County profile · official public datasets

Adams County, ID

87 public highway bridges tracked in the FHWA National Bridge Inventory: 32.2% rated Good, 57.5% Fair, 10.3% Poor.

87
Public bridges
32.2%
Good condition
10.3%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Adams County posts a higher-than-median Poor-condition share among rated counties in the state across rated county bridge inventory.

42nd
of 44 on Poor share
10.3%
Poor-condition share
87
public highway bridges
1975
avg year built

Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.

Adams County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Adams County ranks #42 of 44 Idaho counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 10.3%). Adams County, Idaho contains 87 public highway bridges. Roughly 32.2% are rated “Good,” 57.5% “Fair,” and 10.3% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.

Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.

Source: FHWA National Bridge Inventory. See methodology for full definitions.

Total bridges

87

Public highway bridges in Adams County

Good condition

32.2%

28 of 87 rated 7-9

Fair condition

57.5%

50 of 87 rated 5-6

Poor condition

10.3%

9 of 87 rated 4 or below

In-state Poor-share rank

#42 of 44

Among Idaho counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 87 NBI-tracked bridges by lowest applicable component rating.

Good
32.2% (28)
Fair
57.5% (50)
Poor
10.3% (9)

Adams County's Poor-condition bridges carry 443 vehicle crossings a day

That is 1.1% of the county's reported daily bridge traffic on 10.3% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 49 crossings a day against 665 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.

Computed over the 87 of 87 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

52.9% of Adams County's bridges have passed the 50-year mark

46 of the 87 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 32.2% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.

Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.

One structure carries 22.6% of the county's Poor-condition bridge traffic

OLD HORNET ROAD over HORNET CREEK, built 1949, carries 100 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 9-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 443 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Adams County's bridges were built

87 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1960s, when 16 of the county's bridges still in the inventory were built, which is 18.4% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1975) matches the Idaho average (1979).

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

How Adams County compares with Idaho's closest counties by inventory size

The 5 Idaho counties nearest Adams County in number of bridges, with their condition splits. Its 10.3% Poor share is the 6th-lowest of these 6. Its average build year of 1975 against a peer-group mean of 1976 is in line with the group.

Showing the 5 closest of 43 Idaho counties eligible for comparison.

Bridge inventory size and condition shares for Adams County and the 5 Idaho counties closest to it in inventory size
County Bridges Poor
Boise County 88 5.7%
Clearwater County 88 5.7%
Adams County (this page) 87 10.3%
Boundary County 83 9.6%
Gooding County 80 7.5%
Madison County 80 0%

Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Adams County's. Source: FHWA National Bridge Inventory, 2024 release.

Nationwide counties with similar inventory size or average build year

Two NBI-derived peer sets for Adams County, both outside Idaho so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside ID (87 bridges here).

Similar average build year

Nearest mean year-built outside ID (1975 here).

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 87 Good 28 Fair 50 Poor 9

Good-condition bridges (28)

ROAD TO CAMPGROUND

Good

Over: EAST FORK WEISER RIVER

NO DATA ENTERED, Adams, ID

Built 2005 Load: 21.4 t ADT: 50

SHAW LANE

Good

Over: M.FK.WEISER RIVER

5.0 S. COUNCIL, Adams, ID

Built 1951 Load: 22.7 t ADT: 10

JACKSON CREEK ROAD

Good

Over: JOHNSON CREEK

1.5 S. 5.2 W. COUNCIL, Adams, ID

Built 2001 Load: 23.6 t ADT: 50

NO DATA ENTERED

Good

Over: GOOSE CREEK

NO DATA ENTERED, Adams, ID

Built 1963 Load: 24.3 t ADT: 50

MUNDY GULCH ROAD

Good

Over: LITTLE WEISER RIVER

0.7 W. INDIAN VALLEY, Adams, ID

Built 1981 Load: 25.4 t ADT: 100

NO DATA ENTERED

Good

Over: GOOSE CREEK

NO DATA ENTERED, Adams, ID

Built 1963 Load: 27.9 t ADT: 50

NFSR 50172

Good

Over: E FK WEISER RIVER

NO DATA ENTERED, Adams, ID

Built 2013 Load: 28.5 t ADT: 50

COTTONWOOD ROAD

Good

Over: COTTONWOOD CREEK

3.3 S. 2.8 E. COUNCIL, Adams, ID

Built 2022 Load: 33.4 t ADT: 80

HUBBARD ROAD

Good

Over: LITTLE SALMON RIVER

0.8 W. NEW MEADOWS, Adams, ID

Built 2004 Load: 34.5 t ADT: 20

RIDGE ROAD

Good

Over: W.FK.WEISER RIVER

6.2 N. 1.1 W. COUNCIL, Adams, ID

Built 2022 Load: 35.6 t ADT: 70

US 95

Good

Over: COTTONWOOD CREEK

2.6 S. COUNCIL CL, Adams, ID

Built 2017 Load: 36.3 t ADT: 2,900

FALL CREEK ROAD

Good

Over: MIDDLE FK WEISER RIVER

5.9 S 3.1 E COUNCIL, Adams, ID

Built 2022 Load: 36.6 t ADT: 10

WILDHORSE RD

Good

Over: BEAR CREEK

4.6 S 2.5 W BEAR, Adams, ID

Built 2011 Load: 36.9 t ADT: 30

LITTLE WEISER

Good

Over: LITTLE WEISER RIVER

LITTLE WEISER BRIDGE, Adams, ID

Built 2004 Load: 37.6 t ADT: 30

NF ROAD 105

Good

Over: INDIAN CREEK

2.4 N 2.8 E CUPRUM, Adams, ID

Built 2010 Load: 40.8 t ADT: 80

NO DATA ENTERED

Good

Over: EAST FORK WEISER RIVER

NO DATA ENTERED, Adams, ID

Built 1963 Load: 40.8 t ADT: 50

US 95

Good

Over: WEISER RIVER;TAMARACK BR

6.4 W. NEW MEADOWS WCL, Adams, ID

Built 2017 Load: 43.4 t ADT: 2,300

US 95

Good

Over: MUD CREEK

3.3 W. NEW MEADOWS WCL, Adams, ID

Built 2017 Load: 43.7 t ADT: 2,600

STC3892;INDIAN VLY

Good

Over: LITTLE WEISER RIVER

1.2S INDIAN VALLEY, Adams, ID

Built 2002 Load: 44.5 t ADT: 130

FARRELL ROAD

Good

Over: W.BR.GOOSE CREEK

0.5 E. NEW MEADOWS, Adams, ID

Built 1991 Load: 45.4 t ADT: 80

US 95

Good

Over: LITTLE SALMON RIVER

13.9 N. NEW MEADOWS NCL, Adams, ID

Built 2019 Load: 48.3 t ADT: 3,000

NF ROAD 105

Good

Over: INDIAN CREEK

1.6 N 2.2 E CUPRUM, Adams, ID

Built 1980 Load: 49.0 t ADT: 80

NF ROAD 105

Good

Over: INDIAN CREEK

1.2 N 1.8 E CUPRUM, Adams, ID

Built 1980 Load: 49.0 t ADT: 80

US 95

Good

Over: LITTLE SALMON RIVER

0.2 W. NEW MEADOWS WCL, Adams, ID

Built 2021 Load: 52.8 t ADT: 3,700

MIDDLE FORK ROAD

Good

Over: M.FK.WEISER RIVER

4.3 S. 2.0 W. COUNCIL, Adams, ID

Built 1977 Load: 53.5 t ADT: 10

FRUITVALE ROAD

Good

Over: WEISER RIVER

2.9 S. 2.7 W. EVERGREEN, Adams, ID

Built 2000 Load: 53.5 t ADT: 80

US 95

Good

Over: LESTER CREEK

2.0 S. COUNCIL, Adams, ID

Built 2017 Load: 54.4 t ADT: 2,900

UPPER DALE ROAD

Good

Over: HORNET CREEK

7.7 N 8.4 W COUNCIL, Adams, ID

Built 1999 Load: 69.9 t ADT: 20

Read our methodology - how this data is sourced, computed, and verified.

Related

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Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges

Every figure on PlainBridges 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. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.