County profile · official public datasets

Skamania County, WA

120 public highway bridges tracked in the FHWA National Bridge Inventory: 45.8% rated Good, 45% Fair, 9.2% Poor.

120
Public bridges
45.8%
Good condition
9.2%
Poor condition

The verdict

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

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

31st
of 39 on Poor share
9.2%
Poor-condition share
120
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.

Skamania County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Skamania County ranks #31 of 39 Washington counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 9.2%). Skamania County, Washington contains 120 public highway bridges. Roughly 45.8% are rated “Good,” 45% “Fair,” and 9.2% “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

120

Public highway bridges in Skamania County

Good condition

45.8%

55 of 120 rated 7-9

Fair condition

45%

54 of 120 rated 5-6

Poor condition

9.2%

11 of 120 rated 4 or below

In-state Poor-share rank

#31 of 39

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

Condition distribution

Share of 120 NBI-tracked bridges by lowest applicable component rating.

Good
45.8% (55)
Fair
45% (54)
Poor
9.2% (11)

Skamania County's Poor-condition bridges carry 10,539 vehicle crossings a day

That is 13.3% of the county's reported daily bridge traffic on 9.2% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 958 crossings a day against 434 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 120 of 120 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

50.8% of Skamania County's bridges have passed the 50-year mark

61 of the 120 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 45.8% 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 45.9% of the county's Poor-condition bridge traffic

SR 14 over HALF BRIDGE, built 1930, carries 4,835 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 11-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 10,539 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Skamania County's bridges were built

120 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1960s, when 21 of the county's bridges still in the inventory were built, which is 17.5% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1974) matches the Washington average (1975).

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

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

The 5 Washington counties nearest Skamania County in number of bridges, with their condition splits. Its 9.2% Poor share is the 6th-lowest of these 6. Its average build year of 1974 against a peer-group mean of 1978 is in line with the group.

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

Bridge inventory size and condition shares for Skamania County and the 5 Washington counties closest to it in inventory size
County Bridges Poor
Franklin County 134 4.5%
Mason County 133 4.5%
Pacific County 120 5.8%
Skamania County (this page) 120 9.2%
Kitsap County 115 0.9%
Jefferson County 99 4%

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

Similar inventory size

Nearest county inventories outside WA (120 bridges here).

Similar average build year

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

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

All 120 Good 55 Fair 54 Poor 11

All bridges (120)

NO DATA ENTERED

Good

Over: MOUSE CREEK

NO DATA ENTERED, Skamania, WA

Built 2006 Load: 56.1 t ADT: 129

NO DATA ENTERED

Good

Over: NINE MILE CREEK

15.3 MILES NORTH OF HWY 1, Skamania, WA

Built 1988 Load: 56.3 t ADT: 10

NO DATA ENTERED

Good

Over: LITTLE WHITE SALMON 1

NO DATA ENTERED, Skamania, WA

Built 1984 Load: 56.7 t ADT: 5

NO DATA ENTERED

Good

Over: TRIBUTARY TO MUDDY RIVER

NO DATA ENTERED, Skamania, WA

Built 2009 Load: 57.2 t ADT: 5

SR 504

Good

Over: EAST CREEK

1.1 E COWLITZ CO, Skamania, WA

Built 1994 Load: 65.3 t ADT: 540

NO DATA ENTERED

Good

Over: POISON CREEK

T8N R9E SEC.18 NW 1/4, Skamania, WA

Built 2000 Load: 66.3 t ADT: 20

NO DATA ENTERED

Good

Over: DRY CREEK

NO DATA ENTERED, Skamania, WA

Built 1981 Load: 93.6 t ADT: 131

SR 14 (FIRST ST.)

Good

Over: KANAKA CREEK

0.2 E COLUMBIA ST., Skamania, WA

Built 1998 Load: 96.9 t ADT: 1,026

NO DATA ENTERED

Good

Over: WEST FORK SWIFT

NO DATA ENTERED, Skamania, WA

Built 1984 Load: 99.9 t ADT: 100

SKAMANIA LANDING R

Poor

Over: BUTLER SLOUGH

0.12 S JCT SR 14, Skamania, WA

Built 1948 Load: 4.5 t ADT: 209

CASCADE AVE EXT.

Poor

Over: KANAKA CREEK

0.1 SOUTH FIRST ST. EAST, Skamania, WA

Built 1920 Load: 15.9 t ADT: 152

NO DATA ENTERED

Poor

Over: LOST CREEK DITCH

7 MILES SOUTHWEST OF MT., Skamania, WA

Built 1986 Load: 16.3 t ADT: 50

SR 14

Poor

Over: HAMILTON CREEK

15.7 E CLARK CO, Skamania, WA

Built 1978 Load: 19.8 t ADT: 4,327

NO DATA ENTERED

Poor

Over: TRAPPER CREEK

14.4 MILES N. OF HWY 14 (, Skamania, WA

Built 1954 Load: 21.8 t ADT: 10

NO DATA ENTERED

Poor

Over: DRY CREEK

ABOUT 11 MILES SW OF TROU, Skamania, WA

Built 1962 Load: 22.7 t ADT: 118

NO DATA ENTERED

Poor

Over: LOST CREEK

ABOUT 10 1/2 MILES SOUTHW, Skamania, WA

Built 1962 Load: 22.7 t ADT: 118

NO DATA ENTERED

Poor

Over: LOST CREEK DITCH

7 MILES SW OF MT. ADAMS R, Skamania, WA

Built 1983 Load: 26.3 t ADT: 50

NO DATA ENTERED

Poor

Over: SWIFT CREEK

ABOUT 4 MILES EAST OF COW, Skamania, WA

Built 1957 Load: 28.1 t ADT: 650

SR 14

Poor

Over: HALF BRIDGE

3.2 E CLARK CO, Skamania, WA

Built 1930 Load: 32.7 t ADT: 4,835

NO DATA ENTERED

Poor

Over: TROUT CREEK 2

NO DATA ENTERED, Skamania, WA

Built 1985 Load: 77.4 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.