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

SH 69

Fair

Over: RAWSON CANAL

4.0 S. MERIDIAN, Ada, ID

Built 1990 Load: 35.4 t ADT: 32,000

SMA 7113; CURTIS

Fair

Over: SETTLERS CANAL

IN BOISE, Ada, ID

Built 2000 Load: 35.4 t ADT: 28,000

NOUNAN ROAD

Fair

Over: BEAR R;W.GEORGETOWN BR

1.4 S. 0.8 W. GEORGETOWN, Bear Lake, ID

Built 1974 Load: 35.4 t ADT: 180

SH 46

Fair

Over: SOLDIER CREEK

27.4 N. GOODING, Camas, ID

Built 1955 Load: 35.4 t ADT: 590

STC 3724;HOMEDALE

Fair

Over: GOLDEN GATE LOW LINE CNL

7.9 E. HOMEDALE, Canyon, ID

Built 1991 Load: 35.4 t ADT: 2,500

STC8317;LANSING RD

Fair

Over: CANYON CANAL

2.4 E. MIDDLETON, Canyon, ID

Built 2003 Load: 35.4 t ADT: 2,700

STC2739;ROCK CR RD

Fair

Over: ROCK CREEK;SHOE CR.BR.

19.2 S. HANSON, Cassia, ID

Built 1971 Load: 35.4 t ADT: 590

N 2750 E

Fair

Over: TETON RIVER

3.6 N. NEWDALE, Fremont, ID

Built 1976 Load: 35.4 t ADT: 290

I 90 EBL

Fair

Over: WOLF LODGE CREEK

10.4 E. COEUR D'ALENE, Kootenai, ID

Built 1960 Load: 35.4 t ADT: 7,250

IRON CREEK ROAD

Fair

Over: SALMON RIVER;IRON CK BR

20 S. SALMON, Lemhi, ID

Built 1965 Load: 35.4 t ADT: 50

SH 75

Fair

Over: BIG WOOD RIVER

17.9 N. SHOSHONE, Lincoln, ID

Built 1955 Load: 35.4 t ADT: 4,500

I 84 EBL

Fair

Over: 'B-4' CANAL

0.3 W. BURLEY, Minidoka, ID

Built 1966 Load: 35.4 t ADT: 11,000

SH 167

Fair

Over: GRANDVIEW IRRIG.DIST.CNL

IN GRANDVIEW, Owyhee, ID

Built 1970 Load: 35.4 t ADT: 1,800

STC 5764; MAIN ST

Fair

Over: PINE CREEK

AT PINEHURST WCL, Shoshone, ID

Built 1967 Load: 35.4 t ADT: 2,300

STC 3938;ROSEBERRY

Fair

Over: CASCADE RESERVOIR

1.3 S. 2.8 W. DONNELLY, Valley, ID

Built 1975 Load: 35.4 t ADT: 2,000

HIGHLINE ROAD

Fair

Over: BLACKFOOT CANAL

0.4 S. 0.2 W. FIRTH, Bingham, ID

Built 1971 Load: 36.0 t ADT: 400

2508: PARTRIDGE CR

Fair

Over: PARTRIDGE CREEK

Travel East on Big Salmon, Idaho, ID

Built 1990 Load: 36.0 t ADT: 4

STC 1821;BASELINE

Fair

Over: W BR SNAKE RVR VLY CANAL

1.0 S 0.1 W SHELLEY, Bingham, ID

Built 2001 Load: 36.3 t ADT: 2,000

SANDY ROAD

Fair

Over: NORTH CANAL

2.5 S. 1.2 W. BLACKFOOT, Bingham, ID

Built 1955 Load: 36.3 t ADT: 200

KIMBALL; N 400 E

Fair

Over: W BR SNAKE R VALLEY CNL

8.4 NE. BLACKFOOT, Bingham, ID

Built 1980 Load: 36.3 t ADT: 110

BUTTE ROUND ROAD

Fair

Over: DESERT DRAIN

6.3 W. 0.8 N SPRINGFIELD, Bingham, ID

Built 1979 Load: 36.3 t ADT: 150

FS ROUTE NO. 2545

Fair

Over: COW CREEK

COW CREEK, Boundary, ID

Built 1964 Load: 36.3 t ADT: 50

SH 46

Fair

Over: SOLDIER CREEK

27.8 N. GOODING, Camas, ID

Built 1955 Load: 36.3 t ADT: 590

B AVE

Fair

Over: S. FORK CLEARWATER

IN KOOSKIA;B AVE-FRONT ST, Idaho, ID

Built 1963 Load: 36.3 t ADT: 100

STC 4721;BRIDGE ST

Fair

Over: S.FK.CLEARWATER RIVER

IN STITES, Idaho, ID

Built 1961 Load: 36.3 t ADT: 760

I 86 WBL

Fair

Over: UPRR;IGO OVERPASS

6.0 E. AMERICAN FALLS, Power, ID

Built 1963 Load: 36.3 t ADT: 6,250

STC3895;YELLOWPINE

Fair

Over: TROUT CREEK

14 S. YELLOW PINE, Valley, ID

Built 1985 Load: 36.3 t ADT: 70

NO DATA ENTERED

Fair

Over: LICK CREEK

NO DATA ENTERED, Valley, ID

Built 1982 Load: 36.3 t ADT: 50

SH 71

Fair

Over: SPRING CREEK

0.8 W. CAMBRIDGE, Washington, ID

Built 1958 Load: 36.3 t ADT: 770

US 95

Fair

Over: SAGE CREEK

1.0 SW. MIDVALE SWCL, Washington, ID

Built 1964 Load: 36.3 t ADT: 4,300

US 95

Fair

Over: DRY CREEK

0.4 S. MIDVALE SWCL, Washington, ID

Built 1964 Load: 36.3 t ADT: 4,300

JACKSON ROAD

Fair

Over: MANN CREEK

7.4 N. 4.8 E. WEISER, Washington, ID

Built 1973 Load: 36.3 t ADT: 90

BEAVER-N. FK

Fair

Over: CAVE CREEK

27 MI FROM PIERCE ID, Clearwater, ID

Built 1963 Load: 36.6 t ADT: 100

CAMP GRD. RD. 221B

Fair

Over: SLATE CREEK

ROCKY BLUFF C.G., Idaho, ID

Built 1957 Load: 36.6 t ADT: 50

FDR 373

Fair

Over: NF SPRUCE CREEK

BRUSHY FK, Idaho, ID

Built 2008 Load: 36.6 t ADT: 50

FS ROUTE NO. 278

Fair

Over: NORTH GOLD CREEK

NORTH GOLD, Bonner, ID

Built 1983 Load: 36.9 t ADT: 50

FS ROUTE NO. 636

Fair

Over: GRASS CREEK

GRASS CREEK, Boundary, ID

Built 1973 Load: 36.9 t ADT: 50

NO DATA ENTERED

Fair

Over: ELDORADO CREEK

FAN CREEK BRIDGE, Idaho, ID

Built 1974 Load: 36.9 t ADT: 20

FOREST ROAD 492

Fair

Over: TWENTY MILE CREEK

NO DATA ENTERED, Idaho, ID

Built 1958 Load: 36.9 t ADT: 40

FS ROUTE NO. 208

Fair

Over: CDA RIVER

19.8 MI. FROM BABINS JCT., Shoshone, ID

Built 1966 Load: 36.9 t ADT: 40

STP3728;LAKE HAZEL

Fair

Over: RIDENBAUGH HIGH LINE CNL

3.7 N. 1.6 W. KUNA, Ada, ID

Built 1992 Load: 37.2 t ADT: 1,900

I 15 NBL

Fair

Over: PRIVATE RD.;MACHINE PASS

6.9 N. POCATELLO, Bannock, ID

Built 1959 Load: 37.2 t ADT: 14,250

US 89

Fair

Over: THOMAS FORK CREEK EAST

0.4 E. GENEVA, Bear Lake, ID

Built 1993 Load: 37.2 t ADT: 660

WEEDING LANE

Fair

Over: RESERVATION CANAL

4.0 S. FIRTH, Bingham, ID

Built 1985 Load: 37.2 t ADT: 220

NHS 6710;YORK RD

Fair

Over: SNAKE RIVER

2.9 S. IDAHO FALLS SCL, Bonneville, ID

Built 1963 Load: 37.2 t ADT: 6,300

STC 5806;RIVERSIDE

Fair

Over: DEEP CREEK

0.7N. 3.2W. BONNERS FERRY, Boundary, ID

Built 1975 Load: 37.2 t ADT: 360

STC 3763;MARKET RD

Fair

Over: FARMERS COOP SEBREE CNL

0.7 S. 3.2 E. PARMA, Canyon, ID

Built 1990 Load: 37.2 t ADT: 640

STC3717;FRIENDS RD

Fair

Over: GOLDEN GATE CANAL

1.1 S. 4.5 E. WILDER, Canyon, ID

Built 1967 Load: 37.2 t ADT: 480

150 EAST ROAD

Fair

Over: 'J' CANAL

6.7S 1.5E BURLEY;630S150E, Cassia, ID

Built 1996 Load: 37.2 t ADT: 100

I 84

Fair

Over: 'N' CANAL

0.8 E. JEROME, Jerome, ID

Built 1966 Load: 37.2 t ADT: 24,500

Showing 851-900 of 1,742 bridges

Related

All states → | National rankings → | Understanding conditions → | SD bridges explained →
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.