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Every bridge in Sweet Grass County, Montana

Name: Every bridge in Sweet Grass County, Montana
Creator: Bridge Report Card
License: https://creativecommons.org/publicdomain/zero/1.0/

94 inventoried bridges, busiest first

United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled August 20, 2026

Sweet Grass County, Montana, has 94 bridges in the 2025 National Bridge Inventory: 30 rated good, 58 fair, and 6 poor (as of August 20, 2026).
This index lists every one of them, busiest first; each links to its own condition record.

Bridge	Built	Vehicles/day	Condition
I 90 over Spring Creek	1980	12,306	Fair
I 90 over Work Creek	1972	10,845	Fair
I 90 over Lower Deer Creek	1980	6,153	Fair
I 90 over Lower Deer Creek	1980	6,153	Good
I 90 over Upper Deer Creek	1980	6,153	Fair
I 90 over Upper Deer Creek	1980	6,153	Fair
I 90 over Cnty Rd 113-fryer Creek	1983	6,090	Good
I 90 over Cnty Rd 113-fryer Creek	1983	6,090	Fair
I 90 over Int Springdale	1981	6,090	Good
I 90 over Int Springdale	1981	6,090	Good
I 90 over Jarrett CR Farm Access	1981	6,090	Fair
I 90 over Jarrett CR Farm Access	1981	6,090	Good
I 90 over Sep County Road	1981	6,090	Fair
I 90 over Sep County Road	1981	6,090	Fair
I 90 over Bridger Creek	1972	5,423	Fair
I 90 over Bridger Creek	1972	5,423	Fair
I 90 over Greycliff Creek Rd	1972	5,423	Fair
I 90 over Greycliff Creek Rd	1972	5,423	Fair
I 90 over Int Bridger Creek	1972	5,423	Fair
I 90 over Int Bridger Creek	1972	5,423	Fair
I 90 over Int Greycliff	1972	5,423	Fair
I 90 over Int Greycliff	1972	5,423	Fair
I 90 over Sep Hump Creek Road	1963	5,423	Fair
I 90 over Sep Hump Creek Road	1972	5,423	Fair
I 90 over Sep Work Creek Road	1972	5,423	Fair
I 90 over Sep Work Creek Road	1972	5,423	Fair
I 90 over Boulder River	1980	4,977	Fair
I 90 over Boulder River	1980	4,977	Good
I 90 over Int West Big Timber	1981	4,977	Good
I 90 over Int West Big Timber	1981	4,977	Fair
S 91 over Boulder River	1938	2,133	Fair
S 91 over Boulder River Overflow	1937	2,133	Poor
S 91 over Int East Big Timber I 90	1981	2,133	Fair
US 191 over Yellowstone River	1938	1,699	Fair
US 191 over Big Timber Creek	1997	1,341	Fair
Main Boulder Rd over Sep I 90	1980	958	Fair
US 191 over Cayuse Creek	1947	661	Fair
US 191 over Otter Creek	2004	661	Fair
US 191 over Rye Creek	1947	661	Poor
US 191 over Sweet Grass Creek	1947	661	Fair
Old US 10 over Dry Creek 004	1937	556	Fair
Old US 10 over Upper Deer Creek 005	1975	556	Good
Main Boulder Rd over Boulder River	1975	529	Good
Main Boulder Rd over Boulder River	1950	529	Fair
Main Boulder Rd over West Boulder River	1976	529	Fair
Howie Rd over Big Timber Creek	2004	484	Fair
Howie Rd over Otter Creek	2000	484	Good
Old US 10 over Bridger Creek 040	1931	344	Fair
Old US 10 over Lower Deer Creek 006	1928	344	Fair
Old US 10 over Spring Creek 035	1936	344	Fair
Otter Creek Rd over Ten Mile Creek 009	1977	202	Fair
Howie Rd over Drainage 021	1923	164	Fair
Boulder Rd over Boulder River 002	1931	157	Fair
Boulder Rd over Boulder River 003	2017	157	Good
Boulder Rd over Miller Creek 001	1965	157	Fair
Boulder Rd over Speculator Creek 011	1965	157	Fair
N Yellowstone Trl over Yellowstone River 010	2000	129	Fair
Yellowstone Trail over Duck Creek	1980	129	Fair
Bointer Rd over Sweet Grass Creek 044	1970	100	Poor
Bridger Creek Rd over Bridger Creek	2021	100	Good
Bridger Creek Rd over Bridger Creek 054	2004	100	Fair
Bridger Creek Road over Bridger Creek	2022	100	Good
Dehart Trail over Int Dehart I 90 007	1981	100	Good
E Boulder Rd over Boulder River 030	2002	100	Good
E Boulder Rd over E Boulder River 031	1965	100	Fair
E Boulder Rd over E Boulder River 033	1969	100	Good
E Boulder Rd over E Boulder River 034	1971	100	Fair
E Boulder Road over E Boulder River	2024	100	Good
Lower Sweet Grass over Sweet Grass Creek 039	1965	100	Good
Lower Sweet Grass over Yellowstone River 038	1991	100	Fair
Mcleod Main St over West Boulder River 025	1912	100	Poor
Melville Rd over Sweet Grass Creek 01	1957	100	Fair
Melville Road over Sweet Grass Creek	2023	100	Good
Old Boulder Rd over Sep I 90 008	1981	100	Fair
Old Boulder Road over Boulder River 029	2020	100	Fair
Sourdough Rd over Sweet Grass Creek 027	1997	100	Fair
Susie Creek Rd over Boulder River 045	1960	100	Fair
Swamp Creek Rd over Big Timber Creek	2019	100	Good
Swamp Creek Rd over Swamp Creek	2020	100	Good
Terland Rd over Bridger Creek 053	1975	100	Fair
Upper Deer CR Rd over Upper Deer Creek 028	1975	100	Poor
Wheeler Creek Rd over Wheeler Creek	2007	100	Good
Work Creek Rd over Work Creek 050	1993	100	Fair
Glaston Rd over Otter Creek	2013	73	Good
Otter Creek Rd over Sweet Grass Creek 00	2009	73	Good
Rapelje Rd over Sweet Grass Creek	1993	57	Good
1-lane Road over W.fork Stillwater River	1964	50	Fair
Dry Fork Road over E. Boulder River	2007	50	Good
Derby Gulch Road over West Bridger Creek	2007	40	Good
No Data Entered over Picket Pin Creek	2010	40	Good
Old US 10 over Pump Creek 042	1932	29	Fair
Old US 10 over Work Creek 041	1932	29	Poor
Lower Sweet Grass over E Fk Sweet Grass CR 01	2012	15	Good
Lower Sweet Grass over Sweet Grass Creek 01	2017	15	Good

Source: FHWA National Bridge Inventory, 2025.

Sweet Grass County bridge conditions · Montana bridges by county.

Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.