Whatcom County, WA

358 public highway bridges

Whatcom County Bridge Snapshot

Whatcom County, Washington contains 358 public highway bridges in the FHWA National Bridge Inventory. Roughly 38.3% are rated “Good,” 46.6% “Fair,” 5.3% “Poor,” and 5.3% are classified as structurally deficient — the federal designation for spans whose deck, superstructure, or substructure has been rated 4 or below on the 0–9 NBI scale. Structurally deficient does not mean unsafe to cross; it means the bridge is on the priority list for repair or replacement.

Inspections in WA are conducted by certified engineers from the state Department of Transportation on a 24-month cycle, and results are reported back to the FHWA each spring. The list below shows every NBI-tracked bridge in the county, sorted by inventory load rating. Use the “Sort by” controls to surface the lowest-rated spans first, and click any row for full inspection history, traffic counts, and condition trends.

Source: FHWA National Bridge Inventory. See methodology for full definitions.

358

Total Bridges

38.3%

Good

5.3%

Poor

5.3%

Structurally Deficient

Condition Distribution

Good

38.3% (137)

Fair

46.6% (167)

Poor

5.3% (19)

SD

5.3% (19)

All Bridges (358)

Sort:

I-5 OFF RAMP

Over: SR 539, CREEK

JCT I-5, Whatcom, WA

Built 1988 ADT: 38,656

I-5

Over: IOWA ST

3.1 N JCT SR 11, Whatcom, WA

I-5

Over: SR 539 MERIDIAN ST

JCT I-5, Whatcom, WA

Built 1958 ADT: 38,656

I-5

Over: SR 539 MERIDIAN ST

JCT I-5, Whatcom, WA

Built 1958 ADT: 38,656

ALABAMA ST

Over: I-5

3.5 N JCT SR 11, Whatcom, WA

Built 1958 ADT: 76,839

I-5

Over: NORTHWEST AVE

0.8 N JCT SR 539, Whatcom, WA

I-5

Over: NORTHWEST AVE

0.8 N JCT SR 539, Whatcom, WA

Built 1958 ADT: 49,138

PEDESTRIAN

Over: I-5

3.7 N JCT SR 11, Whatcom, WA

Built 1959 ADT: 76,839

PEDESTRIANS

Over: I-5

3.9 N JCT SR 11, Whatcom, WA

Built 1960 ADT: 57,095

PORTAL WAY

Over: I-5

9.0 N JCT SR 539, Whatcom, WA

Built 1961 ADT: 36,168

MITCHELL AVE

Over: I-5

0.4 N JCT SR 543, Whatcom, WA

Built 1963 ADT: 3,830

H ST

Over: I-5

0.7 N JCT SR 543, Whatcom, WA

Built 1962 ADT: 3,830

SR 548/GRANDVIEW

Over: I-5

9.7 N JCT SR 539, Whatcom, WA

Built 1962 ADT: 22,338

CUSTER SCHOOL RD

Over: I-5, RAMP

3.0 N JCT SR 548, Whatcom, WA

Built 1962 ADT: 27,450

BIRCH BAY-LYNDEN R

Over: I-5

4.3 N JCT SR 548, Whatcom, WA

Built 1961 ADT: 14,164

LOOMIS TRAIL RD

Over: I-5

5.6 N JCT SR 548, Whatcom, WA

Built 1963 ADT: 15,108

I-5

Over: N-W RAMP I-5

8.2 N JCT SR 548, Whatcom, WA

Built 1962 ADT: 12,522

SAMISH WAY

Over: I-5

3.6 N SKAGIT CO, Whatcom, WA

Built 1962 ADT: 47,259

I-5

Over: SR 11 (CONNELLY AVE)

7.2 N SKAGIT CO, Whatcom, WA

Built 1962 ADT: 11,327

I-5

Over: SR 11 (CONNELLY AVE)

7.2 N SKAGIT CO, Whatcom, WA

Built 1962 ADT: 11,327

HUGHES AVE

Over: I-5

8.5 N JCT SR 548, Whatcom, WA

Built 1963 ADT: 12,522

I-5

Over: SR 548 (D ST)

13.8 W JCT I-5, Whatcom, WA

Built 1963 ADT: 5,196

I-5

Over: SR 548 (D ST)

13.8 W JCT I-5, Whatcom, WA

Built 1963 ADT: 5,196

MAIN STREET

Over: I-5

6.3 N JCT SR 539, Whatcom, WA

Built 1968 ADT: 37,728

SR 543

Over: I-5

9.2 N JCT SR 548, Whatcom, WA

Built 1971 ADT: 3,830

SMITH RD

Over: I-5

5.3 N JCT SR 539, Whatcom, WA

Built 1972 ADT: 47,799

SLATER RD

Over: I-5

3.9 N JCT SR 539, Whatcom, WA

Built 1972 ADT: 43,730

BAKERVIEW RD

Over: I-5

1.5 N JCT SR 539, Whatcom, WA

Built 1975 ADT: 42,845

CITY ST TO I-5 NB

Over: I-5

1.7 N JCT SR 539, Whatcom, WA

Built 1976 ADT: 42,845

SR 542 (SUNSET DR)

Over: I-5

4.1 N JCT SR 11, Whatcom, WA

Built 1996 ADT: 57,095

D STREET

Over: SR 543 NORTHBOUND

0.8 N JCT I-5, Whatcom, WA

Built 2007 ADT: 5,649

D STREET

Over: SR 543 SOUTHBOUND

0.8 N JCT I-5, Whatcom, WA

Built 2007 ADT: 5,649

BN RAILROAD

Over: E. MAIN ST

AT HOVANDER RD, Whatcom, WA

Built 1960 ADT: 3,000

Pedestrian Pathway

Over: Alabama Street

0.5 E JCT YEW ST, Whatcom, WA

Built 2002 ADT: 1,650

SAMISH WAY

Over: I-5

1.4 N JCT SR 11, Whatcom, WA

Built 2000 ADT: 47,405

ROAD

Over: SLATE CREEK

MP 1.3 RD 3070, Whatcom, WA

Built 2007 ADT: 50

ELDRIDGE AVENUE

Over: SQUALLICUM CRK-CMSTP&P R

0.07 NW JCT MADRONA ST, Whatcom, WA

Built 1937 Load: 9.1 t ADT: 6,400

GOOSEBERRY SPUR

Over: HALE PASSAGE

2. SW OF CAGEY RD., Whatcom, WA

Built 1950 Load: 10.9 t ADT: 1,300

SUMAS AVE

Over: JOHNSON CR

0.15 N FRONT ST, Whatcom, WA

Built 1970 Load: 11.3 t ADT: 926

BAKER LK RD

Over: ROCKY CR

0.52 N SKAGIT LINE, Whatcom, WA

Built 1956 Load: 11.7 t ADT: 917

SR 548

Over: DAKOTA CREEK

11.5 W JCT I-5, Whatcom, WA

Built 1930 Load: 11.8 t ADT: 7,586

NB SR 539

Over: NOOKSACK R OVERFLOW

2.6 N JCT SR 544, Whatcom, WA

Built 1950 Load: 12.3 t ADT: 8,300

MACK RD

Over: SUMAS RIVER

00.2 W OAT COLES RD, Whatcom, WA

Built 1932 Load: 12.7 t ADT: 106

HILLSIDE RD

Over: SIGITOWITZ CREEK

01.0 S.W. POTTER RD, Whatcom, WA

Built 1950 Load: 13.6 t ADT: 250

GILLIES RD

Over: SUMAS RIVER

00.1 S OF ALM RD., Whatcom, WA

Built 1947 Load: 13.9 t ADT: 263

TURKINGTON RD

Over: JONES CR

00.5 W VALLEY HWY, Whatcom, WA

Built 1951 Load: 14.5 t ADT: 338

HOLLY STREET

Over: WHATCOM CREEK

.3 W OF CITY HALL, Whatcom, WA

Built 1922 Load: 14.5 t ADT: 8,700

ALDRICH RD

Over: TEN MILE CR.

0.2 S W HEMMI RD, Whatcom, WA

Built 1924 Load: 14.6 t ADT: 1,192

ALM RD

Over: SUMAS RIVER

0.4 W GLLES, Whatcom, WA

Built 1947 Load: 14.9 t ADT: 291

NELSON RD

Over: BLACK SLOUGH

00.5 E VALLEY HWY, Whatcom, WA

Built 1934 Load: 15.4 t ADT: 80

Read our methodology — how this data is sourced, computed, and verified.

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Data sourced from official U.S. government datasets. See our methodology for details. Retrieved and formatted by PlainBridges Editorial

Reviewed byPlainbridges Editorial, Plain Bridges Editorial Team · June 5, 2026