Bridges in Montana

5,235Total Bridges

1,682Good

3,165Fair

388Poor

Bridge Conditions in Montana

Montana has 5,235 bridges tracked in the National Bridge Inventory. Of these, 388 (7%) are rated as poor condition — meaning at least one major component has significant deterioration. The average bridge in Montana is 48 years old.

Montana Bridge Facts

Total Bridges	5,235
Good Condition	1,682
Fair Condition	3,165
Poor Condition	388
Average Bridge Age	48 years
Longest Bridge	2437.0 ft

Longest Bridges in Montana

Koocanusa Bridge over Koocanusa Reservoir2437.0 ftFair US 87-mt 3-mt 200 over Missouri River-u5205-rr2121.4 ftFair US 89-mt 3-mt 200 over Missouri River-u5205-rr2092.2 ftFair I 94 over Yellowstone River2013.8 ftFair I 94 over Yellowstone River1973.8 ftFair

Counties in Montana

Beaverhead227 bridges24 poor Big Horn133 bridges5 poor Blaine102 bridges10 poor Broadwater37 bridges4 poor Carbon81 bridges4 poor Carter42 bridges2 poor Cascade185 bridges11 poor Chouteau43 bridges2 poor Custer71 bridges6 poor Daniels33 bridges4 poor Dawson109 bridges9 poor Deer Lodge67 bridges3 poor Fallon38 bridges2 poor Fergus158 bridges9 poor Flathead204 bridges9 poor Gallatin212 bridges12 poor Garfield26 bridges2 poor Glacier71 bridges3 poor Golden Valley17 bridges Granite73 bridges9 poor Hill46 bridges3 poor Jefferson136 bridges7 poor Judith Basin45 bridges7 poor Lake116 bridges13 poor Lewis and Clark204 bridges11 poor Liberty10 bridges Lincoln191 bridges29 poor Madison98 bridges7 poor McCone43 bridges4 poor Meagher53 bridges7 poor Mineral153 bridges17 poor Missoula206 bridges15 poor Musselshell28 bridges1 poor Park126 bridges13 poor Petroleum26 bridges4 poor Phillips101 bridges22 poor Pondera96 bridges4 poor Powder River23 bridges Powell113 bridges7 poor Prairie46 bridges5 poor Ravalli150 bridges12 poor Richland97 bridges4 poor Roosevelt57 bridges7 poor Rosebud112 bridges7 poor Sanders120 bridges10 poor Sheridan66 bridges3 poor Silver Bow70 bridges2 poor Stillwater92 bridges1 poor Sweet Grass94 bridges6 poor Teton82 bridges3 poor Toole35 bridges Treasure26 bridges4 poor Valley103 bridges11 poor Wheatland27 bridges4 poor Wibaux25 bridges1 poor Yellowstone290 bridges7 poor

Poor Condition Bridges in Montana

Bridge	County	Length	Traffic	Year
I 90 over Int Reserve Street	Missoula	194.9 ft	13,664	1966
I 90 over Clark Fork River	Granite	254.6 ft	13,081	1970
I 90 over Clark Fork River	Missoula	981.6 ft	9,168	1964
Montana AVE over U1025-rr	Yellowstone	1710.6 ft	8,576	1960
Montana AVE over U1024-25-rr	Yellowstone	1712.9 ft	8,576	1960
I 90 over Abandoned Rr	Gallatin	203.1 ft	8,575	1969
S 82 over Flathead River	Flathead	685.7 ft	8,310	1955
IRR - US 93 over Nine Pipe Reservoir	Lake	77.4 ft	8,158	1933
Lincoln RD over Int Lincoln-i 15	Lewis and Clark	206.0 ft	7,492	1962
I 90 EB over Rr	Powell	250.0 ft	5,992	1973
I 90 over Rr	Powell	264.8 ft	5,992	1973
US 2 over Big Cherry Creek	Lincoln	150.9 ft	5,295	1976
I 90 over Int W Garrison-rr	Powell	709.6 ft	5,232	1979
S 78 over Yellowstone River	Stillwater	575.8 ft	5,017	1957
I 94 over Clear Creek	Dawson	52.5 ft	4,317	1973
US 287 over South Willow Creek	Madison	39.0 ft	4,102	1934
I 90 over Sep Elizabeth LN	Mineral	445.9 ft	4,088	1965
I 90 over Clark Fork River	Mineral	806.8 ft	4,088	1965
Old HWY 312 over Yellowstone River 170	Yellowstone	1022.0 ft	4,005	1949
I 90 over Clark Fork River	Mineral	1091.9 ft	3,719	1984
IRR - US 2 over Milk River	Blaine	213.9 ft	3,311	1964
S Shiloh RD over Sep I 90	Yellowstone	457.0 ft	3,188	1959
US 89 over Int East Livingston I 90	Park	278.9 ft	2,910	1962
S 16 over Crane Creek	Richland	37.1 ft	2,821	1957
HWY 91 N over Beaverhead River 033	Beaverhead	149.6 ft	2,676	1946
US 191 Fh 42 over Teepee Creek	Gallatin	28.9 ft	2,605	1962
US 191 over Grayling Creek	Gallatin	46.6 ft	2,605	1962
Old US 10 over Big Ditch 051	Yellowstone	65.0 ft	2,489	1932
S 200 over Clark Fork River	Sanders	952.4 ft	2,482	1960
S 23 over Yellowstone River	Richland	1102.0 ft	2,438	1994
Lolo ST over Rattlesnake Creek 009	Missoula	94.2 ft	2,363	1966
US 2 over Lodge Creek	Blaine	94.2 ft	2,335	1942
US 2 over Irrigation-stockpass	Blaine	152.9 ft	2,335	1940
Main ST over Clark Fork River	Powell	134.8 ft	2,330	1949
US 87 over Otter Creek	Cascade	102.4 ft	2,314	1959
US 87 over Otter Creek	Cascade	103.0 ft	2,314	1959
US 87 over Otter Creek	Cascade	103.0 ft	2,314	1959
S 287 over Weber Irrigation Canal	Madison	26.9 ft	2,300	1950
S Main AVE over Mission Creek 052	Lake	33.1 ft	2,233	1929
IRR - US 2 over Rr	Flathead	361.9 ft	2,225	1956
S 7-main ST N over Sandstone Creek	Fallon	64.6 ft	2,209	1941
US 2 over Drainage	Blaine	39.0 ft	2,141	1940
US 2 over Drainage	Blaine	58.1 ft	2,141	1940
S 91 over Boulder River Overflow	Sweet Grass	25.6 ft	2,133	1937
US 2 over Kootenai River-rr	Lincoln	941.9 ft	2,104	1942
Third ST NE over Abandoned Rr-antelope CR	Wheatland	203.7 ft	2,063	1939
IRR - US 2 over Chelsea Creek	Roosevelt	37.4 ft	2,054	1960
Frontage Road 295 over Ten Mile Creek 071	Lewis and Clark	50.9 ft	1,929	1962
I 15 over Int Lima-bailey ST	Beaverhead	119.1 ft	1,863	1959
Mt 55 over Fish Creek	Jefferson	38.1 ft	1,858	1953
I 15 over Int Monida S 509	Beaverhead	118.1 ft	1,771	1959
Skalkaho HWY over Skalkaho Creek 053	Ravalli	78.1 ft	1,713	1941
S 37 Fh 57 over Tobacco River	Lincoln	305.8 ft	1,699	1971
Mullan RD over Irrigation Canal	Missoula	23.0 ft	1,635	1970
S 141 over Nevada Creek	Powell	57.7 ft	1,594	1936
S Cruse AVE over Pedestrian Underpass	Lewis and Clark	45.9 ft	1,548	1972
S 200 over Rr	Sanders	315.0 ft	1,537	1957
Bridge ST over Swan River 110	Flathead	120.1 ft	1,503	1911
IRR - US 2 over Drainage	Roosevelt	21.0 ft	1,452	1970
S 200 over Stockpass	Lewis and Clark	21.0 ft	1,432	1949
S 474 over Rr	Missoula	183.7 ft	1,397	1959
Sun River RD over Sep West Hill-i 15 127	Cascade	319.9 ft	1,364	1967
S 1 over Clark Fork	Granite	300.9 ft	1,354	1966
IRR - US 2 over Drainage	Phillips	44.3 ft	1,351	1973
W Dry Creek RD over Baker Creek	Gallatin	101.4 ft	1,287	1967
S 83 Fh 15 over Lost Creek	Lake	58.1 ft	1,246	1953
US 87 over Drainage	Fergus	57.7 ft	1,067	1939
Irr-us 2 over Unstable Slope	Flathead	259.8 ft	1,013	1981
IRR - US 89 over Blacktail Creek	Pondera	145.0 ft	1,012	1965
Mt HWY 2 over Rr 061	Jefferson	112.9 ft	1,001	1932
S 80-13th ST over Missouri River	Chouteau	708.0 ft	930	1962
S Frontage RD 011 over Dempsey Creek 059	Powell	64.0 ft	916	1930
US 89 Fh 32 over Belt Creek	Cascade	166.0 ft	833	1968
SR 117 over Missouri River Overflow	Valley	279.9 ft	818	1950
US 12 Fh 11 over Lolo Creek	Missoula	88.9 ft	799	1957
Victor Crossing W over Bitterroot River 020	Ravalli	89.9 ft	746	1984
Victor Crossing E over Bitterroot River 017	Ravalli	60.0 ft	746	1984
US 191 over S Fork American Fork	Wheatland	28.9 ft	706	1941
Kootenai River RD over Pipe Creek	Lincoln	71.9 ft	702	1987
S 56 Fh 5 over Bull River	Sanders	77.1 ft	692	1960
S 200 over Cemetery Coulee	McCone	58.4 ft	680	1939
S 200 over Drainage	McCone	86.6 ft	680	1939
S 200 over Drainage	McCone	76.4 ft	680	1939
US 191 over Rye Creek	Sweet Grass	57.7 ft	661	1947
US 191 over Fish Creek	Wheatland	113.8 ft	661	1942
US 191 over Missouri River	Fergus	697.8 ft	655	1959
S 37 Fh 57 over Cadette Creek	Lincoln	97.1 ft	612	1971
S 37 Fh 57 over Pinkham Creek	Lincoln	208.0 ft	612	1971
Mt HWY 91 over Rr	Beaverhead	143.0 ft	612	1936
Axtell Anceny RD over Gallatin River 084	Gallatin	142.1 ft	569	1919
Old HWY 87 over Two Leggins Canal 0	Big Horn	33.1 ft	564	1931
Poplar River RD over Poplar River 015	Roosevelt	104.7 ft	563	1985
S 21 over Int Midway I 15	Pondera	349.1 ft	540	1972
Quast LN over Surprise Ditch 060	Ravalli	27.9 ft	537	1918
Frntage Road 81020 over Cottonwood Creek 083	Custer	172.6 ft	507	1928
Frntage Road 81020 over Miles Creek 037	Custer	58.4 ft	507	1929
Frntage Road 81020 over Macks Creek 038	Custer	39.4 ft	507	1929
Old HWY 10 W over Williams Coulee 007	Prairie	77.4 ft	507	1930
Craig Frontage RD over Missouri River 054	Lewis and Clark	506.9 ft	484	1933
S 78 Fh 83 over Red Lodge Creek	Carbon	26.9 ft	481	1953