State profile · Near median Poor share

Montana bridge safety

Condition ratings, load ratings, and Poor-condition data for every public highway bridge in Montana, based on the FHWA National Bridge Inventory.

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

Data updated May 2026

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 whose lowest applicable component is rated 0-4

-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 - Poor-condition share 22.3%
National avg

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

Montana vs nearby ranks

Adjacent states by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below Montana on the same metric.

NC

North Carolina

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

HI

Hawaii

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

MT

Montana

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

NY

New York

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

KY

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 the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

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

Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

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). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

Every figure on PlainBridge 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.