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. 400

Good

Over: SVEE CREEK

19.4 MI FROM BABINS JCT., Shoshone, ID

Built 1976 Load: 46.0 t ADT: 40

US 30

Good

Over: PORTNEUF RIVER

1.9 W. LAVA HOT SPRINGS, Bannock, ID

Built 2008 Load: 46.3 t ADT: 5,800

US 89

Good

Over: OVID CREEK

3.77 N. PARIS, Bear Lake, ID

Built 2019 Load: 46.3 t ADT: 2,000

STC3753;LONE STAR

Good

Over: CALDWELL CANAL

6.0 S 1.4 E CALDWELL, Canyon, ID

Built 2010 Load: 46.3 t ADT: 710

US 95

Good

Over: MISSION CREEK

3.2 N. CULDESAC, Nez Perce, ID

Built 1997 Load: 46.3 t ADT: 3,500

OLD RIVER ROAD

Good

Over: LITTLE N.FK.CDA RIVER

3.4 N. 0.4 E. ENAVILLE, Shoshone, ID

Built 1985 Load: 46.8 t ADT: 100

STC 3938;ROSEBERRY

Good

Over: MUD CREEK

1.6 W. DONNELLY, Valley, ID

Built 2004 Load: 47.2 t ADT: 930

NO DATA ENTERED

Good

Over: GABE CREEK

NO DATA ENTERED, Idaho, ID

Built 2004 Load: 47.6 t ADT: 40

FDR 595

Good

Over: BOULDER CREEK

31 MILES FROM POWELL R S, Clearwater, ID

Built 1974 Load: 48.0 t ADT: 30

FS ROUTE NO. 208

Good

Over: DOWNEY CREEK

13.4 MI FROM BABINS JCT., Shoshone, ID

Built 1974 Load: 48.0 t ADT: 40

RIVER ROAD

Good

Over: DEEP CREEK

4.0 N. 2.5 W BUHL, Twin Falls, ID

Built 2018 Load: 48.0 t ADT: 130

FIRTH WAPELLO ROAD

Good

Over: SAND CREEK

1.4 S 1.3 E FIRTH, Bingham, ID

Built 2010 Load: 48.1 t ADT: 160

FLINT CREEK ROAD

Good

Over: JORDAN CREEK

38.4 W OREANA, Owyhee, ID

Built 2012 Load: 48.1 t ADT: 30

NO DATA ENTERED

Good

Over: NO DATA ENTERED

NO DATA ENTERED, Camas, ID

Built 2001 Load: 48.3 t ADT: 50

STC4790;THORN CRK

Good

Over: THORN CREEK

3.4 N. 3.7 W. GENESSE, Latah, ID

Built 2013 Load: 48.3 t ADT: 320

LEMHI ROAD

Good

Over: CANYON CREEK

0.8 N. 0.2 E. LEADORE, Lemhi, ID

Built 2012 Load: 48.3 t ADT: 100

FS ROUTE NO. 208

Good

Over: YELLOW DOG CR

14 MI FROM BABINS JCT., Shoshone, ID

Built 1974 Load: 48.3 t ADT: 40

DAGGER FALLS ROAD

Good

Over: BEAR VALLEY CREEK

1 MI N. OF BRUCE MEADOWS, Valley, ID

Built 1981 Load: 48.3 t ADT: 50

E. HYRUM DRIVE

Good

Over: SAND CREEK

4.5 N 0.2 E AMMON, Bonneville, ID

Built 2013 Load: 48.9 t ADT: 200

SH 25

Good

Over: 'A' CANAL

1.3 E. RUPERT, Minidoka, ID

Built 2000 Load: 49.0 t ADT: 3,600

I 15

Good

Over: RIVERSIDE CANAL

4.8 N. BLACKFOOT, Bingham, ID

Built 2019 Load: 49.6 t ADT: 25,500

EAST MAIN STREET

Good

Over: EAST CANAL

IN OAKLEY, Cassia, ID

Built 2020 Load: 49.6 t ADT: 350

DIAMOND CREEK ROAD

Good

Over: WALLACE CREEK

1.5 N 0.6 W CARMEN, Lemhi, ID

Built 2011 Load: 49.9 t ADT: 70

US 95

Good

Over: LAPWAI CREEK

2.9 N. 1.3 E. WINCHESTER, Lewis, ID

Built 2020 Load: 49.9 t ADT: 3,500

GLASSFORD WAY

Good

Over: FIVE MILE CREEK

NW MERIDIAN CL, Ada, ID

Built 2020 Load: 50.2 t ADT: 25

S 5500 W

Good

Over: TEXAS SLOUGH

2.6 N 2.0 W THORNTON, Madison, ID

Built 2012 Load: 50.2 t ADT: 150

STC7296;LINCOLN RD

Good

Over: SAND CREEK

0.3 W. LINCOLN, Bonneville, ID

Built 2016 Load: 50.5 t ADT: 7,900

TRINITY MTN RD

Good

Over: FALL CREEK

1.1 N 5.3 W PINE, Elmore, ID

Built 2014 Load: 50.5 t ADT: 120

FDR 447

Good

Over: NF PALOUSE RIVER

17 MILES FROM POTLATCH ID, Latah, ID

Built 1998 Load: 50.5 t ADT: 20

FDR 100

Good

Over: MUSSELSHELL CREEK

KAMIAH FORKS, Clearwater, ID

Built 1976 Load: 51.5 t ADT: 150

FDR 369

Good

Over: BRUSHY FORK CREEK

9 MI EAST OF POWELL RS, Idaho, ID

Built 1993 Load: 51.5 t ADT: 60

OLD HWY 28;BACK RD

Good

Over: KENNY CREEK

4.6 N. 0.5 W. TENDOY, Lemhi, ID

Built 2012 Load: 51.8 t ADT: 50

EASTSIDE DRIVE

Good

Over: LEMAH CREEK

4.8 N. 2.0 E. MCCALL, Valley, ID

Built 2015 Load: 51.8 t ADT: 100

NO DATA ENTERED

Good

Over: E. FK. BURNT LOG CREEK

NO DATA ENTERED, Valley, ID

Built 2022 Load: 51.8 t ADT: 50

NO DATA ENTERED

Good

Over: NO DATA ENTERED

NO DATA ENTERED, Bonneville, ID

Built 2009 Load: 52.5 t ADT: 50

ECHANOVE RD

Good

Over: CURRANT CREEK

IN BOISE;HIDDEN SPRINGS, Ada, ID

Built 2002 Load: 52.6 t ADT: 99

BAUMGARTNER RD

Good

Over: FEATHER RIVER

0.2 N FEATHERVILLE, Elmore, ID

Built 2010 Load: 52.6 t ADT: 10

US 95

Good

Over: LITTLE SALMON RIVER

0.2 W. NEW MEADOWS WCL, Adams, ID

Built 2021 Load: 52.8 t ADT: 3,700

FRUITVALE ROAD

Good

Over: WEISER RIVER

2.9 S. 2.7 W. EVERGREEN, Adams, ID

Built 2000 Load: 53.5 t ADT: 80

STC 3811; FH61 RD

Good

Over: S FK BOISE RVR (PINE BR)

0.3 S PINE, Elmore, ID

Built 2018 Load: 53.5 t ADT: 580

MYERS STREET

Good

Over: LOGGERS CREEK

IN BOISE;MYERS ST., Ada, ID

Built 1972 Load: 54.4 t ADT: 200

US 91

Good

Over: CEDAR POINT CANAL

2.5 NE FIRTH, Bingham, ID

Built 2004 Load: 54.8 t ADT: 3,600

FDR 255

Good

Over: NF CLEARWATER RIVER

KELLY FORKS BRIDGE, Clearwater, ID

Built 1968 Load: 54.8 t ADT: 80

RAMMAGE MEADOWS RD

Good

Over: SEC.FK.CHIEF EAGLE EYE

4 MI W SAGEN RESERVOIR, Gem, ID

Built 1990 Load: 54.8 t ADT: 20

SMA7217;S. VALLEY

Good

Over: AMI TRAIL

0.3 W. of I15 IC, Bannock, ID

Built 2016 Load: 55.1 t ADT: 5,200

OLYMPUS DR

Good

Over: FUTURE PED UNDERPASS

POCATELLO, Bannock, ID

Built 2018 Load: 55.1 t ADT: 6,500

SMA9773;LINDER RD

Good

Over: RIDENBAUGH CANAL

2.2 S. 1.1 W. MERIDIAN, Ada, ID

Built 1992 Load: 55.3 t ADT: 4,600

PRIEST ROAD

Good

Over: SILVER CREEK;S.E. PICABO

2.3 S. 2.7 E. PICABO, Blaine, ID

Built 1995 Load: 55.3 t ADT: 30

FIR GROVE ROAD

Good

Over: CAMAS CREEK

3.6 S. 2.3 E. FAIRFIELD, Camas, ID

Built 1986 Load: 55.3 t ADT: 30

STC8533;SMITH AVE

Good

Over: PHYLLIS CANAL

0.3 N 3.2 W NAMPA, Canyon, ID

Built 2010 Load: 55.3 t ADT: 590

Showing 1,551-1,600 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.