State profile · Below median Poor share

Idaho bridge safety

Condition ratings, load ratings, and Poor-condition data for every public highway bridge in Idaho, based on the FHWA National Bridge Inventory.

1,742
Public bridges
33.3%
Good condition
5.5%
Poor condition

Data updated May 2026

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 whose lowest applicable component is rated 0-4

-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 - Poor-condition share 18.4%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Idaho vs nearby ranks

Adjacent states by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below Idaho on the same metric.

KS

Kansas

5.25% top marginal rate
Structure
Progressive
Burden @ $100K
$23,867

WY

Wyoming

5.41% top marginal rate
Structure
Progressive
Burden @ $100K
$3,181
Selected

ID

Idaho

5.51% top marginal rate
Structure
Progressive
Burden @ $100K
$1,742

MS

Mississippi

5.92% top marginal rate
Structure
Progressive
Burden @ $100K
$16,823

SC

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 the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

All Bridges in Idaho

I 90 EBL & WBL

Unknown

Over: CROSSROAD BD;W.WALLACE I

IN WALLACE, Shoshone, ID

Built 1987 ADT: 1,100

I 90 EBL & WBL

Unknown

Over: COPPER STREET GS

IN MULLAN;COPPER STREET, Shoshone, ID

Built 1973 ADT: 30

OLD RIVER ROAD

Unknown

Over: ST JOE RIVER;AVERY BR

IN AVERY, Shoshone, ID

Built 1935 ADT: 360

SEVENTH STREET

Unknown

Over: RESIDENCE STREET;VIADUCT

IN WALLACE, Shoshone, ID

Built 1984 ADT: 30

US 93; ON RAMP

Unknown

Over: US 93

4.7 W. TWIN FALLS WCL, Twin Falls, ID

Built 2011 ADT: 5,400

NO DATA ENTERED

Fair

Over: BEAR CREEK

NO DATA ENTERED, Adams, ID

Built 1965 ADT: 50

50234

Fair

Over: COTTONWOOD CK

NO DATA ENTERED, Adams, ID

Built 1966 ADT: 10

NO DATA ENTERED

Fair

Over: E FK WEISER R

NO DATA ENTERED, Adams, ID

Built 1970 ADT: 50

FDR

Fair

Over: WOOD RIVER

12 MILES WEST SNRA HQDS, Blaine, ID

Built 1953 ADT: 50

FDR

Fair

Over: WARM SPRINGS CREEK

11 MILES WEST OF KETCHUM, Blaine, ID

Built 1991 ADT: 50

PINE CREEK ROAD

Fair

Over: GRIMES CREEK

9.5 MI S.W. OF ID CITY, Boise, ID

Built 1947 ADT: 25

FDR

Fair

Over: SOUTH FORK BOISE RIVER

UPPER SO.FK.BOISE RIVER, Camas, ID

Built 1976 ADT: 50

ROAD

Fair

Over: KAY CREEK

NO DATA ENTERED, Clark, ID

Built 1961 ADT: 50

NO DATA ENTERED

Fair

Over: OROGRANDE CREEK

PINE CREEK BRIDGE, Clearwater, ID

Built 1950 ADT: 40

FDR

Fair

Over: EAST FORK SALMON RIVER

22 MILES UP EAST FORK R., Custer, ID

Built 1989 ADT: 50

ROAD

Fair

Over: LUCKY DOG CREEK

NO DATA ENTERED, Fremont, ID

Built 1978 ADT: 50

LAKE CK ROAD 50104

Fair

Over: LAKE CREEK

NO DATA ENTERED, Idaho, ID

Built 1970 ADT: 50

FS ROUTE NO. 805

Fair

Over: WEST FORK EAGLE

W FK EAGLE CREEK, Shoshone, ID

Built 1957 ADT: 50

FS ROUTE NO. 805

Fair

Over: WEST FORK EAGLE CREEK

W FK EAGLE CREEK, Shoshone, ID

Built 1957 ADT: 50

FDR 715

Fair

Over: MEADOW CREEK

VIC 5-LAKES BUTTE TRAIL, Shoshone, ID

Built 1985 ADT: 10

NO DATA ENTERED

Fair

Over: N FK PAYETTE

NO DATA ENTERED, Valley, ID

Built 1958 ADT: 50

ADAMS CK RD 50025

Fair

Over: MANN CREEK

NO DATA ENTERED, Washington, ID

Built 1953 ADT: 50

STC3024;POLLARD LN

Fair

Over: MIDDLETON CANAL

0.6 N. 1.3 E. STAR, Ada, ID

Built 1967 Load: 3.6 t ADT: 1,300

20160

Fair

Over: WARM RIVER

NO DATA ENTERED, Fremont, ID

Built 1985 Load: 4.5 t ADT: 50

IRR BIA RTE 152

Fair

Over: PORTNEUF RIVER

5KM N OF I-86 AT SR30 EXI, Bannock, ID

Built 1960 Load: 5.4 t ADT: 600

OGLE LANE

Fair

Over: LITTLE WEISER RIVER

1.0N 1.1W INDIAN VALLEY, Adams, ID

Built 1982 Load: 6.4 t ADT: 50

AIRPORT ROAD

Fair

Over: BEAR RIVER

2.2 N. 1.1 W. DINGLE, Bear Lake, ID

Built 1916 Load: 6.4 t ADT: 50

GRAVY RIDGE ROAD

Fair

Over: CAMAS CREEK

0.7 N. 11.0 E. DUBOIS, Clark, ID

Built 1956 Load: 6.4 t ADT: 10

SPERRY GRADE RD

Fair

Over: POTLATCH RVR(SPERRY BR)

AT KENDRICK SCL, Nez Perce, ID

Built 1908 Load: 6.4 t ADT: 170

STC2815;WARM SPRNG

Fair

Over: BIG WOOD RIVER

IN KETCHUM;WARM SPRING RD, Blaine, ID

Built 1972 Load: 7.3 t ADT: 5,900

1050 EAST ROAD

Fair

Over: BILLINGSLEY CREEK

0.6 N. 1.1 E. HAGERMAN, Gooding, ID

Built 1950 Load: 7.3 t ADT: 50

N 45TH E

Fair

Over: NORTH FORK WILLOW CR

1.6 S. 1.0 E. UCON, Bonneville, ID

Built 1958 Load: 8.2 t ADT: 2,000

1200 SOUTH ROAD

Fair

Over: CLOVER CREEK

6.9 N. 3.0 W. BLISS, Gooding, ID

Built 1915 Load: 8.2 t ADT: 50

NO DATA ENTERED

Fair

Over: YANKEE FORK

NO DATA ENTERED, Custer, ID

Built 1972 Load: 8.4 t ADT: 50

FS ROUTE NO. 208

Fair

Over: CDA RIVER

2.5 MI FROM SHOSHONE W.C., Shoshone, ID

Built 1952 Load: 8.7 t ADT: 50

650 WEST ROAD

Fair

Over: MILNER GOODING CANAL

6.9 N. 6.4 W. SHOSHONE, Lincoln, ID

Built 1955 Load: 9.1 t ADT: 110

LITTLE CANYON ROAD

Fair

Over: BIG CANYON CREEK

0.4 S. 0.3 E. PECK, Nez Perce, ID

Built 1930 Load: 9.1 t ADT: 190

CARMEN CREEK ROAD

Fair

Over: CARMEN CREEK

NO DATA ENTERED, Lemhi, ID

Built 1961 Load: 10.0 t ADT: 10

2407: WENDELL SHEE

Fair

Over: Twin Falls N. Side Canal

7.2 mi E of ID46, Jerome, ID

Built 1984 Load: 10.4 t ADT: 25

FDR 105

Fair

Over: NF CLEARWATER RIVER

WEITAS CREEK & NF CLW RIV, Clearwater, ID

Built 1937 Load: 10.7 t ADT: 20

MINGO ROAD

Fair

Over: BENCH CANAL

0.2 N. 0.2 E. GRACE, Caribou, ID

Built 2012 Load: 10.9 t ADT: 30

OLD HIGHWAY 95

Fair

Over: SLATE CREEK

0.2 N. SLATE CREEK R.STA, Idaho, ID

Built 1920 Load: 10.9 t ADT: 50

NO DATA ENTERED

Fair

Over: YANKEE FORK

NO DATA ENTERED, Custer, ID

Built 1972 Load: 11.3 t ADT: 50

OLD HWY 91

Fair

Over: PLEASANT VALLEY CREEK

6.9 N. 1.5 W. SPENCER, Clark, ID

Built 1934 Load: 11.8 t ADT: 50

STC 4751;CTTNWD CR

Fair

Over: COYOTE CREEK

3.1 S. 3.0 E. MYRTLE, Nez Perce, ID

Built 1938 Load: 11.8 t ADT: 40

FS ROUTE #231

Fair

Over: PACK RIVER

20 MILES FROM SAMUEL, ID, Boundary, ID

Built 1988 Load: 12.0 t ADT: 50

NO DATA ENTERED

Fair

Over: BIG CREEK

BIG CREEK, Shoshone, ID

Built 1939 Load: 12.0 t ADT: 50

FOREST ROAD 443

Fair

Over: SELWAY RIVER

SELWAY FALLS, Idaho, ID

Built 1934 Load: 12.6 t ADT: 50

FS ROUTE 3099

Fair

Over: CDA RIVER

15.5 MI F/MAGEE R.S., Shoshone, ID

Built 1954 Load: 12.6 t ADT: 50

COUNTY ROAD

Fair

Over: N.FK.SKOOKUMCHUCK CREEK

3.0 S. 4.0 E. WHITEBIRD, Idaho, ID

Built 1965 Load: 12.7 t ADT: 50

Showing 101-150 of 1,742 bridges

Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

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). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.