Sweet Grass County, MT

89 public highway bridges

Sweet Grass County Bridge Snapshot

Sweet Grass County, Montana contains 89 public highway bridges in the FHWA National Bridge Inventory. Roughly 21.3% are rated “Good,” 49.4% “Fair,” 5.6% “Poor,” and 5.6% are classified as structurally deficient — the federal designation for spans whose deck, superstructure, or substructure has been rated 4 or below on the 0–9 NBI scale. Structurally deficient does not mean unsafe to cross; it means the bridge is on the priority list for repair or replacement.

Inspections in MT are conducted by certified engineers from the state Department of Transportation on a 24-month cycle, and results are reported back to the FHWA each spring. The list below shows every NBI-tracked bridge in the county, sorted by inventory load rating. Use the “Sort by” controls to surface the lowest-rated spans first, and click any row for full inspection history, traffic counts, and condition trends.

Source: FHWA National Bridge Inventory. See methodology for full definitions.

89
Total Bridges
21.3%
Good
5.6%
Poor
5.6%
Structurally Deficient

Condition Distribution

Good
21.3% (19)
Fair
49.4% (44)
Poor
5.6% (5)
SD
5.6% (5)

All Bridges (89)

BOULDER RD

Fair

Over: MILLER CREEK 001

19M S MCLEOD, Sweet Grass, MT

Built 1965 Load: 30.8 t ADT: 156

BRIDGER CREEK RD

Fair

Over: BRIDGER CREEK 054

15M S GREYCLIFF, Sweet Grass, MT

Built 2004 Load: 30.8 t ADT: 100

OLD US 10

Fair

Over: SPRING CREEK 035

2M NW GREYCLIFF, Sweet Grass, MT

Built 1936 Load: 30.8 t ADT: 342

I 90

Fair

Over: LOWER DEER CREEK

0.6M W GREYCLIFF, Sweet Grass, MT

Built 1980 Load: 32.7 t ADT: 6,415

I 90

Fair

Over: WORK CREEK

3.7M W REED POINT, Sweet Grass, MT

Built 1972 Load: 32.7 t ADT: 10,706

OLD US 10

Fair

Over: DRY CREEK 004

6M NW GREYCLIFF, Sweet Grass, MT

Built 1937 Load: 32.7 t ADT: 553

BOULDER RD

Fair

Over: SPECULATOR CREEK 011

20M S MCLEOD, Sweet Grass, MT

Built 1965 Load: 33.5 t ADT: 156

US 191

Fair

Over: OTTER CREEK

4M S MELVILLE, Sweet Grass, MT

Built 2004 Load: 33.6 t ADT: 657

OTTER CREEK RD

Fair

Over: TEN MILE CREEK 009

11M SE MELVILLE, Sweet Grass, MT

Built 1977 Load: 34.4 t ADT: 133

SUSIE CREEK RD

Fair

Over: BOULDER RIVER 045

1M S MCLEOD, Sweet Grass, MT

Built 1960 Load: 34.4 t ADT: 100

US 191

Fair

Over: BIG TIMBER CREEK

2M N BIG TIMBER, Sweet Grass, MT

Built 1997 Load: 34.5 t ADT: 1,333

I 90

Fair

Over: UPPER DEER CREEK

2.5M W GREYCLIFF, Sweet Grass, MT

Built 1980 Load: 37.0 t ADT: 6,415

I 90

Fair

Over: UPPER DEER CREEK

2.5M W GREYCLIFF, Sweet Grass, MT

Built 1980 Load: 37.0 t ADT: 6,415

HOWIE RD

Fair

Over: DRAINAGE 021

3M NE BIG TIMBER, Sweet Grass, MT

Built 1923 Load: 38.1 t ADT: 163

I 90

Fair

Over: SPRING CREEK

1M NW GREYCLIFF, Sweet Grass, MT

Built 1980 Load: 52.6 t ADT: 12,830

DRY FORK ROAD

Good

Over: E. BOULDER RIVER

NO DATA ENTERED, Sweet Grass, MT

Built 2007 Load: 16.8 t ADT: 50

OLD US 10

Good

Over: UPPER DEER CREEK 005

4M NW GREYCLIFF, Sweet Grass, MT

Built 1975 Load: 18.1 t ADT: 553

I 90

Good

Over: CNTY RD 113-FRYER CREEK

4.3M E SPRINGDALE, Sweet Grass, MT

Built 1983 Load: 25.4 t ADT: 6,078

NO DATA ENTERED

Good

Over: PICKET PIN CREEK

NO DATA ENTERED, Sweet Grass, MT

Built 2010 Load: 26.9 t ADT: 40

SOURDOUGH RD

Good

Over: SWEET GRASS CREEK 027

13M NE BIG TIMBER, Sweet Grass, MT

Built 1997 Load: 29.0 t ADT: 100

LOWER SWEET GRASS

Good

Over: SWEET GRASS CREEK 039

10M E BIG TIMBER, Sweet Grass, MT

Built 1965 Load: 30.8 t ADT: 100

LOWER SWEET GRASS

Good

Over: E FK SWEET GRASS CR 01

14M NE BIG TIMBER, Sweet Grass, MT

Built 2012 Load: 31.1 t ADT: 15

MELVILLE ROAD

Good

Over: SWEET GRASS CREEK

11 M NW MELVILLE, Sweet Grass, MT

Built 2023 Load: 32.1 t ADT: 100

OLD BOULDER ROAD

Good

Over: BOULDER RIVER 029

EAST BIG TIMBER, Sweet Grass, MT

Built 2020 Load: 32.7 t ADT: 100

I 90

Good

Over: LOWER DEER CREEK

0.6M W GREYCLIFF, Sweet Grass, MT

Built 1980 Load: 32.7 t ADT: 6,415

E BOULDER RD

Good

Over: BOULDER RIVER 030

2M S MCLEOD, Sweet Grass, MT

Built 2002 Load: 32.7 t ADT: 100

BRIDGER CREEK ROAD

Good

Over: BRIDGER CREEK

9M SE GREYCLIFF, Sweet Grass, MT

Built 2022 Load: 33.6 t ADT: 100

HOWIE RD

Good

Over: OTTER CREEK

2M NE BIG TIMBER, Sweet Grass, MT

Built 2000 Load: 33.6 t ADT: 481

BRIDGER CREEK RD

Good

Over: BRIDGER CREEK

13.6M SE GREYCLIFF, Sweet Grass, MT

Built 2021 Load: 34.5 t ADT: 100

OTTER CREEK RD

Good

Over: SWEET GRASS CREEK 00

6M SE MELVILLE, Sweet Grass, MT

Built 2009 Load: 34.5 t ADT: 65

SWAMP CREEK RD

Good

Over: BIG TIMBER CREEK

4M N BIG TIMBER, Sweet Grass, MT

Built 2019 Load: 35.4 t ADT: 100

RAPELJE RD

Good

Over: SWEET GRASS CREEK

11M NE BIG TIMBER, Sweet Grass, MT

Built 1993 Load: 38.1 t ADT: 57

SWAMP CREEK RD

Good

Over: SWAMP CREEK

5.9M N BIG TIMBER, Sweet Grass, MT

Built 2020 Load: 39.0 t ADT: 100

DERBY GULCH ROAD

Good

Over: WEST BRIDGER CREEK

NO DATA ENTERED, Sweet Grass, MT

Built 2007 Load: 42.8 t ADT: 40

UPPER DEER CR RD

Poor

Over: UPPER DEER CREEK 028

6M SE BIG TIMBER, Sweet Grass, MT

Built 1975 Load: 4.5 t ADT: 100

BOINTER RD

Poor

Over: SWEET GRASS CREEK 044

9M SE BIG TIMBER, Sweet Grass, MT

Built 1970 Load: 20.8 t ADT: 100

S 91

Poor

Over: BOULDER RIVER OVERFLOW

BIG TIMBER, Sweet Grass, MT

Built 1937 Load: 31.8 t ADT: 2,120

US 191

Poor

Over: RYE CREEK

2M S MELVILLE, Sweet Grass, MT

Built 1947 Load: 33.6 t ADT: 657

MCLEOD MAIN ST

Structurally Deficient

Over: WEST BOULDER RIVER 025

MCLEOD, Sweet Grass, MT

Built 1912 Load: 8.2 t ADT: 100

Related

Data sourced from official U.S. government datasets. See our methodology for details. Retrieved and formatted by PlainBridges Editorial