Total bridges
354
Public highway bridges in Whatcom County
County profile · official public datasets
Whatcom County, WA
354 public highway bridges tracked in the FHWA National Bridge Inventory: 44.1% rated Good, 50.6% Fair, 5.4% Poor.
- 354
- Public bridges
- 44.1%
- Good condition
- 5.4%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Whatcom 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 49%
- lowest Poor share in state
- 5.4%
- Poor-condition share
- 354
- public highway bridges
- 1970
- 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.
Whatcom County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Whatcom County ranks #19 of 39 Washington counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 5.4%). Whatcom County, Washington contains 354 public highway bridges. Roughly 44.1% are rated “Good,” 50.6% “Fair,” and 5.4% “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
44.1%
156 of 354 rated 7-9
Fair condition
50.6%
179 of 354 rated 5-6
Poor condition
5.4%
19 of 354 rated 4 or below
In-state Poor-share rank
#19 of 39
Among Washington counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 354 NBI-tracked bridges by lowest applicable component rating.
Good 44.1% (156)
Fair 50.6% (179)
Poor 5.4% (19)
Whatcom County's Poor-condition bridges carry 74,479 vehicle crossings a day
That is 4% of the county's reported daily bridge traffic on 5.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 3,920 crossings a day against 5,178 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 354 of 354 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
61.9% of Whatcom County's bridges have passed the 50-year mark
219 of the 354 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 44.1% 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 13.4% of the county's Poor-condition bridge traffic
SR 544 over NOOKSACK R OVERFLOW, built 1994, carries 9,956 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 19-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 74,479 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Whatcom County's bridges were built
354 bridges with a recorded construction year, grouped by decade
- 1900s 6
1900–1909
6 bridges
- 1910s 2
1910–1919
2 bridges
- 1920s 8
1920–1929
8 bridges
- 1930s
1930–1939
35 bridges
- 1940s
1940–1949
32 bridges
- 1950s
1950–1959
71 bridges
- 1960s
1960–1969
49 bridges
- 1970s 25
1970–1979
25 bridges
- 1980s 19
1980–1989
19 bridges
- 1990s 25
1990–1999
25 bridges
- 2000s
2000–2009
47 bridges
- 2010s 25
2010–2019
25 bridges
- 2020s 10
2020–2029
10 bridges
What this shows Construction peaked in the 1950s, when 71 of the county's bridges still in the inventory were built, which is 20.1% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year is 1970, 5 years older than the Washington average of 1975.
How Whatcom County compares with Washington's closest counties by inventory size
The 5 Washington counties nearest Whatcom County in number of bridges, with their condition splits. Its 5.4% Poor share is the 3rd-lowest of these 6. Its average build year of 1970 against a peer-group mean of 1975 is 5 years older.
Showing the 5 closest of 38 Washington counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Grays Harbor County | 363 | 48.8% | 41.9% | 9.4% | 1978 |
| Whatcom County (this page) | 354 | 44.1% | 50.6% | 5.4% | 1970 |
| Whitman County | 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 Whatcom 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 Whatcom County, both outside Washington so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside WA (354 bridges here).
- Hendricks County, IN · 355 bridges
- Cameron County, TX · 355 bridges
- Union County, NC · 353 bridges
- Burlington County, NJ · 356 bridges
Similar average build year
Nearest mean year-built outside WA (1970 here).
- Hamilton County, OH · avg 1970 · 783 bridges
- Yavapai County, AZ · avg 1970 · 543 bridges
- Garfield County, OK · avg 1970 · 504 bridges
- San Luis Obispo County, CA · avg 1970 · 401 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (19)
MARTIN RD
PoorOver: ANDERSON CR
00.2 E. ROBERTS RD, Whatcom, WA
Built 1958 Load: 6.3 t ADT: 80
LAKE SAMISH DR N
PoorOver: LAKE SAMISH
S END N LK SAMISH, Whatcom, WA
Built 1953 Load: 9.1 t ADT: 955
JACKSON RD
PoorOver: TERRELL CR
S OF BIRCH BAY DR., Whatcom, WA
Built 1975 Load: 14.6 t ADT: 1,037
GOSHEN RD
PoorOver: ANDERSON CR
00.4 W. SAND RD, Whatcom, WA
Built 1973 Load: 18.5 t ADT: 1,114
MARINE DR
PoorOver: ACCESS RD CREEK OLD RR
0.3 S BENNETT DR., Whatcom, WA
Built 1933 Load: 18.8 t ADT: 7,694
NB SR 539
PoorOver: NOOKSACK R
2.0 N JCT SR 544, Whatcom, WA
Built 1950 Load: 20.0 t ADT: 8,300
SR 547
PoorOver: SAAR CREEK
8.8 N JCT SR 542, Whatcom, WA
Built 1970 Load: 20.1 t ADT: 1,485
MARINE DR
PoorOver: G.N. RR
00.2 E WYNN RD, Whatcom, WA
Built 1940 Load: 20.1 t ADT: 5,805
SR 542
PoorOver: BELL CREEK
3.1 E JCT SR 9, Whatcom, WA
Built 1951 Load: 20.9 t ADT: 5,182
SR 542
PoorOver: CORNELL CREEK
9.7 E JCT SR 547, Whatcom, WA
Built 1931 Load: 22.4 t ADT: 1,903
SR 542
PoorOver: BAGLEY CREEK
26.3 E JCT SR 547, Whatcom, WA
Built 1946 Load: 22.7 t ADT: 621
SR 542
PoorOver: GLACIER CREEK
10.6 E JCT SR 547, Whatcom, WA
Built 1956 Load: 22.7 t ADT: 1,251
ELECTRIC AVENUE
PoorOver: WHATCOM CREEK
0.11 S JCT ALABAMA ST, Whatcom, WA
Built 1959 Load: 22.7 t ADT: 8,500
JAMES STREET
PoorOver: WHATCOM CREEK
0.06 N JCT MEADOR AVE, Whatcom, WA
Built 1936 Load: 22.7 t ADT: 7,000
MEADOR AVENUE
PoorOver: WHATCOM CREEK
0.07 E JCT N STATE ST, Whatcom, WA
Built 1936 Load: 24.9 t ADT: 3,700
SALAKANUM WY
PoorOver: ANDERSON CREEK
00.4 SO OF GOSHEN, Whatcom, WA
Built 1954 Load: 27.5 t ADT: 50
SR 542
PoorOver: OVERFLOW CHANNEL NO 2
0.3 E JCT SR 9, Whatcom, WA
Built 1948 Load: 33.6 t ADT: 9,782
ROAD
PoorOver: THOMPSON CREEK
MP 1.1 RD# 39, Whatcom, WA
Built 1966 Load: 40.0 t ADT: 64
SR 544
PoorOver: NOOKSACK R OVERFLOW
7.6 E JCT SR 539, Whatcom, WA
Built 1994 Load: 89.8 t ADT: 9,956
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.