Total bridges
419
Public highway bridges in Lewis County
County profile · official public datasets
419 public highway bridges tracked in the FHWA National Bridge Inventory: 39.4% rated Good, 56.8% Fair, 3.8% Poor.
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Lewis 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.
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.
According to the Federal Highway Administration's 2024 National Bridge Inventory, Lewis County ranks #10 of 39 Washington counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 3.8%). Lewis County, Washington contains 419 public highway bridges. Roughly 39.4% are rated “Good,” 56.8% “Fair,” and 3.8% “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
419
Public highway bridges in Lewis County
Good condition
39.4%
165 of 419 rated 7-9
Fair condition
56.8%
238 of 419 rated 5-6
Poor condition
3.8%
16 of 419 rated 4 or below
In-state Poor-share rank
#10 of 39
Among Washington counties with 5+ bridges, lower share ranks better
Share of 419 NBI-tracked bridges by lowest applicable component rating.
That is 7.3% of the county's reported daily bridge traffic on 3.8% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 6,382 crossings a day against 2,418 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 418 of 419 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
271 of the 419 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 39.4% 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.
I-5 over LACAMAS CR DREWS PR RD, built 1953, carries 41,665 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 16-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 102,118 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
419 bridges with a recorded construction year, grouped by decade
1910–1919
2 bridges
1920–1929
21 bridges
1930–1939
17 bridges
1940–1949
29 bridges
1950–1959
108 bridges
1960–1969
64 bridges
1970–1979
57 bridges
1980–1989
27 bridges
1990–1999
26 bridges
2000–2009
26 bridges
2010–2019
29 bridges
2020–2029
13 bridges
What this shows Construction peaked in the 1950s, when 108 of the county's bridges still in the inventory were built, which is 25.8% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year is 1969, 6 years older than the Washington average of 1975.
The 5 Washington counties nearest Lewis County in number of bridges, with their condition splits. Its 3.8% Poor share is the 2nd-lowest of these 6. Its average build year of 1969 against a peer-group mean of 1975 is 6 years older.
Showing the 5 closest of 38 Washington counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Snohomish County | 500 | 49% | 47% | 4% | 1980 |
| Pierce County | 472 | 55.3% | 40.5% | 4.2% | 1974 |
| Lewis County (this page) | 419 | 39.4% | 56.8% | 3.8% | 1969 |
| Grays Harbor County | 363 | 48.8% | 41.9% | 9.4% | 1978 |
| Whatcom County | 354 | 44.1% | 50.6% | 5.4% | 1970 |
| Whitman County | 347 | 52.2% | 44.4% | 3.5% | 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 Lewis County's. Source: FHWA National Bridge Inventory, 2024 release.
Two NBI-derived peer sets for Lewis County, both outside Washington so the neighborhoods are not the same-state size table above.
Nearest county inventories outside WA (419 bridges here).
Nearest mean year-built outside WA (1969 here).
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Over: JEFFERSON CREEK
NO DATA ENTERED, Lewis, WA
Over: MILL CR.
1.1 S JCT SR 508, Lewis, WA
Over: DAVIS CREEK
NO DATA ENTERED, Lewis, WA
Over: SILVER CREEK
TAKE RD 47 NORTH OF RANDL, Lewis, WA
Over: WILLAME CREEK
2 1/2 MILES SOUTH OF FS R, Lewis, WA
Over: LUCAS CREEK
5.17 NE NORTH FORK ROAD, Lewis, WA
Over: UNNAMED TRIBUTARY
1.20 JCT MIDDLE FORK ROAD, Lewis, WA
Over: CISPUS RIVER
9.2 MILES SE OF JCT. HWY, Lewis, WA
Over: BLAKESLEE JCT RR
1.6 N JCT SR 507, Lewis, WA
Over: SKATE CREEK
9 MILES NE OF JCT HWY 12, Lewis, WA
Over: STEARNS CREEK
0.07 S JCT 41013, Lewis, WA
Over: NEWAUKUM RIVER
4.5 MILES SE CHEHALIS, Lewis, WA
Over: MID FK NEWAUKUM RIVER
2.5 MILES NW JCT SR 508, Lewis, WA
Over: SKOOKUMCHUCK RIVER
0.7 N JCT SR 507, Lewis, WA
Over: TILTON RIVER
25.0 E JCT I-5, Lewis, WA
Over: LAKE CR.
3.0 SE CURTIS, Lewis, WA
Over: CLEAR FORK COWLITZ
0.7 MILE WEST OF HWY 12 (, Lewis, WA
Over: UNNAMED CREEK
21.8 E PACIFIC CO, Lewis, WA
Over: FRASE CREEK
1.2 N JCT SR 508, Lewis, WA
Over: I-5
3.0 N JCT SR 505, Lewis, WA
Over: I-5
JCT I-5, Lewis, WA
Over: Silver Creek
1.0 East Randle, Lewis, WA
Over: KLICKITAT CREEK
South of Mossyrock Rd E., Lewis, WA
Over: I-5
0.2 N COWLITZ CO, Lewis, WA
Over: DILLENBAUGH CREEK
3.8 N JCT SR 508, Lewis, WA
Over: CURTIS CREEK
3.8 SW WINLOCK, Lewis, WA
Over: OTTER CREEK
3.6 MILES NW OF HWY. 508, Lewis, WA
Over: DEEP CREEK
7.0 W Chehalis, Lewis, WA
Over: LACAMAS CREEK
7.0 E COWLITZ CO, Lewis, WA
Over: NO DATA ENTERED
NO DATA ENTERED, Lewis, WA
Over: TILTON RIVER
28.5 E JCT I-5, Lewis, WA
Over: HANAFORD CREEK
7.5 E. CENTRALIA, Lewis, WA
Over: I-5
1.1 N JCT SR 6, Lewis, WA
Over: DILLENBAUGH CR
6.8 N JCT SR 508, Lewis, WA
Over: S FORK CHEHALIS R
18.0 E PACIFIC CO, Lewis, WA
Over: BERWICK CREEK
1.10 JCT 94000, Lewis, WA
Over: I-5 RAMP
JCT I-5, Lewis, WA
Over: LAUGHINGWATER CREEK
2.6 MILES NORTH OF PARK B, Lewis, WA
Over: OLEQUA CREEK
0.02 W SR 603, Lewis, WA
Over: BENHAM CREEK
16 MILES SOUTH OF HWY 12, Lewis, WA
Over: CEDAR CREEK
10.6 E JCT I-5, Lewis, WA
Over: BIG CREEK
NO DATA ENTERED, Lewis, WA
Over: COON CREEK
3.0 SW TOLEDO, Lewis, WA
Over: US 12
5.0 E JCT SR 7, Lewis, WA
Over: OLEQUA CREEK
4.9 E COWLITZ CO, Lewis, WA
Over: GULCH
3.6 E JCT SR 123, Lewis, WA
Over: I-5
3.7 N JCT SR 508, Lewis, WA
Over: W. FORK WILLAME CREEK
NEAR SKATE CREEK, Lewis, WA
Over: WEST FORK TILTON
NO DATA ENTERED, Lewis, WA
Over: WOODS CREEK
NO DATA ENTERED, Lewis, WA
Read our methodology - how this data is sourced, computed, and verified.
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.