County profile · official public datasets

Latah County, ID

115 public highway bridges tracked in the FHWA National Bridge Inventory: 35.7% rated Good, 64.3% Fair, 0% Poor.

115
Public bridges: 35.7%
Good condition: 0%
Poor condition

The verdict

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

Latah County posts a top-10% lowest Poor-condition share among rated counties in the state across mid-size county bridge inventory.

Top 7%
lowest Poor share in state: 0%
Poor-condition share: 115
public highway bridges: 1978
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.

Latah County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Latah County ranks #3 of 44 Idaho counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 0%). Latah County, Idaho contains 115 public highway bridges. Roughly 35.7% are rated “Good,” 64.3% “Fair,” and 0% “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

115

Public highway bridges in Latah County

Good condition

35.7%

41 of 115 rated 7-9

Fair condition

64.3%

74 of 115 rated 5-6

Poor condition

0 of 115 rated 4 or below

In-state Poor-share rank

#3 of 44

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

Condition distribution

Share of 115 NBI-tracked bridges by lowest applicable component rating.

Good

35.7% (41)

Fair

64.3% (74)

Poor

0% (0)

45.2% of Latah County's bridges have passed the 50-year mark

52 of the 115 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 35.7% 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.

1910s

2
1930s

8
1940s

6
1950s

12
1960s

8
1970s

29
1980s

9
1990s

13
2000s

10
2010s

11
2020s

7

What this shows Construction peaked in the 1970s, when 29 of the county's bridges still in the inventory were built, which is 25.2% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1978) matches the Idaho average (1979).

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

The 5 Idaho counties nearest Latah County in number of bridges, with their condition splits. Its 0% Poor share is the 2nd-lowest of these 6. Its average build year of 1978 against a peer-group mean of 1980 is in line with the group.

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

Bridge inventory size and condition shares for Latah County and the 5 Idaho counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Twin Falls County	126	12.7%	84.1%	3.2%	1973
Bannock County	124	33.1%	62.1%	4.8%	1981
Cassia County	116	15.5%	84.5%	0%	1984
Latah County (this page)	115	35.7%	64.3%	0%	1978
Lemhi County	112	53.6%	40.2%	6.3%	1988
Jerome County	110	10%	80.9%	9.1%	1974

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

Similar inventory size

Nearest county inventories outside ID (115 bridges here).

Alachua County, FL · 115 bridges
Walton County, GA · 115 bridges
Whitley County, IN · 115 bridges
Carver County, MN · 115 bridges

Similar average build year

Nearest mean year-built outside ID (1978 here).

Orange County, CA · avg 1978 · 1,164 bridges
Sumner County, KS · avg 1978 · 659 bridges
Allen County, IN · avg 1978 · 613 bridges
Livingston County, IL · avg 1978 · 579 bridges

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

All 115 Good 41 Fair 74 Poor 0

Good-condition bridges (41)

Sort:

Latah County Bridge Snapshot

Condition distribution

45.2% of Latah County's bridges have passed the 50-year mark

How Latah 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

Good-condition bridges (41)

FDR 377D

STC 4771;SOUTHWICK

FDR 381

BLAINE ST

STC 7834;LINE ST

STC4805;CEDR RDG R

STC 4792;CHESTNUT

PARK ROAD; NF-1963

OLD RIVER ROAD

MILL ROAD

EISENHOWER STREET

W. 7TH STREET

GENESEE-TROY ROAD

FDR 447

BLUE HERON LANE

SOUTH RIVER ROAD

SH 9

PARK ROAD

SH 6

SH 9

VIOLA ROAD

US 95

SH 8

STC 7664;E. 6TH ST

US 95

S4795;GNSEE-JLETTA

NO DATA ENTERED

US 95

VIOLA MAIN STREET

SH 3

STC4790;THORN CRK

SH 3

FDR 447

S4808;ROBINSON PK

STADIUM DR

W. 6TH STREET

SMA7724; JOSEPH ST

STADIUM DR

SH 6

SMA 7674;MTN VIEW

SMA 7754;D ST

Related