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 #442

Fair

Over: TRAIL CREEK

AT MAGEE RANGER STATION, Shoshone, ID

Built 1984 Load: 25.9 t ADT: 50

THOMAS ROAD

Fair

Over: PEOPLES CANAL

1.0 W. THOMAS, Bingham, ID

Built 1971 Load: 26.1 t ADT: 900

SMITH CREEK ROAD

Fair

Over: M.FK.PAYETTE R;R.SMITH C

3.2 N. 0.2 E. CROUCH, Boise, ID

Built 1973 Load: 26.1 t ADT: 25

NEAL ROAD

Fair

Over: S.FK.BOISE RIVER

3.1 N. 7.4 W. PRAIRIE, Elmore, ID

Built 1961 Load: 26.1 t ADT: 100

N 5050 E

Fair

Over: SNAKE RIVER;HEISE BR

1.3 N. 4.0 E. RIRIE, Jefferson, ID

Built 1975 Load: 26.1 t ADT: 550

IOWA AVENUE

Fair

Over: LOWER PAYETTE CANAL

1.5 N. 1.1 E. PAYETTE, Payette, ID

Built 1940 Load: 26.1 t ADT: 150

FS ROUTE NO. 1082

Fair

Over: TRESTLE CREEK

TRESTLE CREEK, Bonner, ID

Built 1969 Load: 26.2 t ADT: 50

FDR

Fair

Over: PARADISE CREEK

4 MILES ABOVE METH.CAMP, Camas, ID

Built 1976 Load: 26.2 t ADT: 30

BEAVER-LOON ROAD

Fair

Over: BEAVER CREEK

NO DATA ENTERED, Custer, ID

Built 1967 Load: 26.2 t ADT: 10

BEAVER-LOON ROAD

Fair

Over: NELSON CREEK

19 MILES NORTH OF SUNBEAM, Custer, ID

Built 1967 Load: 26.2 t ADT: 10

BULL CREEK ROAD

Fair

Over: LITTLE LOST RIVER

NO DATA ENTERED, Custer, ID

Built 1971 Load: 26.2 t ADT: 10

E.FK.-FLY CK. ROAD

Fair

Over: EAST FORK SWANHOLM

12 MI WNW OF ATLANTA ID, Elmore, ID

Built 1976 Load: 26.2 t ADT: 5

RAMMAGE MEADOWS RD

Fair

Over: SEC.FK.CHIEF EAGLE EYE

2 MI N OF SAGEHEN RSRVOIR, Gem, ID

Built 1977 Load: 26.2 t ADT: 5

NO DATA ENTERED

Fair

Over: YELLOWJACKET CREEK

NO DATA ENTERED, Lemhi, ID

Built 1963 Load: 26.2 t ADT: 50

NO DATA ENTERED

Fair

Over: NORTH FORK SALMON

NO DATA ENTERED, Lemhi, ID

Built 1958 Load: 26.2 t ADT: 50

NO DATA ENTERED

Fair

Over: NORTH FORK SALMON

NO DATA ENTERED, Lemhi, ID

Built 1959 Load: 26.2 t ADT: 50

NHS 7433;VISTA AVE

Fair

Over: NEW YORK CANAL

IN BOISE;VISTA AVE., Ada, ID

Built 1973 Load: 26.3 t ADT: 27,000

SMA3778;DRY CRK RD

Fair

Over: DRY CREEK

HIDDEN SPRINGS, Ada, ID

Built 2006 Load: 26.3 t ADT: 1,600

US 95

Fair

Over: GOLDEN GATE CANAL

WILDER SCL, Canyon, ID

Built 1956 Load: 26.3 t ADT: 7,100

790N-1350E

Fair

Over: MAIN SOUTHSIDE CANAL

8.9 N. 5.0 E. DECLO, Cassia, ID

Built 1980 Load: 26.3 t ADT: 50

N 3200 E (HUNTER)

Fair

Over: DRY BED CR;W.LEWISVILLE

0.3 N. 2.6 W. LEWISVILLE, Jefferson, ID

Built 1964 Load: 26.3 t ADT: 40

I 84 EBL

Fair

Over: 'J' COULEE CANAL

0.5 W. JEROME, Jerome, ID

Built 1966 Load: 26.3 t ADT: 12,500

I 90RAMP WB ON

Fair

Over: BIKE/PED UNDERPASS

IN WALLACE, Shoshone, ID

Built 1991 Load: 26.3 t ADT: 800

STC5758;BEAVER CRK

Fair

Over: BEAVER CREEK

6.0 N. 1.0 E. WALLACE, Shoshone, ID

Built 1973 Load: 26.3 t ADT: 110

EAST FORK ROAD

Fair

Over: SECESH RIVER

7.9 N. 19.1 E. MCCALL, Valley, ID

Built 1941 Load: 26.3 t ADT: 40

FS ROUTE NO. 419

Fair

Over: MORRIS CREEK

MORRIS CREEK, Bonner, ID

Built 1952 Load: 26.6 t ADT: 50

FS ROUTE NO. 2517

Fair

Over: SPRUCE CREEK

SPRUCE CREEK, Boundary, ID

Built 1977 Load: 26.6 t ADT: 40

FDR

Fair

Over: PARADISE CREEK

BIG SMOKEY ADMIN. SITE, Camas, ID

Built 1962 Load: 26.6 t ADT: 50

FDR 711

Fair

Over: QUARTZ CREEK NO 2

48 MILES FROM PIERCE ID, Clearwater, ID

Built 1967 Load: 26.6 t ADT: 5

CUSTER MOTORWAY

Fair

Over: YANKEE FORK

NO DATA ENTERED, Custer, ID

Built 1969 Load: 26.6 t ADT: 100

BASIN CREEK ROAD

Fair

Over: EAST FORK BASIN CREEK

NO DATA ENTERED, Custer, ID

Built 1979 Load: 26.6 t ADT: 40

NO DATA ENTERED

Fair

Over: SWAMP CREEK

ELK SUMMIT ROAD 111, Idaho, ID

Built 1950 Load: 26.6 t ADT: 30

FOREST ROAD 309

Fair

Over: MILL CREEK

2.1 MI. FROM STATE HWY 14, Idaho, ID

Built 1966 Load: 26.6 t ADT: 30

FOREST ROAD 309

Fair

Over: MILL CREEK

2.8 MI. FROM STATE HWY 14, Idaho, ID

Built 1966 Load: 26.6 t ADT: 30

FS ROUTE NO. 534

Fair

Over: TRAIL CREEK

TRAIL CREEK, Kootenai, ID

Built 1953 Load: 26.6 t ADT: 50

BEAR VALLEY CR. RD

Fair

Over: BEAR VALLEY CREEK

BEAR VALLEY CREEK, Lemhi, ID

Built 1966 Load: 26.6 t ADT: 10

NO DATA ENTERED

Fair

Over: BEAVER CREEK

FLUME BRIDGE, Clearwater, ID

Built 1967 Load: 26.9 t ADT: 140

YUBA RIVER ROAD

Fair

Over: YUBA RIVER

2 MI SW ATLANTA ,IDAHO, Elmore, ID

Built 1976 Load: 26.9 t ADT: 15

FDR 373

Fair

Over: BRUSHY FORK

22 MI EAST OF POWELL R S, Idaho, ID

Built 1956 Load: 26.9 t ADT: 60

FDR 111

Fair

Over: WHITE SANDS CREEK

WHITE SANDS-RD 111, Idaho, ID

Built 1970 Load: 26.9 t ADT: 50

GOODRICH CREEK RD

Fair

Over: WEISER RIVER

5.4 S. 5.7 W. COUNCIL, Adams, ID

Built 1930 Load: 27.0 t ADT: 140

SHELTON CEMETRY RD

Fair

Over: ANDERSON CANAL

1.0 S. 1.1 W. RIRIE, Bonneville, ID

Built 1941 Load: 27.0 t ADT: 1,700

BISHOP ROAD

Fair

Over: NOBLE CANAL

0.2 N. 1.2 W. LETHA, Gem, ID

Built 1974 Load: 27.0 t ADT: 50

N 4600 E

Fair

Over: RUDY CANAL

2.0 N. 0.4 W. RIRIE, Jefferson, ID

Built 1973 Load: 27.0 t ADT: 20

SH 75

Fair

Over: BIG WOOD RIVER

14.6 N. KETCHUM, Blaine, ID

Built 1958 Load: 27.2 t ADT: 1,500

STC 3883;ROBIE CRK

Fair

Over: MORES CREEK

13.6 S. 8.1 W. IDAHO CITY, Boise, ID

Built 1997 Load: 27.2 t ADT: 300

STC 6749; 2900N

Fair

Over: BIG LOST RIVER

2.7 S. 0.2 E. MOORE, Butte, ID

Built 1926 Load: 27.2 t ADT: 160

SH 45

Fair

Over: MORA CANAL

7.5 S. NAMPA, Canyon, ID

Built 1956 Load: 27.2 t ADT: 3,400

I 84 EB OFF RAMP

Fair

Over: BOISE RIVER;RAMP AB BR

IN CALDWELL, Canyon, ID

Built 1980 Load: 27.2 t ADT: 5,000

E. 100 S.

Fair

Over: MARSH CREEK

0.2 S. 2.4 E. DECLO, Cassia, ID

Built 1999 Load: 27.2 t ADT: 100

Showing 551-600 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.