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

MULLOWNEY LN

Fair

Over: RR

BILLINGS-MULLOWNEY LN, Yellowstone, MT

Built 2007 Load: 43.5 t ADT: 20,106

Route 284

Fair

Over: Canyon Ferry Spillway

14 mi E-NE of Helena MT, Lewis and Clark, MT

Built 1950 Load: 44.1 t ADT: 600

RD 36

Fair

Over: WOLF CR

MP 2.3 ON RD 36, Lincoln, MT

Built 1969 Load: 44.1 t ADT: 50

NO DATA ENTERED

Fair

Over: S FK FISH CREEK

FISH CR LOLO CR, Mineral, MT

Built 1973 Load: 44.1 t ADT: 50

US 2

Fair

Over: TWO MEDICINE IRR CANAL

7M W CUT BANK, Glacier, MT

Built 1942 Load: 44.5 t ADT: 2,056

US 287

Fair

Over: JEFFERSON RIVER

10M SW THREE FORKS, Jefferson, MT

Built 2001 Load: 44.5 t ADT: 1,204

IRR - US 93

Fair

Over: RR-FINLEY CREEK

14M N MISSOULA, Missoula, MT

Built 2009 Load: 44.5 t ADT: 8,184

US 2

Fair

Over: BEAVER CREEK

WEST EDGE OF SACO, Phillips, MT

Built 2003 Load: 44.5 t ADT: 1,250

CLARK ST

Fair

Over: COTTONWOOD CREEK 083

DEER LODGE-CLARK ST, Powell, MT

Built 2007 Load: 44.5 t ADT: 244

BOWMAN RD

Fair

Over: MILL CREEK 103

3M W WOODSIDE, Ravalli, MT

Built 1973 Load: 44.5 t ADT: 100

IRR BIA RTE 30

Fair

Over: MAIN CANAL

8.9 KM SW OF OSWEGO, Valley, MT

Built 1983 Load: 44.5 t ADT: 225

RD 431

Fair

Over: TWOMILE CREEK

TWOMILE CR, Mineral, MT

Built 1959 Load: 45.0 t ADT: 40

AFTERBAY ROAD

Fair

Over: BIGHORN RIVER

AT SPILLWAY OF YELLOWTAIL, Big Horn, MT

Built 1976 Load: 45.4 t ADT: 165

US 12

Fair

Over: DEEP CREEK

11M E TOWNSEND, Broadwater, MT

Built 2015 Load: 45.4 t ADT: 707

S 35

Fair

Over: MILL CREEK

1M E CRESTON, Flathead, MT

Built 1995 Load: 45.4 t ADT: 7,060

I 15

Fair

Over: BOULDER RIVER

1.2M S BASIN, Jefferson, MT

Built 1985 Load: 45.4 t ADT: 3,141

CATARACT CREEK RD

Fair

Over: CATARACT CREEK 036

3M N BASIN, Jefferson, MT

Built 1965 Load: 45.4 t ADT: 100

US 2

Fair

Over: BEAVER CREEK OVERFLOW

1M EAST SACO, Phillips, MT

Built 1987 Load: 45.4 t ADT: 1,210

8TH LN

Fair

Over: MILL COULEE CANAL 049

8M E FAIRFIELD, Cascade, MT

Built 1950 Load: 46.0 t ADT: 100

RD 36

Fair

Over: WOLF CR

WOLF CREEK MP 13.1, Lincoln, MT

Built 1980 Load: 46.0 t ADT: 40

US 87

Fair

Over: OTTER CREEK

4M SE BELT, Cascade, MT

Built 1959 Load: 46.3 t ADT: 1,078

US 87

Fair

Over: OTTER CREEK

6M SE BELT, Cascade, MT

Built 1959 Load: 46.3 t ADT: 1,078

S 43

Fair

Over: DEEP CREEK

10M NW WISE RIVER, Deer Lodge, MT

Built 2006 Load: 46.3 t ADT: 454

I 15

Fair

Over: BOULDER RIVER

2.5M S BASIN, Jefferson, MT

Built 1985 Load: 46.3 t ADT: 3,141

IRR BIA ROUTE 166

Fair

Over: REVAIS CREEK

4.0K SOUTH OF HWY 200, Sanders, MT

Built 2014 Load: 46.3 t ADT: 30

I 94

Fair

Over: BEAVER CREEK

N WIBAUX, Wibaux, MT

Built 1962 Load: 46.3 t ADT: 1,609

GRAND AVE

Fair

Over: BBWA CANAL

BILLINGS-GRAND AVE, Yellowstone, MT

Built 1981 Load: 46.3 t ADT: 14,360

RAT LAKE ROAD

Fair

Over: STORMCASTLE CREEK

JUST PAST STORM CASTLE CG, Gallatin, MT

Built 1954 Load: 46.7 t ADT: 50

EAST FK LOLO CR

Fair

Over: LOLO CREEK

EAST FK LOLO, Missoula, MT

Built 1946 Load: 47.0 t ADT: 50

S 467

Fair

Over: UPPER SEVEN MILE CREEK

2M W LINDSAY, Dawson, MT

Built 1986 Load: 47.1 t ADT: 48

BUTTELMAN RD

Fair

Over: WILLOW CREEK 061

4M S WILLOW CREEK, Gallatin, MT

Built 1923 Load: 47.1 t ADT: 100

US 87

Fair

Over: OTTER CREEK

7M SE BELT, Cascade, MT

Built 1959 Load: 47.2 t ADT: 1,078

TRAIL CREEK RD

Fair

Over: MIZPAH CREEK 086

27M SE MILES CITY, Custer, MT

Built 1981 Load: 47.2 t ADT: 56

COUNTY ROAD 303

Fair

Over: BOX ELDER CREEK 082

17M NE GLENDIVE, Dawson, MT

Built 2001 Load: 47.2 t ADT: 100

IRR - US 2

Fair

Over: GOAT UNDERPASS

1M SE ESSEX, Flathead, MT

Built 1981 Load: 47.2 t ADT: 1,929

N FORK RD

Fair

Over: BIG CREEK

17M SE POLEBRIDGE, Flathead, MT

Built 1980 Load: 47.2 t ADT: 431

US 2

Fair

Over: PORCUPINE CREEK

NASHUA, Valley, MT

Built 2006 Load: 47.2 t ADT: 1,504

S 24

Fair

Over: ROANWOOD CREEK

5M N OPHEIM, Valley, MT

Built 1957 Load: 47.2 t ADT: 31

I 15

Fair

Over: BIG SHEEP CREEK

0.6M S DELL, Beaverhead, MT

Built 1971 Load: 48.1 t ADT: 1,803

I 15

Fair

Over: BIG SHEEP CREEK

0.6M S DELL, Beaverhead, MT

Built 1971 Load: 48.1 t ADT: 1,803

COUNTY ROAD 330

Fair

Over: USBR MAIN CANAL 058

5M N SAVAGE, Richland, MT

Built 1980 Load: 48.1 t ADT: 21

S 24

Fair

Over: MILK RIVER

3M SE GLASGOW, Valley, MT

Built 1992 Load: 48.1 t ADT: 907

FRONTAGE ROAD 280

Fair

Over: BIG SHEEP CREEK 027

SE OF DELL, Beaverhead, MT

Built 1969 Load: 49.0 t ADT: 100

JUDY LN

Fair

Over: RUBY RIVER 026

W OF ALDER, Madison, MT

Built 1984 Load: 49.0 t ADT: 100

RED LODGE CR RD

Fair

Over: RED LODGE CREEK 012

11M SW BOYD, Carbon, MT

Built 2005 Load: 49.5 t ADT: 100

COUNTY ROAD 103

Fair

Over: TONGUE RIVER 054

3M NE DECKER, Big Horn, MT

Built 1976 Load: 49.9 t ADT: 331

NO DATA ENTERED

Fair

Over: N BRANCH MARTEN CREEK

MARTEN CREEK, Sanders, MT

Built 1967 Load: 49.9 t ADT: 20

I 94

Fair

Over: BEAVER CREEK

N WIBAUX, Wibaux, MT

Built 1974 Load: 49.9 t ADT: 1,792

LINE CREEK ROAD

Fair

Over: STORMCASTLE CREEK

OFF SQ___ CREEK ROAD, Gallatin, MT

Built 1948 Load: 50.5 t ADT: 50

I 90 FRONTAGE RD

Fair

Over: BIGHORN RIVER

1M E HARDIN, Big Horn, MT

Built 2007 Load: 50.8 t ADT: 1,537

Showing 3,151-3,200 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.