR

7M S WOLF CREEK, Lewis and Clark, MT

Built 1964 ADT: 30

I 15

Unknown

Over: SEP LYONS CREEK ROAD

6M S WOLF CREEK, Lewis and Clark, MT

Built 1964 ADT: 100

I 15

Unknown

Over: SEP LYONS CREEK ROAD

6M S WOLF CREEK, Lewis and Clark, MT

Built 1964 ADT: 100

I 15

Unknown

Over: INT WOLF CREEK

WOLF CREEK, Lewis and Clark, MT

Built 1966 ADT: 421

I 15

Unknown

Over: INT WOLF CREEK

WOLF CREEK, Lewis and Clark, MT

Built 1966 ADT: 421

I 15

Unknown

Over: INT CRAIG

CRAIG, Lewis and Clark, MT

Built 1967 ADT: 773

I 15

Unknown

Over: INT CRAIG

CRAIG, Lewis and Clark, MT

Built 1967 ADT: 773

I 15

Unknown

Over: SEP MISSOURI RVR-CO RD

2M N CRAIG, Lewis and Clark, MT

Built 1967 ADT: 327

I 15

Unknown

Over: SEP MISSOURI RVR-CO RD

2M N CRAIG, Lewis and Clark, MT

Built 1967 ADT: 327

I 15

Unknown

Over: MISSOURI RVR-RR-LOCAL

5M N CRAIG, Lewis and Clark, MT

Built 1971 ADT: 327

I 15

Unknown

Over: MISSOURI RVR-RR-LOCAL

5M N CRAIG, Lewis and Clark, MT

Built 1971 ADT: 327

SADDLE DRIVE

Unknown

Over: S HELENA INT I 15 156

1M S HELENA, Lewis and Clark, MT

Built 2007 ADT: 7,626

S HOWIE ST

Unknown

Over: REEDERS ALLEY 001

HELENA-REEDERS ALLEY, Lewis and Clark, MT

Built 1881 ADT: 100

PROSPECT AVE-US 12

Unknown

Over: INT CAPITOL-I 15

HELENA-PROSPECT AVE, Lewis and Clark, MT

Built 1961 ADT: 7,626

PROSPECT AVE-US 12

Unknown

Over: INT CAPITOL-I 15

HELENA-PROSPECT AVE, Lewis and Clark, MT

Built 1961 ADT: 11,699

US 287

Unknown

Over: INT AUGUSTA I 15

1M NE WOLF CREEK, Lewis and Clark, MT

Built 1966 ADT: 2,522

LINCOLN RD

Unknown

Over: INT LINCOLN-I 15

10M N HELENA, Lewis and Clark, MT

Built 1962 ADT: 2,340

E CUSTER AVE

Unknown

Over: INT CUSTER AVE-I 15

HELENA-E CUSTER AVE, Lewis and Clark, MT

Built 2012 ADT: 6,190

CEDAR ST

Unknown

Over: INT CEDAR ST-I 15

HELENA-CEDAR ST, Lewis and Clark, MT

Built 2002 ADT: 9,322

US 2

Unknown

Over: MCKILLOP RD

2M W HAPPY`S INN, Lincoln, MT

Built 1960 ADT: 100

I 15

Unknown

Over: RR-HWY 91- DRAINAGE

6.8M S MELROSE, Madison, MT

Built 1974 ADT: 155

I 15

Unknown

Over: RR-HWY 91-DRAINAGE

6.8M S MELROSE, Madison, MT

Built 1974 ADT: 155

I 15

Unknown

Over: SEP MELROSE RD

1.9M S MELROSE, Madison, MT

Built 1973 ADT: 81

I 15

Unknown

Over: SEP MELROSE RD

1.9M S MELROSE, Madison, MT

Built 1973 ADT: 81

I 15

Unknown

Over: INT MELROSE-HWY 91

MELROSE, Madison, MT

Built 1973 ADT: 100

I 15

Unknown

Over: INT MELROSE-HWY 91

MELROSE, Madison, MT

Built 1973 ADT: 100

I 90

Unknown

Over: SEP LOCAL ROAD

1.9M E LOOKOUT PASS, Mineral, MT

Built 1973 ADT: 100

I 90

Unknown

Over: SEP LOCAL ROAD

5M E LOOKOUT PASS, Mineral, MT

Built 1973 ADT: 100

Showing 251-300 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.