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 15

Unknown

Over: SEP NEUMAN SCH RD

2M N VAUGHN, Cascade, MT

Built 1972 ADT: 100

I 15

Unknown

Over: SEP GUNDERSON RD

2M S POWER, Cascade, MT

Built 1972 ADT: 100

I 15

Unknown

Over: SEP GUNDERSON RD

2M S POWER, Cascade, MT

Built 1972 ADT: 100

I 315S

Unknown

Over: INT I 15

GREAT FALLS, Cascade, MT

Built 1967 ADT: 6,889

I 315S

Unknown

Over: FAU 5225-14TH ST SW

GREAT FALLS, Cascade, MT

Built 1967 ADT: 9,271

I 315S

Unknown

Over: FAU 5225-14TH ST SW

GREAT FALLS, Cascade, MT

Built 1967 ADT: 3,395

I 315 S

Unknown

Over: FAU 5225-14TH ST SW

GREAT FALLS, Cascade, MT

Built 1997 ADT: 9,271

ANDERSON RD

Unknown

Over: INT GORDON-I 15

6M NW VAUGHN, Cascade, MT

Built 1972 ADT: 2,000

OLD ULM CASCADE RD

Unknown

Over: SEP I 15

6M NE CASCADE, Cascade, MT

Built 1977 ADT: 4,847

OLD ULM CASCADE RD

Unknown

Over: SEP I 15

3M SW ULM, Cascade, MT

Built 1970 ADT: 2,424

FRONTAGE ROAD 614

Unknown

Over: INT SEP I 15

4M SW CASCADE, Cascade, MT

Built 1978 ADT: 2,189

FRONTAGE ROAD 615

Unknown

Over: INT CANYON-I 15

11M SW CASCADE, Cascade, MT

Built 1968 ADT: 2,224

34TH ST NW

Unknown

Over: SEP 34TH ST-I 15

1M W GREAT FALLS, Cascade, MT

Built 1967 ADT: 3,244

SUN RIVER RD

Unknown

Over: SEP WEST HILL-I 15 127

GREAT FALLS, Cascade, MT

Built 1967 ADT: 5,101

US 89

Unknown

Over: INT VAUGHN-I 15

VAUGHN, Cascade, MT

Built 1960 ADT: 4,297

US 87-MT 3-MT 200

Unknown

Over: MISSOURI RIVER-U5205-RR

GREAT FALLS-10TH AVE S, Cascade, MT

Built 1983 ADT: 5,718

US 89-MT 3-MT 200

Unknown

Over: MISSOURI RIVER-U5205-RR

GREAT FALLS-10TH AVE S, Cascade, MT

Built 1951 ADT: 5,718

SMELTER AVE

Unknown

Over: 15TH ST NE

BLACK EAGLE-SMELTER AVE, Cascade, MT

Built 1963 ADT: 11,678

CENTRAL AVE W

Unknown

Over: INT CENTRAL AVE W-I 15

GREAT FALLS-CENTRAL AVE W, Cascade, MT

Built 1967 ADT: 3,244

CENTRAL AVE W

Unknown

Over: GALT AVE-RR

GREAT FALLS-CENTRAL AVE W, Cascade, MT

Built 1967 ADT: 689

CENTRAL AVE W

Unknown

Over: GALT AVE-RR

GREAT FALLS-CENTRAL AVE W, Cascade, MT

Built 1967 ADT: 689

AIRPORT DR

Unknown

Over: INT GORE HILL-I 15

1M SW GREAT FALLS, Cascade, MT

Built 1967 ADT: 3,053

I 94

Unknown

Over: INT P-23 BROADUS

SE EDGE MILES CITY, Custer, MT

Built 2019 ADT: 1,894

I 94

Unknown

Over: INT P-23 BROADUS

SE EDGE MILES CITY, Custer, MT

Built 2020 ADT: 3,788

I 94

Unknown

Over: SEP CEMETERY RD

S EDGE MILES CITY, Custer, MT

Built 1961 ADT: 689

I 94

Unknown

Over: SEP CEMETERY RD

S EDGE MILES CITY, Custer, MT

Built 1974 ADT: 689

I 94

Unknown

Over: INT DIAMOND RING

21M NE MILES CITY, Custer, MT

Built 1971 ADT: 100

I 94

Unknown

Over: INT DIAMOND RING

21M NE MILES CITY, Custer, MT

Built 1971 ADT: 100

VALLEY DR E

Unknown

Over: INT SHIRLEY-I 94 006

10M NE MILES CITY, Custer, MT

Built 1984 ADT: 2,111

FRONTAGE ROAD 005

Unknown

Over: INT RADAR BASE-I 94 004

8M SW MILES CITY, Custer, MT

Built 1961 ADT: 2,323

FRONTAGE ROAD 201

Unknown

Over: INT MOON CREEK-I 94 005

10M SW MILES CITY, Custer, MT

Built 1962 ADT: 2,323

US 94

Unknown

Over: INT W MILES CITY-I 94

3M SW MILES CITY, Custer, MT

Built 1961 ADT: 2,285

US 94

Unknown

Over: TONGUE RIVER

SW EDGE MILES CITY, Custer, MT

Built 2007 ADT: 100

US 94

Unknown

Over: INT BAKER-I 94

2M NE MILES CITY, Custer, MT

Built 1974 ADT: 2,481

I 94

Unknown

Over: COUNTY ROAD 119

15M SW GLENDIVE, Dawson, MT

Built 1973 ADT: 100

I 94

Unknown

Over: COUNTY ROAD 119

15M SW GLENDIVE, Dawson, MT

Built 1973 ADT: 100

I 94

Unknown

Over: INT CRACKER BOX ROAD

12M SW GLENDIVE, Dawson, MT

Built 1973 ADT: 100

I 94

Unknown

Over: INT CRACKER BOX ROAD

12M SW GLENDIVE, Dawson, MT

Built 1973 ADT: 100

I 94

Unknown

Over: SEP ROAD 240

1M SW GLENDIVE, Dawson, MT

Built 1976 ADT: 100

I 94

Unknown

Over: SEP ROAD 240

1M SW GLENDIVE, Dawson, MT

Built 1976 ADT: 100

I 94

Unknown

Over: INT P 98-W GLENDIVE

SW GLENDIVE, Dawson, MT

Built 1969 ADT: 94

I 94

Unknown

Over: INT P 98-W GLENDIVE

SW GLENDIVE, Dawson, MT

Built 1969 ADT: 453

I 94

Unknown

Over: INT CIRCLE-RR-7M CR

W GLENDIVE, Dawson, MT

Built 1969 ADT: 1,719

I 94

Unknown

Over: INT CIRCLE-RR-7M CR

W GLENDIVE, Dawson, MT

Built 1969 ADT: 1,719

I 94

Unknown

Over: INT P 20-SIDNEY

NW GLENDIVE, Dawson, MT

Built 1969 ADT: 3,948

I 94

Unknown

Over: INT P 20-SIDNEY

NW GLENDIVE, Dawson, MT

Built 1969 ADT: 3,948

I 94

Unknown

Over: SEP COUNTY RD 300

3M E GLENDIVE, Dawson, MT

Built 1980 ADT: 114

I 94

Unknown

Over: SEP COUNTY RD 300

3M E GLENDIVE, Dawson, MT

Built 1980 ADT: 114

I 94

Unknown

Over: INT GRIFFITH CREEK

9M E GLENDIVE, Dawson, MT

Built 1979 ADT: 100

I 94

Unknown

Over: INT GRIFFITH CREEK

9M E GLENDIVE, Dawson, MT

Built 1979 ADT: 100

Showing 101-150 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.