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

EVENT CENTER DRIVE

Good

Over: PORTER CANAL

IN IDAHO FALLS, Bonneville, ID

Built 2019 Load: 55.7 t ADT: 500

STP7243;E PARK CTR

Good

Over: LOGGERS CREEK

EAST BOISE, Ada, ID

Built 2009 Load: 56.4 t ADT: 9,600

SH 46

Good

Over: CEDAR DRAW CANAL

5.4 S. WENDELL, Gooding, ID

Built 2015 Load: 56.4 t ADT: 2,800

STEAMBOAT ROAD

Good

Over: STEAMBOAT CREEK

STEAMBOAT FORD SITE, Idaho, ID

Built 2007 Load: 56.4 t ADT: 5

FDR 250

Good

Over: OROGRANDE CREEK

29 MILES NTH OF PIERCE, Clearwater, ID

Built 1972 Load: 57.7 t ADT: 100

US 95

Good

Over: COCOLALLA CREEK

1.6 N. CAREYWOOD, Bonner, ID

Built 2017 Load: 58.0 t ADT: 11,000

S. BAILEY WAY

Good

Over: TEN MILE CREEK

2.0 S. 0.7 E. MERIDIAN, Ada, ID

Built 2007 Load: 58.1 t ADT: 200

I 86B

Good

Over: UPRR;AMERICAN FALLS OP

0.2 W. AMERICAN FALLS, Power, ID

Built 1990 Load: 58.1 t ADT: 3,300

BARBER VALLEY DR

Good

Over: WALLING CREEK

SE BOISE, Ada, ID

Built 2018 Load: 58.6 t ADT: 5,500

RATTLESNAKE CRK R

Good

Over: SALMON RIVER

18.8 S. SALMON, Lemhi, ID

Built 2016 Load: 58.6 t ADT: 60

STADIUM DR

Good

Over: PARADISE CREEK

IN MOSCOW @ U OF I, Latah, ID

Built 2010 Load: 59.0 t ADT: 7,000

BROOKSIDE LANE

Good

Over: DRY CREEK

2.0 N. 1.8 E. EAGLE, Ada, ID

Built 1994 Load: 59.9 t ADT: 250

FOREST ROAD 30413

Good

Over: FISH HAVEN CREEK

NO DATA ENTERED, Bear Lake, ID

Built 2006 Load: 60.3 t ADT: 50

FDR 250

Good

Over: N FK CLEARWATER RIV

VIC OF JCT FDR 250/255, Clearwater, ID

Built 1970 Load: 60.6 t ADT: 100

ANDERSON DAM RD

Good

Over: CASTLE CREEK

5.0 S 4.3 W PINE, Elmore, ID

Built 2014 Load: 60.9 t ADT: 30

FS ROUTE NO. 218

Good

Over: GOLD CREEK

JCT. ROAD 218 & FH 50, Shoshone, ID

Built 1980 Load: 60.9 t ADT: 40

GROUSE CR-MARSHAL

Good

Over: GROUSE CREEK

ON THE GROUSE CREEK ROAD, Idaho, ID

Built 2004 Load: 62.2 t ADT: 50

2400 NORTH ROAD

Good

Over: BIG LOST RIVER

0.9 S. 0.7 W. ARCO, Butte, ID

Built 2012 Load: 63.5 t ADT: 200

S 1050 E RD

Good

Over: J CANAL

2.0 E 0.75 S DECLO, Cassia, ID

Built 2000 Load: 63.5 t ADT: 30

FISH HATCHERY ROAD

Good

Over: RILEY CREEK

ENTRANCE ROAD, Gooding, ID

Built 2015 Load: 63.5 t ADT: 200

N. GRAND LAKE WAY

Good

Over: FIVE MILE CREEK

3.45 N. MERIDIAN, Ada, ID

Built 2022 Load: 64.2 t ADT: 50

OLD HWY 46;500 E

Good

Over: CAMAS CREEK

3.1 S. 5.0 E. FAIRFIELD, Camas, ID

Built 2016 Load: 64.4 t ADT: 20

REYNOLDS CR RD

Good

Over: REYNOLDS CREEK

0.5 S 10.2 W MURPHY, Owyhee, ID

Built 2012 Load: 65.1 t ADT: 200

HAYLAND ROAD

Good

Over: MIDDLE LINE CANAL

2.1 N 1.0 E GRANDVIEW, Elmore, ID

Built 2004 Load: 65.3 t ADT: 200

LEESBURG ROAD

Good

Over: ARNETT CREEK

NO DATA ENTERED, Lemhi, ID

Built 1994 Load: 67.1 t ADT: 50

US 95

Good

Over: LAPWAI CREEK

2.6 N. 1.2 E. WINCHESTER, Lewis, ID

Built 2020 Load: 70.3 t ADT: 3,500

SH 6

Good

Over: E.FK.MEADOW CREEK

6.3 N. HARVARD, Latah, ID

Built 1991 Load: 70.8 t ADT: 710

SWALE ROAD

Good

Over: RENWYCK CREEK

3 MI N OF SAGEHEN RSRVOIR, Gem, ID

Built 2006 Load: 72.3 t ADT: 50

US 93

Good

Over: N. FORK SALMON RIVER

15.1 N. NORTH FORK, Lemhi, ID

Built 1997 Load: 73.5 t ADT: 730

STC 7073;S.COLE RD

Good

Over: NEW YORK CANAL

ON S.COLE RD;0.3N.VALLEJO, Ada, ID

Built 1989 Load: 76.2 t ADT: 2,200

1000 EAST ROAD

Good

Over: N.FK. LEIGH CREEK

0.2 N. 3.5 E. TETONIA, Teton, ID

Built 2004 Load: 76.2 t ADT: 150

N. ECHOHAWK WAY

Good

Over: FARMERS UNION CANAL

IN EAGLE, Ada, ID

Built 1999 Load: 78.0 t ADT: 200

E 500 N

Good

Over: ENTERPRISE CANAL

2.9 S 0.2 W CHESTER, Fremont, ID

Built 2011 Load: 78.0 t ADT: 70

US 89

Good

Over: MONTPELIER CREEK

7.0 E. MONTPELIER, Bear Lake, ID

Built 2003 Load: 81.6 t ADT: 1,300

SH 43

Good

Over: WILLOW CREEK

2.0 S. UCON, Bonneville, ID

Built 1994 Load: 83.5 t ADT: 6,100

SMA 7674;MTN VIEW

Good

Over: PARADISE CREEK

MTN VIEW @ WHITE AVE., Latah, ID

Built 1997 Load: 87.1 t ADT: 5,700

N FAWNRIDGE WAY

Good

Over: FIVE MILE CREEK

2.3 N 3.5 W. MERIDIAN, Ada, ID

Built 2022 Load: 97.2 t ADT: 100

E. BRANCHWOOD

Good

Over: SQUAW CREEK

IN BOISE, Ada, ID

Built 2001 Load: 99.9 t ADT: 400

US 89

Good

Over: MONTPELIER CK;LOWER NRWS

4.1 E. MONTPELIER, Bear Lake, ID

Built 2008 Load: 99.9 t ADT: 1,300

STC4782;GRANGEMONT

Good

Over: WHISKEY CREEK

4.2 N. 8.9 E. OROFINO, Clearwater, ID

Built 1962 Load: 99.9 t ADT: 540

KING HILL RD

Good

Over: LITTLE CANYON CREEK

6.5N. 0.8E. GLENNS FERRY, Elmore, ID

Built 1999 Load: 99.9 t ADT: 20

US 91

Good

Over: WEST CACHE CANAL

3.2 N. PRESTON, Franklin, ID

Built 1993 Load: 99.9 t ADT: 2,300

SMA 7754;D ST

Good

Over: PARADISE CREEK

IN MOSCOW, Latah, ID

Built 1950 Load: 99.9 t ADT: 1,500

US 93

Good

Over: N. FORK SALMON RIVER

15.1 N. NORTH FORK, Lemhi, ID

Built 1997 Load: 99.9 t ADT: 730

US 93

Good

Over: N. FORK SALMON RIVER

16.0 N. NORTH FORK, Lemhi, ID

Built 1997 Load: 99.9 t ADT: 730

BED ROCK FLAT ROAD

Good

Over: HOG CREEK

0.5S 9.3E MIDVALE, Washington, ID

Built 2002 Load: 99.9 t ADT: 50

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

Showing 1,601-1,650 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.