County profile · official public datasets

Power County, ID

70 public highway bridges tracked in the FHWA National Bridge Inventory: 28.6% rated Good, 68.6% Fair, 2.9% Poor.

70
Public bridges: 28.6%
Good condition: 2.9%
Poor condition

The verdict

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

Power County pairs a better-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.

Top 30%
lowest Poor share in state: 2.9%
Poor-condition share: 70
public highway bridges: 1973
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.

Power County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Power County ranks #13 of 44 Idaho counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.9%). Power County, Idaho contains 70 public highway bridges. Roughly 28.6% are rated “Good,” 68.6% “Fair,” and 2.9% “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

Public highway bridges in Power County

Good condition

28.6%

20 of 70 rated 7-9

Fair condition

68.6%

48 of 70 rated 5-6

Poor condition

2.9%

2 of 70 rated 4 or below

In-state Poor-share rank

#13 of 44

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

Condition distribution

Share of 70 NBI-tracked bridges by lowest applicable component rating.

Good

28.6% (20)

Fair

68.6% (48)

Poor

2.9% (2)

Power County's Poor-condition bridges carry 2,800 vehicle crossings a day

That is 1.5% of the county's reported daily bridge traffic on 2.9% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,400 crossings a day against 3,126 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 70 of 70 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

55.7% of Power County's bridges have passed the 50-year mark

39 of the 70 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 28.6% 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 53.6% of the county's Poor-condition bridge traffic

I 86B ROCKLAND IC over I 86 EB-WB;ROCKLAND IC, built 1959, carries 1,500 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 2-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 2,800 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1930s

2
1940s

1
1950s

10
1960s

17
1970s

14
1980s

20
1990s

2
2000s

1
2010s

2
2020s

1

What this shows Construction peaked in the 1980s, when 20 of the county's bridges still in the inventory were built, which is 28.6% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1973, 6 years older than the Idaho average of 1979.

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

The 5 Idaho counties nearest Power County in number of bridges, with their condition splits. Its 2.9% Poor share is the 3rd-lowest of these 6. Its average build year of 1973 against a peer-group mean of 1975 is in line with the group.

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

Bridge inventory size and condition shares for Power County and the 5 Idaho counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Gooding County	80	16.3%	76.3%	7.5%	1965
Nez Perce County	71	28.2%	69%	2.8%	1977
Power County (this page)	70	28.6%	68.6%	2.9%	1973
Minidoka County	66	28.8%	71.2%	0%	1983
Payette County	65	13.8%	81.5%	4.6%	1970
Camas County	61	27.9%	62.3%	9.8%	1978

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 Power 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 Power County, both outside Idaho so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside ID (70 bridges here).

Jefferson County, FL · 70 bridges
Jasper County, GA · 70 bridges
Treutlen County, GA · 70 bridges
Turner County, GA · 70 bridges

Similar average build year

Nearest mean year-built outside ID (1973 here).

Jefferson County, AL · avg 1973 · 1,068 bridges
Erie County, NY · avg 1973 · 906 bridges
Davidson County, TN · avg 1973 · 832 bridges
Lancaster County, PA · avg 1973 · 801 bridges

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

All 70 Good 20 Fair 48 Poor 2

All bridges (70)

Sort:

Power County Bridge Snapshot

Condition distribution

Power County's Poor-condition bridges carry 2,800 vehicle crossings a day

55.7% of Power County's bridges have passed the 50-year mark

One structure carries 53.6% of the county's Poor-condition bridge traffic

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

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

All bridges (70)

KING LANE

NEIBAUR ROAD

MICHAUD ROAD

STC 1718;ARBON VLY

IRR BIA RTE 182

OSBORN LOOP

NELSON LANE

HOUTZ CANYON RD

STC5695;RAMSEY RD

REGISTER RD

FRONTAGE ROAD

RAINBOW ROAD

FRONTAGE ROAD

US 30 ;W. POKY IC

BARKDULL RD

I 86 EBL

I 86 EBL

I 86 WBL

HALLING ROAD

I 86 EBL

I 86 EBL

I 86 WBL

I 86 EBL

I 86 WBL

I 86 EBL

I 86 WBL

LANDING ROAD

FLINT ROAD

BATISTE ROAD

KUPER ROAD

E. COUNTY ROAD

I 86 EBL

I 86 WBL

I 86 WBL

I 86 EBL

I 86 WBL

I 86B

I 86 EBL

I 86 WBL

IRR BIA RTE 187

ESTEP LANE

I 86 WBL & EBL

ROCK CREEK ROAD

MASSACRE ROCKS RD

SH 39 SBL

I 86 & RAMPS

FRONTAGE ROAD

STC 1753;ARBON VLY

STC 1718;ARBON VLY

I 86 EBL

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