County profile · official public datasets

Whitman County, WA

347 public highway bridges tracked in the FHWA National Bridge Inventory: 52.2% rated Good, 44.4% Fair, 3.5% Poor.

347
Public bridges: 52.2%
Good condition: 3.5%
Poor condition

The verdict

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

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

Top 21%
lowest Poor share in state: 3.5%
Poor-condition share: 347
public highway bridges: 1974
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.

Whitman County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Whitman County ranks #8 of 39 Washington counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 3.5%). Whitman County, Washington contains 347 public highway bridges. Roughly 52.2% are rated “Good,” 44.4% “Fair,” and 3.5% “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

347

Public highway bridges in Whitman County

Good condition

52.2%

181 of 347 rated 7-9

Fair condition

44.4%

154 of 347 rated 5-6

Poor condition

3.5%

12 of 347 rated 4 or below

In-state Poor-share rank

#8 of 39

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

Condition distribution

Share of 347 NBI-tracked bridges by lowest applicable component rating.

Good

52.2% (181)

Fair

44.4% (154)

Poor

3.5% (12)

Whitman County's Poor-condition bridges carry 34,980 vehicle crossings a day

That is 10.8% of the county's reported daily bridge traffic on 3.5% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 2,915 crossings a day against 766 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 347 of 347 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

47.6% of Whitman County's bridges have passed the 50-year mark

165 of the 347 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 52.2% 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 27.7% of the county's Poor-condition bridge traffic

US 195 over S FK PALOUSE RIVER, built 1923, carries 9,699 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 12-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 34,980 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

6
1910s

12
1920s

12
1930s

11
1940s

7
1950s

12
1960s

59
1970s

95
1980s

32
1990s

41
2000s

41
2010s

16
2020s

3

What this shows Construction peaked in the 1970s, when 95 of the county's bridges still in the inventory were built, which is 27.4% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1974) matches the Washington average (1975).

How Whitman County compares with Washington's closest counties by inventory size

The 5 Washington counties nearest Whitman County in number of bridges, with their condition splits. Its 3.5% Poor share is the 2nd-lowest of these 6. Its average build year of 1974 against a peer-group mean of 1974 is in line with the group.

Showing the 5 closest of 38 Washington counties eligible for comparison.

Bridge inventory size and condition shares for Whitman County and the 5 Washington counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Grays Harbor County	363	48.8%	41.9%	9.4%	1978
Whatcom County	354	44.1%	50.6%	5.4%	1970
Whitman County (this page)	347	52.2%	44.4%	3.5%	1974
Kittitas County	308	39%	50.6%	10.4%	1973
Spokane County	307	51.1%	42%	6.8%	1978
Grant County	306	63.7%	33.7%	2.6%	1973

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

Similar inventory size

Nearest county inventories outside WA (347 bridges here).

Fillmore County, MN · 348 bridges
Cumberland County, NC · 348 bridges
Mahoning County, OH · 348 bridges
Cumberland County, PA · 348 bridges

Similar average build year

Nearest mean year-built outside WA (1974 here).

Knox County, TN · avg 1974 · 588 bridges
Summit County, OH · avg 1974 · 563 bridges
Onondaga County, NY · avg 1974 · 472 bridges
Orange County, NY · avg 1974 · 472 bridges

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

All 347 Good 181 Fair 154 Poor 12

Good-condition bridges (181)

Sort:

Whitman County Bridge Snapshot

Condition distribution

Whitman County's Poor-condition bridges carry 34,980 vehicle crossings a day

47.6% of Whitman County's bridges have passed the 50-year mark

One structure carries 27.7% of the county's Poor-condition bridge traffic

How Whitman County compares with Washington'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 (181)

SR 271

SR 195

WARNER/1100

SAND/9060

D STREET

LITTLE ALKALI/8150

BARTLET STREET

KELSEY/3880

UNION FLAT/9020

FARMINGTON/1000

JOHNSON/9050

BIG ALKALI/7005

ALTERGOTT/2420

3RD STREET

JORDAN-KNOTT/4010

SR 127

GUSKE/6120

LNG JN MORASH/6020

11TH STREET

SEN.EUGENE PRINCE

THORN CREEK/3380

BLAIR STREET

SR 26

CACHE CREEK/3590

SR 27

ORAL SMITH/2590

OLD SR #26/7205

PARVIN/5000

GRDN HAMILTON/4510

VIOLA/ 5190

WHELAN/5515

SUNSET/3360

PARVIN/5000

ELBERTON/2400

WIEDRICH/6050

WILTZIUS/3030

RYDE RD. 1450

SQUAW/3660

ST JOHN / 1090

SAND/9060

ST JN GUN CLB/4610

WAWAWAI/9000

LOOMIS AVE.

F STREET

SUNSET/3360

LITTLE GSE DM/7010

SUNSET/3360

KACKMAN/4210

APP UNIONTN E/9410

STEVICK/8220

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