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

CDA RIVER ROAD

Fair

Over: LOST CREEK

4.9 N. PRICHARD, Shoshone, ID

Built 1953 Load: 20.9 t ADT: 30

3100 EAST ROAD

Fair

Over: LOW LINE CANAL

4.2 S. 1.5 E. TWIN FALLS, Twin Falls, ID

Built 1965 Load: 20.9 t ADT: 140

1500 EAST ROAD

Fair

Over: LOW LINE CANAL

2.5 S. 0.5 E. BUHL, Twin Falls, ID

Built 1936 Load: 20.9 t ADT: 80

2100 EAST RD

Fair

Over: LOW LINE CANAL

1.1S 1.0W FILER;JRDN COR, Twin Falls, ID

Built 1968 Load: 20.9 t ADT: 150

1500 EAST ROAD

Fair

Over: HIGH LINE CANAL

7.2 S. 0.5 E. BUHL, Twin Falls, ID

Built 1930 Load: 20.9 t ADT: 20

2800 EAST RD

Fair

Over: HIGH LINE CANAL

4.8 S. 1.5 W. TWIN FALLS, Twin Falls, ID

Built 1972 Load: 20.9 t ADT: 90

2500 EAST ROAD

Fair

Over: LOW LINE CANAL

2.5 S. 2.7 E. FILER, Twin Falls, ID

Built 1930 Load: 20.9 t ADT: 140

N 1700 E

Fair

Over: LATERAL 17A

2.4 E. 3.3 S. BUHL, Twin Falls, ID

Built 1969 Load: 20.9 t ADT: 400

3200 EAST RD

Fair

Over: HIGH LINE CANAL

6.4 S. 2.5 E. TWIN FALLS, Twin Falls, ID

Built 1969 Load: 20.9 t ADT: 140

2500 EAST ROAD

Fair

Over: HIGH LINE CANAL

4.3 S. 2.7 E. FILER, Twin Falls, ID

Built 1964 Load: 20.9 t ADT: 140

RIVER ROAD

Fair

Over: MUD CREEK

4.2 N. 5.6 W. BUHL, Twin Falls, ID

Built 1983 Load: 20.9 t ADT: 60

LICK CREEK ROAD

Fair

Over: SECESH RIVER

20.2 E. MCCALL, Valley, ID

Built 1952 Load: 20.9 t ADT: 40

GOLD DUST ROAD

Fair

Over: BIG CREEK

2.3 S. 3.0 E. CASCADE, Valley, ID

Built 1975 Load: 20.9 t ADT: 70

DEADWOOD ROAD

Fair

Over: DEADWOOD RIVER

3 N. DEADWOOD RESV, Valley, ID

Built 1959 Load: 20.9 t ADT: 30

STC8217;COVE ROAD

Fair

Over: WEISER R;BACKWATER CH.BR

AT WEISER ECL;MAIN ST., Washington, ID

Built 1960 Load: 20.9 t ADT: 480

ROAD

Fair

Over: WILLOW CREEK

NO DATA ENTERED, Fremont, ID

Built 1975 Load: 21.1 t ADT: 50

FDR 103

Fair

Over: LOLO CREEK

1 MI WEST OF MUSSELSHELL, Idaho, ID

Built 1962 Load: 21.1 t ADT: 40

FOREST ROAD 648

Fair

Over: MEADOW CREEK

CAMP 58, Idaho, ID

Built 1991 Load: 21.1 t ADT: 50

FS ROUTE NO. 804

Fair

Over: MINERS CREEK

MINERS CREEK, Shoshone, ID

Built 1986 Load: 21.1 t ADT: 50

FDR

Fair

Over: NORTH FORK WOOD RIVER

1 MILE NORTH SNRA HQDS., Blaine, ID

Built 1956 Load: 21.4 t ADT: 50

SQ___ CREEK ROAD

Fair

Over: PAASASIKWANA NAOKWAIDE

NO DATA ENTERED, Custer, ID

Built 1964 Load: 21.4 t ADT: 20

FOREST ROAD 290

Fair

Over: MEADOW CREEK

INDIAN HILL, Idaho, ID

Built 1934 Load: 21.4 t ADT: 50

RIVER ROAD

Fair

Over: GREAT WESTERN CANAL

7.1 N. 1.1 W. IDAHO FALLS, Bonneville, ID

Built 1960 Load: 21.6 t ADT: 1,300

W 2000 S

Fair

Over: TEXAS SLOUGH CANAL

0.6 E. BURTON, Madison, ID

Built 1955 Load: 21.6 t ADT: 330

2100 EAST RD

Fair

Over: HIGH LINE CANAL

3.1S 1.0W FILER;JRDN COR, Twin Falls, ID

Built 1962 Load: 21.6 t ADT: 100

BEAVER-LOON ROAD

Fair

Over: LOON CREEK

NO DATA ENTERED, Custer, ID

Built 1957 Load: 21.7 t ADT: 10

ROAD

Fair

Over: TRAIL CREEK

NO DATA ENTERED, Teton, ID

Built 1965 Load: 21.7 t ADT: 50

FUNK ROAD

Fair

Over: LOW LINE CANAL

2.5S. 0.9E.ABERDEEN;2000S, Bingham, ID

Built 1958 Load: 21.8 t ADT: 200

STC 6712;S 25TH E

Fair

Over: TAYLOR CANAL

4.48 S. AMMON, Bonneville, ID

Built 1949 Load: 21.8 t ADT: 1,600

STC 5803;MOYIE RVR

Fair

Over: MOYIE RIVER;MEADOW CREEK

10.2 S. ADDIE, Boundary, ID

Built 1928 Load: 21.8 t ADT: 120

STEPHEN LANE

Fair

Over: RIVERSIDE CANAL

3.2 S. 0.7 W. PARMA, Canyon, ID

Built 1983 Load: 21.8 t ADT: 200

MOSCRIP ROAD

Fair

Over: OROFINO CREEK

IN PIERCE, Clearwater, ID

Built 1978 Load: 21.8 t ADT: 190

N 4950 E

Fair

Over: EAGLE ROCK CANAL

0.2 N. 3.1 E. RIRIE, Jefferson, ID

Built 1950 Load: 21.8 t ADT: 550

JENKINS ROAD

Fair

Over: COW CREEK

2.5 N. 1.6 E. GENESEE, Latah, ID

Built 1935 Load: 21.8 t ADT: 30

FS ROUTE NO. 447

Fair

Over: E.F. EMERALD

E.F. EMERALD CREEK, Benewah, ID

Built 1967 Load: 22.0 t ADT: 40

FDR

Fair

Over: WARM SPRINGS CREEK

16 MILES WEST OF KETCHUM, Blaine, ID

Built 1959 Load: 22.0 t ADT: 50

WILLIS FLAT ROAD

Fair

Over: SO.FK.PAYETTE RIVER

14 MI EAST OF LOWMAN, ID, Boise, ID

Built 1959 Load: 22.0 t ADT: 35

SQ___ CREEK ROAD

Fair

Over: JACKKNIFE CREEK

NO DATA ENTERED, Bonneville, ID

Built 1963 Load: 22.0 t ADT: 20

SMITH CREEK ROAD

Fair

Over: SMITH CREEK

2.8 MI. NE OF PRAIRIE, Elmore, ID

Built 1972 Load: 22.0 t ADT: 25

ROAD

Fair

Over: BIG SPRINGS OUTLET

NO DATA ENTERED, Fremont, ID

Built 1957 Load: 22.0 t ADT: 50

FDR 1433

Fair

Over: N FK PALOUSE

23 MILES FROM POTLATCH RS, Latah, ID

Built 1963 Load: 22.0 t ADT: 10

FS ROUTE NO. 321

Fair

Over: MARBLE CREEK

MARBLE CREEK, Shoshone, ID

Built 1959 Load: 22.0 t ADT: 50

FS ROUTE NO. 447

Fair

Over: EMERALD CREEK

EMERALD CREEK, Benewah, ID

Built 1967 Load: 22.4 t ADT: 50

FDR

Fair

Over: BIG SMOKY CREEK

2 MILES WEST BIG SMOKY JT, Camas, ID

Built 1953 Load: 22.4 t ADT: 50

SMITH CREEK ROAD

Fair

Over: SMITH CREEK

5.7 MI. NE OF PRAIRIE, Elmore, ID

Built 1972 Load: 22.4 t ADT: 25

BARBER FLAT ROAD

Fair

Over: NORTH FORK BOISE RIVER

25 MI EAST OF ID CITY, Elmore, ID

Built 1959 Load: 22.4 t ADT: 15

FOREST ROAD 1858

Fair

Over: NEWSOME CREEK

NEWSOME DRAINAGE, Idaho, ID

Built 1962 Load: 22.4 t ADT: 50

FOREST ROAD 1858

Fair

Over: NEWSOME CREEK

NEWSOME DRAINAGE, Idaho, ID

Built 1961 Load: 22.4 t ADT: 50

NO DATA ENTERED

Fair

Over: HAZARD CREEK

NO DATA ENTERED, Idaho, ID

Built 1951 Load: 22.4 t ADT: 50

FS ROUTE NO. 411

Fair

Over: BURNT CABIN CR

BURNT CABIN CREEK, Kootenai, ID

Built 1948 Load: 22.4 t ADT: 50

Showing 401-450 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.