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

IRR BIA RTE 32

Fair

Over: LITTLE HANGMAN CREEK

8 KM SW OF AGENCY, Benewah, ID

Built 1972 Load: 24.5 t ADT: 700

IRR BIA RTE 10

Fair

Over: LITTLE HANGMAN CREEK

6.4 KM SW OF AGENCY, Benewah, ID

Built 1977 Load: 24.5 t ADT: 50

IRR BIA RTE 24

Fair

Over: LITTLE HANGMAN CREEK

4 KM SOUTHWEST OF AGENCY, Benewah, ID

Built 1977 Load: 24.5 t ADT: 20

IRR BIA RTE 68

Fair

Over: SPRING CREEK

10 KM WEST OF FORT HALL, Bingham, ID

Built 1974 Load: 24.5 t ADT: 60

IRR BIA RTE 64

Fair

Over: SPRING CREEK

8 KM NW OF FORT HALL, Bingham, ID

Built 1983 Load: 24.5 t ADT: 35

IRR BIA RTE 10

Fair

Over: NORTH CANAL

2 KM SE OF JCT US 191& 26, Bingham, ID

Built 1991 Load: 24.5 t ADT: 30

S. LAVASIDE ROAD

Fair

Over: PEOPLES CANAL

0.5 N. 1.8 W. KIMBALL, Bingham, ID

Built 1986 Load: 24.5 t ADT: 95

STP8393;FRANKLIN B

Fair

Over: PHYLLIS CANAL

IN NAMPA;FRANKLIN BLVD., Canyon, ID

Built 1963 Load: 24.5 t ADT: 23,000

REID SPRING ROAD

Fair

Over: RAFT RIVER

3.5 S. 1.0 E. ALMO, Cassia, ID

Built 2001 Load: 24.5 t ADT: 200

LOWER FORD CRK RD

Fair

Over: JIM FORD CREEK

2.8 S. 2.3 E. OROFINO, Clearwater, ID

Built 1977 Load: 24.5 t ADT: 480

HATTER CREEK ROAD

Fair

Over: HATTER CREEK

4.1 S. 0.5 E. PRINCETON, Latah, ID

Built 1970 Load: 24.5 t ADT: 30

ENTRANCE ROAD

Fair

Over: LAPWAI CREEK

1.4 miles southeast of Jc, Nez Perce, ID

Built 1988 Load: 24.5 t ADT: 225

FDR

Fair

Over: NORTH FORK OF WOOD RIVER

4 MILES NORTH SNRA HQDS, Blaine, ID

Built 1955 Load: 24.6 t ADT: 50

FIVE MILE ROAD

Fair

Over: FIVE MILE CREEK

1 MI N.E. OF HELENDE C.G., Boise, ID

Built 1981 Load: 24.6 t ADT: 10

NO DATA ENTERED

Fair

Over: MOOSE CREEK

NO DATA ENTERED, Lemhi, ID

Built 1979 Load: 24.6 t ADT: 50

FDR

Fair

Over: SMILEY CREEK

SAWTOOTH VALLEY SMILEY CR, Blaine, ID

Built 1979 Load: 24.9 t ADT: 25

KANE CREEK ROAD

Fair

Over: KANE CREEK

NO DATA ENTERED, Custer, ID

Built 1966 Load: 24.9 t ADT: 40

WAGONTOWN ROAD

Fair

Over: TRINITY CREEK

1 MI SW FEAHTERVILLE ID, Elmore, ID

Built 1966 Load: 24.9 t ADT: 25

ROAD

Fair

Over: HENRYS LAKE OUTLET

NO DATA ENTERED, Fremont, ID

Built 1991 Load: 24.9 t ADT: 50

FDR 60099

Fair

Over: COPPER CREEK

COBALT WORK CENTER, Lemhi, ID

Built 1971 Load: 24.9 t ADT: 5

NO DATA ENTERED

Fair

Over: INDIAN CREEK

NO DATA ENTERED, Lemhi, ID

Built 1963 Load: 24.9 t ADT: 200

S3784;LOCUST GROVE

Fair

Over: RAWSON CANAL

5.3 S. 0.8 E. MERIDIAN, Ada, ID

Built 1973 Load: 25.2 t ADT: 1,500

N 1200 E RD

Fair

Over: OWSLEY CNL;SW.TERRETON

0.9 S. 1.0 W. TERRETON, Jefferson, ID

Built 1974 Load: 25.2 t ADT: 40

EXPERIMENT STATION

Fair

Over: LITTLE HOLE DRAW CREEK

IN ABERDEEN N/E CL, Bingham, ID

Built 2017 Load: 25.3 t ADT: 400

FALL CK.-ROCKY BAR

Fair

Over: FALL CREEK

2 MI S. OF RED MOUNTAIN, Elmore, ID

Built 1984 Load: 25.3 t ADT: 20

YELLOWJACKET ROAD

Fair

Over: YELLOWJACKET CREEK

NO DATA ENTERED, Lemhi, ID

Built 1956 Load: 25.3 t ADT: 50

HOMESTEAD ROAD

Fair

Over: LOW LINE CANAL

3.5S. 0.2E.ABERDEEN;2100S, Bingham, ID

Built 1958 Load: 25.4 t ADT: 200

STC 6749;2500N

Fair

Over: BIG LOST RIVER

1.4 W. 0.1 N. ARCO, Butte, ID

Built 1926 Load: 25.4 t ADT: 490

STP8393;FRANKLIN B

Fair

Over: PHYLLIS CANAL

IN NAMPA;FRANKLIN BLVD., Canyon, ID

Built 1963 Load: 25.4 t ADT: 26,500

100 SOUTH ROAD

Fair

Over: 'H' CANAL;E.DECLO BR

0.2S 1.1E DECLO;955E-100S, Cassia, ID

Built 1985 Load: 25.4 t ADT: 100

S 100 W

Fair

Over: H CANAL

2.5 S 1.0 W BURLEY, Cassia, ID

Built 1983 Load: 25.4 t ADT: 410

CO. RD.;OLD US 93

Fair

Over: 'R' CANAL

13.2 N. TWIN FALLS, Jerome, ID

Built 1934 Load: 25.4 t ADT: 5

SMA 7872; 8TH ST

Fair

Over: 'B-4' CANAL

IN RUPERT;8TH STREET, Minidoka, ID

Built 1965 Load: 25.4 t ADT: 4,000

US 95

Fair

Over: RUSH CREEK

0.1 N. CAMBRIDGE NECL, Washington, ID

Built 1956 Load: 25.4 t ADT: 3,100

JONES ROAD

Fair

Over: MANN CREEK

5.5 N. 5.1 E. WEISER, Washington, ID

Built 1960 Load: 25.4 t ADT: 20

FS ROUTE NO. 419

Fair

Over: LIGHTNING CREEK

LIGHTNING CREEK, Bonner, ID

Built 1956 Load: 25.6 t ADT: 40

ROAD

Fair

Over: KNAPP CREEK

NO DATA ENTERED, Custer, ID

Built 1964 Load: 25.6 t ADT: 10

FOREST ROAD 1614

Fair

Over: CAREY CREEK

23.2 MI. FROM RIGGINS, ID, Idaho, ID

Built 1991 Load: 25.6 t ADT: 50

FOREST ROAD 309

Fair

Over: MILL CREEK

2.7 MI. FROM STATE HWY 14, Idaho, ID

Built 1966 Load: 25.6 t ADT: 30

FOREST ROAD 309

Fair

Over: SO. FK. CLEARWATER RIVER

19 MI. FROM GRANGEVILLE,, Idaho, ID

Built 1962 Load: 25.6 t ADT: 40

Taylor Boulevard

Fair

Over: Taylor Drainage

27.5 N. 15.6 W. Blackfoot, Bingham, ID

Built 1958 Load: 25.9 t ADT: 1,408

ROAD

Fair

Over: BEAR CREEK

NO DATA ENTERED, Bonneville, ID

Built 1986 Load: 25.9 t ADT: 36

FDR 711

Fair

Over: QUARTZ CREEK

49 MILES FROM PIERCE ID, Clearwater, ID

Built 1967 Load: 25.9 t ADT: 20

CUSTER MOTORWAY

Fair

Over: YANKEE FORK

NO DATA ENTERED, Custer, ID

Built 1973 Load: 25.9 t ADT: 100

THOMPSON CR ROAD

Fair

Over: THOMPSON CREEK

NO DATA ENTERED, Custer, ID

Built 1982 Load: 25.9 t ADT: 40

BEAVER-LOON ROAD

Fair

Over: BEAVER CREEK

NO DATA ENTERED, Custer, ID

Built 1972 Load: 25.9 t ADT: 5

FDR

Fair

Over: GERMANIA CEEEK

25 UP EAST FORK SALMON R., Custer, ID

Built 1956 Load: 25.9 t ADT: 50

FOREST ROAD 222C

Fair

Over: FOURTH OF JULY CREEK

NO DATA ENTERED, Idaho, ID

Built 2004 Load: 25.9 t ADT: 50

FS ROUTE NO. 209

Fair

Over: N.F.CDA RIVER

AT LEWELLING CREEK, Kootenai, ID

Built 1953 Load: 25.9 t ADT: 50

NO DATA ENTERED

Fair

Over: NORTH FORK SALMON

NO DATA ENTERED, Lemhi, ID

Built 1963 Load: 25.9 t ADT: 5

Showing 501-550 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.