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

FS ROUTE NO. 1341

Good

Over: NO DATA ENTERED

BEAVER CREEK, Bonner, ID

Built 2007 Load: 27.2 t ADT: 40

N 5TH W

Good

Over: BURGESS CANAL

2.1 N. 4.0 W. UCON, Bonneville, ID

Built 1962 Load: 27.2 t ADT: 660

HELLROARING RIDGE

Good

Over: HELLROARING CREEK

HELLROARING CREEK XING, Boundary, ID

Built 2017 Load: 27.2 t ADT: 50

TOWN CIRCLE ROAD

Good

Over: SEBREE CANAL

2.7 S. 5.4 E. NOTUS, Canyon, ID

Built 1980 Load: 27.2 t ADT: 400

BLACKFOOT RIVER RD

Good

Over: BLACKFOOT RIVER

11.4N 2.5E SODA SPRINGS, Caribou, ID

Built 1980 Load: 27.2 t ADT: 600

NO DATA ENTERED

Good

Over: INDIAN CREEK

NO DATA ENTERED, Idaho, ID

Built 2011 Load: 27.2 t ADT: 100

FS ROUTE NO. 218

Good

Over: SIMMONS CREEK

1 MI F/JCT FS RT 218 & 50, Shoshone, ID

Built 1935 Load: 27.2 t ADT: 50

FS ROUTE 509

Good

Over: EAST FORK BLUFF CREEK

EAST FORK BLUFF CREEK, Shoshone, ID

Built 2006 Load: 27.2 t ADT: 40

2300 EAST ROAD

Good

Over: SALMON CANAL LATERAL #2

0.7 N. 1.0 W. HOLLISTER, Twin Falls, ID

Built 1983 Load: 27.2 t ADT: 20

LICK CREEK ROAD

Good

Over: N. FK. LICK CREEK

14.5 E 10.5 N MCCALL, Valley, ID

Built 2009 Load: 27.2 t ADT: 40

N. CRANE ROAD

Good

Over: GRANGER CREEK

3.5 S. 11.8 E. MIDVALE, Washington, ID

Built 1996 Load: 27.2 t ADT: 60

SMA 7143;USTICK RD

Good

Over: NORTH SLOUGH

IN BOISE, Ada, ID

Built 2014 Load: 27.5 t ADT: 16,000

W. WILLOW-BIG OWL

Good

Over: CROOKED RIVER

2 MI E. OF EDNA CREEK CG, Boise, ID

Built 1971 Load: 27.5 t ADT: 15

OKEEFE CREEK ROAD

Good

Over: CLEAR CREEK

9 MI NNE OF LOWMAN, ID, Boise, ID

Built 1966 Load: 27.5 t ADT: 10

FOREST ROUTE 311

Good

Over: BIG CREEK

BIG CREEK DRAINAGE, Idaho, ID

Built 2019 Load: 27.5 t ADT: 50

FS ROUTE NO. 3325

Good

Over: GLOVER CREEK

GLOVER CREEK, Shoshone, ID

Built 1978 Load: 27.5 t ADT: 40

CLEAR CREEK ROAD

Good

Over: STONEY MEADOW CREEK

14 MI SW OF WARM LAKE, Valley, ID

Built 1963 Load: 27.5 t ADT: 12

NO DATA ENTERED

Good

Over: GOOSE CREEK

NO DATA ENTERED, Adams, ID

Built 1963 Load: 27.9 t ADT: 50

FS ROUTE NO. 2549

Good

Over: SKIN CREEK

SKIN CREEK, Boundary, ID

Built 1957 Load: 27.9 t ADT: 40

FROST ROAD

Good

Over: LOW LINE CANAL

5.2 S. 5.5 E. WILDER, Canyon, ID

Built 1990 Load: 27.9 t ADT: 50

NO DATA ENTERED

Good

Over: N F CLEARWATER RIVE

AQUARIOUS BRIDGE, Clearwater, ID

Built 1965 Load: 27.9 t ADT: 145

NO DATA ENTERED

Good

Over: SILVER CREEK

26 MILES NNW OF CHALLIS, Lemhi, ID

Built 1994 Load: 27.9 t ADT: 5

HAYDEN CR. ROAD

Good

Over: HAYDEN CREEK

NO DATA ENTERED, Lemhi, ID

Built 1974 Load: 27.9 t ADT: 10

4002: HUNTER-TRAPP

Good

Over: East Fork Pine Creek

5.6 mi S of I90, Shoshone, ID

Built 1998 Load: 27.9 t ADT: 25

SAMBO ROAD

Good

Over: NORTH CANAL

2.8 S. 1.2 W. BLACKFOOT, Bingham, ID

Built 1984 Load: 28.1 t ADT: 160

BUTTE RD; N 1000 E

Good

Over: E.BR.SNAKE R.VALLEY CNL

1.6 N. 1.0 W. GOSHEN, Bingham, ID

Built 1974 Load: 28.1 t ADT: 100

BOND ROAD

Good

Over: DANSKIN CANAL

1.2 W. GROVELAND, Bingham, ID

Built 1968 Load: 28.1 t ADT: 1,100

N 115 E

Good

Over: WILLOW CREEK

1.8 S. 1.4 W. RIRIE, Bonneville, ID

Built 1962 Load: 28.1 t ADT: 50

JAMESTON ROAD

Good

Over: BUTTE ARM CANAL

3.8 S. 1.3 W. IDAHO FALLS, Bonneville, ID

Built 1958 Load: 28.1 t ADT: 1,200

STC 3747;LAKESHORE

Good

Over: NEW YORK CANAL

4.7S 0.9W NAMPA CITY CTR, Canyon, ID

Built 1986 Load: 28.1 t ADT: 3,600

SUGAR AVENUE

Good

Over: INDIAN CREEK

IN NAMPA, Canyon, ID

Built 2004 Load: 28.1 t ADT: 190

HARMONY HEIGHTS RD

Good

Over: OROFINO CREEK(NOAH'S BR)

0.1 N. 0.3 E. OROFINO, Clearwater, ID

Built 2000 Load: 28.1 t ADT: 610

DEPT OF LANDS ROAD

Good

Over: ELK CREEK

0.6 N. 0.2 W. ELK RIVER, Clearwater, ID

Built 1982 Load: 28.1 t ADT: 260

WESTLAKE ROAD

Good

Over: WILLOW CREEK

1.8 S. 6.0 W. FERDINAND, Idaho, ID

Built 1996 Load: 28.1 t ADT: 70

N 3000 E

Good

Over: TETON ISLAND CANAL

4.4 N. 3.6 E. REXBURG, Madison, ID

Built 1977 Load: 28.1 t ADT: 110

W 4500 N

Good

Over: ST ANTHONY CANAL

0.22 W PLANO, Madison, ID

Built 1990 Load: 28.1 t ADT: 10

STC3702;CLOVER-3CR

Good

Over: E. FORK BRUNEAU RIVER

25.8 W 5.0 S. CASTLEFORD, Owyhee, ID

Built 2000 Load: 28.1 t ADT: 100

STC5759;W MCKINLEY

Good

Over: GOVERNMENT CREEK

SMELTERVILLE ECL, Shoshone, ID

Built 2010 Load: 28.1 t ADT: 1,100

STC 6809;N 500 W

Good

Over: N.FK. LEIGH CREEK

0.6 N. 2.5 E. TETONIA, Teton, ID

Built 1977 Load: 28.1 t ADT: 680

SCOTT MTN ROAD

Good

Over: DEADWOOD RIVER

0.25 E DEADWOOD DAM, Valley, ID

Built 1982 Load: 28.1 t ADT: 30

LANDMARK/STANLEY

Good

Over: JOHNSON CREEK

23 N. DEADWOOD RESV, Valley, ID

Built 1999 Load: 28.1 t ADT: 30

12166: CLYDE RD.

Good

Over: Little Lost River

.1 mi E of L Lost Rvr HWY, Butte, ID

Built 2003 Load: 28.2 t ADT: 25

FDR

Good

Over: BIG CASINO CREEK

BIG CASINO CAMPGROUND, Custer, ID

Built 1969 Load: 28.2 t ADT: 80

SHAW LANE

Good

Over: MIDDLE LINE CANAL

2.0 N. 1.1 E. GRANDVIEW, Elmore, ID

Built 2022 Load: 28.2 t ADT: 30

TAMARACK FLAT ROAD

Good

Over: THIRD FORK

5.5 MI SW GRANITE PEAK, Gem, ID

Built 1970 Load: 28.2 t ADT: 15

FOREST RD. 221-2

Good

Over: SLATE CR

32 MI. FROM GRANGEVILLE, Idaho, ID

Built 1976 Load: 28.2 t ADT: 40

FS ROUTE NO. 338

Good

Over: BIRD CREEK

BIRD CREEK, Shoshone, ID

Built 2001 Load: 28.2 t ADT: 40

ROAD

Good

Over: NO FORK PACKSADDLE CREEK

NO DATA ENTERED, Teton, ID

Built 2009 Load: 28.2 t ADT: 50

4248: SHOSHONE CRE

Good

Over: Shoshone Creek

11.1 mi E of I93, Twin Falls, ID

Built 1985 Load: 28.2 t ADT: 25

TRAIL CREEK ROAD

Good

Over: TRAIL CREEK

2 MI SSW DEADWOOD RSRVOIR, Valley, ID

Built 1981 Load: 28.2 t ADT: 5

Showing 1,201-1,250 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.