Total bridges
419
Public highway bridges in Lewis County
County profile · official public datasets
Lewis County, WA
419 public highway bridges tracked in the FHWA National Bridge Inventory: 39.4% rated Good, 56.8% Fair, 3.8% Poor.
- 419
- Public bridges
- 39.4%
- Good condition
- 3.8%
- Poor condition
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.
- Top 26%
- lowest Poor share in state
- 3.8%
- Poor-condition share
- 419
- public highway bridges
- 1969
- 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.
Lewis County Bridge Snapshot
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.
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
Condition distribution
Share of 419 NBI-tracked bridges by lowest applicable component rating.
Good 39.4% (165)
Fair 56.8% (238)
Poor 3.8% (16)
Lewis County's Poor-condition bridges carry 102,118 vehicle crossings a day
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.
64.7% of Lewis County's bridges have passed the 50-year mark
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.
One structure carries 40.8% of the county's Poor-condition bridge traffic
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.
When Lewis County's bridges were built
419 bridges with a recorded construction year, grouped by decade
- 1910s 2
1910–1919
2 bridges
- 1920s 21
1920–1929
21 bridges
- 1930s 17
1930–1939
17 bridges
- 1940s 29
1940–1949
29 bridges
- 1950s
1950–1959
108 bridges
- 1960s
1960–1969
64 bridges
- 1970s
1970–1979
57 bridges
- 1980s 27
1980–1989
27 bridges
- 1990s 26
1990–1999
26 bridges
- 2000s 26
2000–2009
26 bridges
- 2010s 29
2010–2019
29 bridges
- 2020s 13
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.
How Lewis County compares with Washington's closest counties by inventory size
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.
Nationwide counties with similar inventory size or average build year
Two NBI-derived peer sets for Lewis County, both outside Washington so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside WA (419 bridges here).
- Kay County, OK · 419 bridges
- Taylor County, TX · 419 bridges
- Santa Barbara County, CA · 418 bridges
- Lucas County, OH · 418 bridges
Similar average build year
Nearest mean year-built outside WA (1969 here).
- Cook County, IL · avg 1969 · 1,721 bridges
- Fresno County, CA · avg 1969 · 916 bridges
- Cuyahoga County, OH · avg 1969 · 871 bridges
- Ventura County, CA · avg 1969 · 501 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (16)
NFSR 7003000
PoorOver: EAGLE CREEK
ROAD 70 OFF HWY 7, Lewis, WA
Built 1970 ADT: 50
NFSR 7003000
PoorOver: WEST FORK TILTON
TAKE ROAD 70 OFF HWY 7, Lewis, WA
Built 1970 ADT: 50
CERES HILL ROAD
PoorOver: CHEHALIS RIVER
6.0 W ADNA, Lewis, WA
Built 1948 Load: 8.1 t ADT: 144
CHAMBER WAY
PoorOver: BN RR & N NATL AVE
0.1 E OF INTERSTATE 5, Lewis, WA
Built 1952 Load: 12.7 t ADT: 13,223
DAVISON RD.
PoorOver: TILTON RIVER
1.75 W MORTON, Lewis, WA
Built 1924 Load: 13.6 t ADT: 117
SR 7
PoorOver: S FK TILTON RIVER
2.8 N JCT SR 508, Lewis, WA
Built 1938 Load: 16.5 t ADT: 2,576
SR 7
PoorOver: ABANDONED RAILROAD
2.0 N JCT SR 508, Lewis, WA
Built 1944 Load: 17.8 t ADT: 2,576
I-5
PoorOver: LACAMAS CR DREWS PR RD
0.4 N JCT SR 506, Lewis, WA
Built 1953 Load: 17.8 t ADT: 41,665
US 12
PoorOver: PURCELL CREEK
22.2 E JCT SR 131, Lewis, WA
Built 1971 Load: 21.1 t ADT: 2,360
SR 507
PoorOver: SKOOKUMCHUCK RIVER
2.4 N JCT I-5, Lewis, WA
Built 1928 Load: 22.7 t ADT: 8,699
I-5
PoorOver: COWLITZ RIVER
2.0 N COWLITZ CO, Lewis, WA
Built 1953 Load: 24.5 t ADT: 21,612
US 12
PoorOver: COAL CREEK
20.2 E JCT SR 131, Lewis, WA
Built 1930 Load: 27.2 t ADT: 2,401
KOONTZ RD
PoorOver: I-5
1.0 N JCT US 12, Lewis, WA
Built 1976 Load: 30.5 t ADT: 603
STEVENS CANYON ROA
PoorOver: RAVINE
5.5 miles southwest of jc, Lewis, WA
Built 1952 Load: 31.7 t ADT: 1,375
SR 7
PoorOver: TILTON RIVER
4.1 N JCT SR 508, Lewis, WA
Built 1931 Load: 36.3 t ADT: 2,307
US 12
PoorOver: CLEAR FK OF COWLITZ R
23.1 E JCT SR 131, Lewis, WA
Built 1972 Load: 51.7 t ADT: 2,360
Read our methodology - how this data is sourced, computed, and verified.
Related
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.