Total bridges
326
Public highway bridges in Washington County
County profile · official public datasets
Washington County, OR
326 public highway bridges tracked in the FHWA National Bridge Inventory: 35.6% rated Good, 62% Fair, 2.5% Poor.
- 326
- Public bridges
- 35.6%
- Good condition
- 2.5%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Washington County pairs a better-than-median Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
- Top 31%
- lowest Poor share in state
- 2.5%
- Poor-condition share
- 326
- public highway bridges
- 1983
- 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.
Washington County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Washington County ranks #11 of 36 Oregon counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.5%). Washington County, Oregon contains 326 public highway bridges. Roughly 35.6% are rated “Good,” 62% “Fair,” and 2.5% “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
35.6%
116 of 326 rated 7-9
Fair condition
62%
202 of 326 rated 5-6
Poor condition
2.5%
8 of 326 rated 4 or below
In-state Poor-share rank
#11 of 36
Among Oregon counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 326 NBI-tracked bridges by lowest applicable component rating.
Good 35.6% (116)
Fair 62% (202)
Poor 2.5% (8)
Washington County's Poor-condition bridges carry 54,681 vehicle crossings a day
That is 1.1% of the county's reported daily bridge traffic on 2.5% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 6,835 crossings a day against 10,980 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 326 of 326 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
38.3% of Washington County's bridges have passed the 50-year mark
125 of the 326 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 35.6% 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 35.6% of the county's Poor-condition bridge traffic
ALLEN BLVD over HWY 144, built 1981, carries 19,471 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 8-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 54,681 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Washington County's bridges were built
326 bridges with a recorded construction year, grouped by decade
- 1920s 5
1920–1929
5 bridges
- 1930s 6
1930–1939
6 bridges
- 1940s 10
1940–1949
10 bridges
- 1950s 24
1950–1959
24 bridges
- 1960s
1960–1969
41 bridges
- 1970s
1970–1979
68 bridges
- 1980s
1980–1989
38 bridges
- 1990s
1990–1999
37 bridges
- 2000s
2000–2009
57 bridges
- 2010s 25
2010–2019
25 bridges
- 2020s 15
2020–2029
15 bridges
What this shows Construction peaked in the 1970s, when 68 of the county's bridges still in the inventory were built, which is 20.9% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year is 1983, 8 years newer than the Oregon average of 1975.
How Washington County compares with Oregon's closest counties by inventory size
The 5 Oregon counties nearest Washington County in number of bridges, with their condition splits. Its 2.5% Poor share is the 3rd-lowest of these 6. Its average build year of 1983 against a peer-group mean of 1975 is 8 years newer.
Showing the 5 closest of 35 Oregon counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Jackson County | 401 | 34.2% | 64.3% | 1.5% | 1976 |
| Marion County | 373 | 21.2% | 74.5% | 4.3% | 1971 |
| Clackamas County | 367 | 31.1% | 66.5% | 2.5% | 1975 |
| Washington County (this page) | 326 | 35.6% | 62% | 2.5% | 1983 |
| Umatilla County | 321 | 31.5% | 64.5% | 4% | 1973 |
| Coos County | 254 | 40.9% | 55.9% | 3.1% | 1978 |
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 Washington 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 Washington County, both outside Oregon so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside OR (326 bridges here).
- Miami County, KS · 326 bridges
- Montgomery County, KS · 326 bridges
- Merrimack County, NH · 326 bridges
- St. Clair County, MI · 327 bridges
Similar average build year
Nearest mean year-built outside OR (1983 here).
- Dallas County, TX · avg 1983 · 3,230 bridges
- Bexar County, TX · avg 1983 · 2,342 bridges
- Sedgwick County, KS · avg 1983 · 1,333 bridges
- Will County, IL · avg 1983 · 649 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
All bridges (326)
Cornelius Pass Rd
FairOver: Hwy 47 (US 26)
11.9 MI W OF PORTLAND CC, Washington, OR
Built 1988 Load: 27.9 t ADT: 32,418
SPRING HILL RD
FairOver: TUALATIN RIVER
004 MI S R/R ING, Washington, OR
Built 1972 Load: 27.9 t ADT: 1,274
S.W. HALL BLVD
FairOver: BEAVERTON CREEK
003 MI N TV HWY, Washington, OR
Built 1969 Load: 27.9 t ADT: 13,469
OR 6 (HWY 037)
FairOver: EB HWY 047
0.2 MI SW HWY 047 JCT, Washington, OR
Built 1954 Load: 28.1 t ADT: 4,121
S W OAK STREET
FairOver: ASH CREEK
001 MI W HALL BLVD, Washington, OR
Built 1972 Load: 28.1 t ADT: 2,523
Hwy 29
FairOver: Gales Creek Overflow
5.4 MI W HILLSBORO WCL, Washington, OR
Built 1975 Load: 28.2 t ADT: 13,003
GOLF COURSE ROAD
FairOver: TUALATIN RIVER
106 MI S HWY 8, Washington, OR
Built 1974 Load: 28.5 t ADT: 5,074
SW MURRAY BLVD NB
FairOver: BNRR & TERMAN ROAD
005 MI N HWY 8, Washington, OR
Built 1999 Load: 29.0 t ADT: 8,841
OR 6 (Hwy 037)
FairOver: Hwy 102
2.5 MI W OF HWY 47 JCT, Washington, OR
Built 1956 Load: 29.8 t ADT: 8,032
US 26 (Hwy 047)
FairOver: Hwy 29 Canyon Road
3.7 MI W OF PORTLAND CC, Washington, OR
Built 2004 Load: 29.8 t ADT: 105,119
WEST SHORE DRIVE
FairOver: SCOGGINS CREEK
0080 MI W SCOGGIN VALLEY, Washington, OR
Built 1974 Load: 29.9 t ADT: 382
UPPER BOONES FERRY
FairOver: I-5 (HWY 001)
1.5 MI N OF TUALATIN RV, Washington, OR
Built 1975 Load: 30.5 t ADT: 13,860
CEDAR CANYON ROAD
FairOver: SMALL STREAM
015 MI W HWY 47, Washington, OR
Built 1996 Load: 30.5 t ADT: 1,755
NYBERG ROAD
FairOver: I-5 (HWY 001)
0.4 MI S OF TUALATIN RV, Washington, OR
Built 1975 Load: 30.8 t ADT: 28,394
STRINGTOWN ROAD
FairOver: GALES CREEK
001 MI S GALES CREEK ROAD, Washington, OR
Built 1958 Load: 31.8 t ADT: 491
Hwy 29
FairOver: Carpenter Creek
006 MI S FOREST GROVE SCL, Washington, OR
Built 1975 Load: 32.4 t ADT: 13,003
HWY 140
FairOver: MCFEE CREEK
090 MI N NEWBERG, Washington, OR
Built 1959 Load: 32.7 t ADT: 4,209
NW 185TH Ave
FairOver: Hwy 47 US 26
10.2 MI W OF PORTLAND CC, Washington, OR
Built 1972 Load: 32.7 t ADT: 34,707
LAFOLLETT RD
FairOver: TUALATIN RIVER OVERFLOW
.175 W. GOLF COURSE ROAD, Washington, OR
Built 2003 Load: 32.7 t ADT: 850
ROY ROGERS RD
FairOver: TUALATIN RIVER
006 MI N SCHOLLS-SHERWOOD, Washington, OR
Built 1971 Load: 32.7 t ADT: 6,446
185TH & BASELINE
FairOver: WILLOW CREEK EB
AT BASELINE ROAD, Washington, OR
Built 1988 Load: 32.7 t ADT: 21,247
Meridian Rd
FairOver: Hwy 064
1.9 MI S OF STAFFORD RD, Washington, OR
Built 1969 Load: 33.0 t ADT: 5,133
Hwy 29
FairOver: Creek
0.6 M IN GASTON PO, Washington, OR
Built 1967 Load: 33.4 t ADT: 9,084
FERN FLAT ROAD
FairOver: EAST FORK DAIRY CREEK
009 MI N GREENER ROAD, Washington, OR
Built 1998 Load: 33.4 t ADT: 43
NW AMBERWOOD DRIVE
FairOver: ROCK CR
.4 Mi E Cornelius Pass, Washington, OR
Built 1998 Load: 33.6 t ADT: 2,833
MT RICHMOND RD
FairOver: TUALATIN RIVER
003 MI N COUNTY LINE, Washington, OR
Built 1972 Load: 33.6 t ADT: 305
GREENBURG ROAD
FairOver: HWY 144
0.7 N TIGARD CC, Washington, OR
Built 1973 Load: 33.7 t ADT: 22,802
Hwy 29
FairOver: Creek
1.0 MI N GASTON PO, Washington, OR
Built 1967 Load: 34.0 t ADT: 9,084
Hwy 29
FairOver: Creek
0.3 MI N GASTON PO, Washington, OR
Built 1967 Load: 34.0 t ADT: 9,917
FERN FLAT ROAD
FairOver: PANTHER CREEK
010 MI N GREENER ROAD, Washington, OR
Built 2000 Load: 34.3 t ADT: 13
PADGETT ROAD
FairOver: MCKAY CREEK
008 W CONNELL ROAD, Washington, OR
Built 1971 Load: 34.5 t ADT: 765
CEDAR HILLS BLVD
FairOver: BEAVERTON CREEK
0034 N OF TV HWY, Washington, OR
Built 1959 Load: 34.5 t ADT: 13,600
SW MURRAY BLVD
FairOver: SUMMER CREEK
.25 MI S OF SCHOLLS FERY, Washington, OR
Built 2007 Load: 34.7 t ADT: 3,373
US 26 (HWY 047) EB
FairOver: PNWR & VADIS
17.0 MI W PORTLAND SWCL, Washington, OR
Built 1971 Load: 35.0 t ADT: 11,519
Hwy 064AA
FairOver: Hwy 001
AT I-5 INTERCHANGE, Washington, OR
Built 1970 Load: 35.0 t ADT: 17,493
CORNELIUS PASS RD
FairOver: ROCK CREEK
003 MI N R/R UNDERPASS, Washington, OR
Built 2012 Load: 36.3 t ADT: 25,168
CEDAR CANYON ROAD
FairOver: WEST FORK DAIRY CREEK
0072 W HWY 47, Washington, OR
Built 1971 Load: 36.3 t ADT: 1,895
197TH AVE
FairOver: BEAVERTON CREEK
001 MI S BASELINE RD, Washington, OR
Built 1971 Load: 36.3 t ADT: 7,559
Helevetia Rd
FairOver: Hwy 47 US 26
13.4 MI W OF PORTLAND CC, Washington, OR
Built 1985 Load: 36.9 t ADT: 15,110
US 26 (Hwy 047)
FairOver: Light Rail Transit
.3 M W OF HWY 144, Washington, OR
Built 1996 Load: 37.2 t ADT: 115,947
BASELINE RD
FairOver: BEAVERTON CREEK
0065 MI W 185TH AVE, Washington, OR
Built 2002 Load: 37.2 t ADT: 21,956
RODERICK ROAD
FairOver: GALES CREEK
001 MI W GALES CREEK ROAD, Washington, OR
Built 1972 Load: 37.2 t ADT: 184
US 26 (Hwy 047) EB
FairOver: East Fork Dairy Creek
20.0 MI W OF PORTLAND CC, Washington, OR
Built 1971 Load: 37.3 t ADT: 11,519
NORWOOD ROAD
FairOver: PACIFIC HWY 1 (I-5)
2.4 MI S OF TUALATIN R., Washington, OR
Built 1969 Load: 37.3 t ADT: 1,618
HORNECKER ROAD
FairOver: MCKAY CREEK
005 E PADGETT ROAD, Washington, OR
Built 1978 Load: 38.1 t ADT: 2,432
SAGERT ROAD
FairOver: HWY 1 I-5
0.9 MI S OF TUALATIN R., Washington, OR
Built 1969 Load: 38.6 t ADT: 5,452
SW SPRING HILL RD
FairOver: TUALATIN RIVER OVERFLOW
002 MI S R/R X-ING, Washington, OR
Built 2017 Load: 38.6 t ADT: 1,098
WEST UNION ROAD
FairOver: ROCK CREEK
0041 MI W 185TH AVENUE, Washington, OR
Built 1978 Load: 39.0 t ADT: 7,789
US 26 (Hwy 047) EB
FairOver: Bledsoe Creek
20.0 MI W OF PORTLAND CC, Washington, OR
Built 1971 Load: 39.9 t ADT: 11,519
GOLF COURSE ROAD
FairOver: TUALATIN RIVER OVERFLOW
010 MI S HWY 8, Washington, OR
Built 1997 Load: 39.9 t ADT: 3,824
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.