State profile · Below national median SD

Idaho bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in Idaho — drawn straight from the FHWA National Bridge Inventory.

1,742
Public bridges
33.3%
Good condition
5.5%
Poor condition
5.5%
Structurally deficient

Total Bridges

1,742

Public highway bridges in Idaho

Good Condition

33.3%

580 bridges rated 7-9

-16.7pp vs 50% benchmark

Poor Condition

5.5%

96 bridges rated 0-4

Structurally Deficient

5.5%

96 bridges flagged for repair priority

-1.5pp vs national avg 7.0%

Idaho vs national bridge condition

Idaho — Good condition share 33.3%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

Idaho — Structurally deficient share 18.4%
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 — Idaho (FHWA NBI)

Idaho33.295063145809415%55.166475315729045%GoodFairPoorStructurally Deficient
Bridge inventory deck-condition mix — Idaho (FHWA NBI)

Counties (44)

Ada 81 Adams 42 Bannock 25 Bear Lake 13 Benewah 15 Bingham 75 Blaine 39 Boise 41 Bonner 47 Bonneville 50 Boundary 52 Butte 14 Camas 26 Canyon 77 Caribou 12 Cassia 38 Clark 18 Clearwater 65 Custer 81 Elmore 45 Franklin 4 Fremont 46 Gem 16 Gooding 25 Idaho 130 Jefferson 55 Jerome 26 Kootenai 60 Latah 26 Lemhi 73 Lewis 6 Lincoln 16 Madison 27 Minidoka 19 Nez Perce 19 Oneida 2 Owyhee 20 Payette 9 Power 13 Shoshone 139 Teton 13 Twin Falls 35 Valley 82 Washington 25

Idaho 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 Idaho on the same metric.

20

Kansas

5.25% top marginal rate
Structure
Progressive
Burden @ $100K
$23,867

56

Wyoming

5.41% top marginal rate
Structure
Progressive
Burden @ $100K
$3,181
Selected

16

Idaho

5.51% top marginal rate
Structure
Progressive
Burden @ $100K
$1,742

28

Mississippi

5.92% top marginal rate
Structure
Progressive
Burden @ $100K
$16,823

45

South Carolina

6.10% top marginal rate
Structure
Progressive
Burden @ $100K
$5,396

Bridges Needing Most Attention in Idaho

Six lowest-condition bridges in Idaho, ranked by composite NBI rating. Each is inspected at least every 24 months.

STC 6774;TETON HWY

Poor

Over: S.FK.TETON RIVER

0.5 N. TETON, Fremont, ID

Built 1977 Load: 0.9 t ADT: 1,200

SWAMP ROAD

Poor

Over: CAMAS CREEK

1.5 S. 0.3 E. HILL CITY, Camas, ID

Built 1965 Load: 1.8 t ADT: 40

ROAD 50343

Poor

Over: LOGAN CREEK

NO DATA ENTERED, Valley, ID

Built 1980 Load: 2.6 t ADT: 50

VADNAIS LANE

Poor

Over: CAMAS CREEK

1.9 S. 0.6 E. KILGORE, Clark, ID

Built 1981 Load: 2.7 t ADT: 50

2701: NORTH MILNER

Poor

Over: Milner Gooding Canal

5.0 mi N of Hunt Rd, Jerome, ID

Built 1960 Load: 4.2 t ADT: 25

MIDDLE FORK ROAD

Structurally Deficient

Over: M.FK.WEISER RIVER

7.3 W 3.4 S DONNELLY, Adams, ID

Built 1957 Load: 4.5 t ADT: 70

All Bridges in Idaho

KINGS RD; N 500 E

Fair

Over: GREAT WESTERN CANAL

2.5 N. 0.7 W. FIRTH, Bingham, ID

Built 1976 Load: 16.3 t ADT: 90

STOCKER CREEK ROAD

Fair

Over: SILVER CREEK

0.2 N. 5.0 W. PICABO, Blaine, ID

Built 1977 Load: 16.3 t ADT: 60

STC6705;ST CLAIR

Fair

Over: W. BRANCH SAND CREEK

3.8 S. 1.9 E. IDAHO FALLS, Bonneville, ID

Built 1966 Load: 16.3 t ADT: 2,600

STC7456; E IONA RD

Fair

Over: SAND CREEK

2.0 W. IONA, Bonneville, ID

Built 1957 Load: 16.3 t ADT: 4,300

STC6724;65TH SOUTH

Fair

Over: GREAT WESTERN CANAL

3.6 S. 5.7 W.IDAHO FALLS, Bonneville, ID

Built 1951 Load: 16.3 t ADT: 110

STC 6699;W 17TH N

Fair

Over: GREAT WESTERN CANAL

1.4 N. 2.9 W. IDAHO FALLS, Bonneville, ID

Built 1940 Load: 16.3 t ADT: 640

STC 7136;BELLIN RD

Fair

Over: PORTER CANAL

1.1 S. 2.2 W. IDAHO FALLS, Bonneville, ID

Built 1963 Load: 16.3 t ADT: 3,400

W 33RD SOUTH

Fair

Over: PORTER CANAL

1.6 S. 3.5 W. IDAHO FALLS, Bonneville, ID

Built 1959 Load: 16.3 t ADT: 1,400

55TH EAST ROAD

Fair

Over: NORTH FORK WILLOW CREEK

3.2 N. IONA, Bonneville, ID

Built 1963 Load: 16.3 t ADT: 1,300

N 26TH W

Fair

Over: OSGOOD CANAL

3.88 NE OSGOOD, Bonneville, ID

Built 1928 Load: 16.3 t ADT: 20

STC 5805;WESTSIDE

Fair

Over: LONG CANYON CREEK

3.2 S. 1.8 W. PORTHILL, Boundary, ID

Built 1956 Load: 16.3 t ADT: 70

MACON FLAT ROAD

Fair

Over: CAMAS CREEK

0.3 S. 9.5 E. FAIRFIELD, Camas, ID

Built 1945 Load: 16.3 t ADT: 20

STP 8213;MIDDLETON

Fair

Over: CALDWELL HIGHLINE CANAL

4.0 S. 0.3 E. MIDDLETON, Canyon, ID

Built 1950 Load: 16.3 t ADT: 9,400

PARMA ROAD

Fair

Over: D LINE CANAL

2.4 N. 0.4 E. PARMA, Canyon, ID

Built 1971 Load: 16.3 t ADT: 90

WALKER LAKE ROAD

Fair

Over: HIGH LINE CANAL

1.3 N. 3.5 E. MARSING, Canyon, ID

Built 1967 Load: 16.3 t ADT: 90

BURDEN ROAD

Fair

Over: FARMERS COOP SEBREE CNL

0.8 N. 1.4 E. PARMA, Canyon, ID

Built 1977 Load: 16.3 t ADT: 360

NHS 3761;NORTHSIDE

Fair

Over: FIFTEEN MILE CREEK

3.2 S. 2.3 E. MIDDLETON, Canyon, ID

Built 1970 Load: 16.3 t ADT: 4,200

STC 8433;11TH AVE

Fair

Over: PHYLLIS CNL;11TH AVE EXT

IN NAMPA, Canyon, ID

Built 1994 Load: 16.3 t ADT: 5,000

STC7808;MIDDLETON

Fair

Over: WILLOW CREEK

1.3 N. 0.3 E. MIDDLETON, Canyon, ID

Built 1978 Load: 16.3 t ADT: 910

STC 7863;S.5TH AVE

Fair

Over: INDIAN CREEK

IN CALDWELL;S. 5TH AVE., Canyon, ID

Built 1935 Load: 16.3 t ADT: 2,900

KELLY TOPONCE ROAD

Fair

Over: RELIEF CHANNEL

3.9 N. 5.2 W. BANCROFT, Caribou, ID

Built 1964 Load: 16.3 t ADT: 160

SLUG CREEK RD

Fair

Over: BLACKFOOT RIVER

3.9 N. 7.3 E. CONDA, Caribou, ID

Built 1978 Load: 16.3 t ADT: 60

300 NORTH ROAD

Fair

Over: MAIN SOUTHSIDE CANAL

3.8N 1.2E DECLO;965E-300N, Cassia, ID

Built 1976 Load: 16.3 t ADT: 450

00 SOUTH ROAD

Fair

Over: MAIN SOUTHSIDE CANAL

0.8N 0.2W DECLO;830E-00S, Cassia, ID

Built 1972 Load: 16.3 t ADT: 100

500 SOUTH ROAD

Fair

Over: 'J' CANAL

5.3S 1.7W BURLEY;175W500S, Cassia, ID

Built 1970 Load: 16.3 t ADT: 100

HOUSTON ROAD

Fair

Over: BIG LOST RIVER

1.5 S. 1.5 E. MACKAY, Custer, ID

Built 1973 Load: 16.3 t ADT: 170

N 2700 E

Fair

Over: CROSSCUT CANAL

0.7 S. 3.2 E. ST ANTHONY, Fremont, ID

Built 1970 Load: 16.3 t ADT: 70

E 400 N

Fair

Over: INDEPENDENT CANAL

1.1 S. 1.4 W. PARKER, Fremont, ID

Built 1960 Load: 16.3 t ADT: 570

E 100 N

Fair

Over: CONSOLIDATED FARMERS CNL

4.3 S. 4.9 W. ST ANTHONY, Fremont, ID

Built 1976 Load: 16.3 t ADT: 80

N 2100 E

Fair

Over: ST. ANTHONY CANAL

1.1 N. 1.0 E. PARKER, Fremont, ID

Built 1961 Load: 16.3 t ADT: 150

E 800 N

Fair

Over: FALL RIVER CANAL

0.2 N. 2.6 E. CHESTER, Fremont, ID

Built 1976 Load: 16.3 t ADT: 50

STC 3842;STAR LANE

Fair

Over: FARMERS COOP CANAL

2.4 S. 3.3 W. EMMETT, Gem, ID

Built 1976 Load: 16.3 t ADT: 370

STC4715;CLEARCREEK

Fair

Over: CLEAR CREEK

6.4 S. 5.2 E. KOOSKIA, Idaho, ID

Built 1965 Load: 16.3 t ADT: 320

N 4950 E

Fair

Over: DRY BED SNAKE RIVER

1.0 N. 3.1 E. RIRIE, Jefferson, ID

Built 1968 Load: 16.3 t ADT: 550

2ND EAST STREET

Fair

Over: ANDERSON CANAL

IN RIRIE;2ND E.ST, Jefferson, ID

Built 1968 Load: 16.3 t ADT: 180

N 2375 E (CAL IDA)

Fair

Over: CAMAS CREEK;S.CAMAS BR

0.5 S. CAMAS, Jefferson, ID

Built 1972 Load: 16.3 t ADT: 40

250 WEST ROAD

Fair

Over: MILNER GOODING CANAL

4.4 N. 2.4 W. SHOSHONE, Lincoln, ID

Built 1975 Load: 16.3 t ADT: 50

N 3600 E

Fair

Over: COMBINED SNAKE RIVERS

5.1 S. 9.6 W. REXBURG, Madison, ID

Built 1968 Load: 16.3 t ADT: 270

STC 6760;N 3000 W

Fair

Over: S.FK.TETON R.;W.REXBURG

2.4 W. REXBURG, Madison, ID

Built 1977 Load: 16.3 t ADT: 640

N. 1ST EAST STREET

Fair

Over: REXBURG CANAL

IN REXBURG;N.1ST E.ST, Madison, ID

Built 1977 Load: 16.3 t ADT: 930

N 3RD E

Fair

Over: REXBURG CANAL

IN REXBURG;BARNEY DAIRY, Madison, ID

Built 1980 Load: 16.3 t ADT: 800

100 EAST ROAD

Fair

Over: 'A' CANAL

0.3 N. 1.0 E. RUPERT, Minidoka, ID

Built 1968 Load: 16.3 t ADT: 50

STC 7882;50 S. RD.

Fair

Over: 'B-4' CANAL

0.75 W. 0.5 S. RUPERT, Minidoka, ID

Built 1941 Load: 16.3 t ADT: 2,200

ELGIN ROAD

Fair

Over: DRAIN

3.3S 4.4E NEW PLYMOUTH, Payette, ID

Built 1965 Load: 16.3 t ADT: 90

SHOESTRING ROAD

Fair

Over: SNAKE RIVER;SW BLISS BR

0.6 S. 0.8 W. BLISS, Twin Falls, ID

Built 1977 Load: 16.3 t ADT: 180

CLOVER ROAD

Fair

Over: CEDAR DRAW

0.5 W. FILER;JORDEN COR, Twin Falls, ID

Built 1940 Load: 16.3 t ADT: 1,100

CUSTER MOTORWAY

Fair

Over: YANKEE FORK RIVER

NO DATA ENTERED, Custer, ID

Built 1961 Load: 16.5 t ADT: 100

FDR

Fair

Over: SALMON RIVER

7 MILES EAST STANLEY, Custer, ID

Built 1967 Load: 16.5 t ADT: 50

FOREST ROAD 468

Fair

Over: BARGAMIN CR

NO DATA ENTERED, Idaho, ID

Built 1954 Load: 16.5 t ADT: 40

FS ROUTE NO. 271

Fair

Over: BEAVER CREEK

BEAVER CREEK, Shoshone, ID

Built 1953 Load: 16.5 t ADT: 50

Showing 201-250 of 1,742 bridges

Related

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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.