County profile · official public datasets

Jackson County, OR

401 public highway bridges tracked in the FHWA National Bridge Inventory: 34.2% rated Good, 64.3% Fair, 1.5% Poor.

401
Public bridges: 34.2%
Good condition: 1.5%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Jackson County posts a top-quartile lowest Poor-condition share among rated counties in the state across mid-size county bridge inventory.

Top 19%
lowest Poor share in state: 1.5%
Poor-condition share: 401
public highway bridges: 1976
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.

Jackson County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Jackson County ranks #7 of 36 Oregon counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 1.5%). Jackson County, Oregon contains 401 public highway bridges. Roughly 34.2% are rated “Good,” 64.3% “Fair,” and 1.5% “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.

Total bridges

401

Public highway bridges in Jackson County

Good condition

34.2%

137 of 401 rated 7-9

Fair condition

64.3%

258 of 401 rated 5-6

Poor condition

1.5%

6 of 401 rated 4 or below

In-state Poor-share rank

#7 of 36

Among Oregon counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 401 NBI-tracked bridges by lowest applicable component rating.

Good

34.2% (137)

Fair

64.3% (258)

Poor

1.5% (6)

Jackson County's Poor-condition bridges carry 31,147 vehicle crossings a day

That is 1.5% of the county's reported daily bridge traffic on 1.5% of its bridges: Poor-condition structures carry the same share of traffic than their share of the inventory. Each Poor bridge averages 5,191 crossings a day against 2,648 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 401 of 401 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

55.6% of Jackson County's bridges have passed the 50-year mark

223 of the 401 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 34.2% 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 58.8% of the county's Poor-condition bridge traffic

I-5 (HWY 001) NB over OR 99 (HWY 060), built 1961, carries 18,321 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 6-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 31,147 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1910s

6
1920s

7
1930s

12
1940s

4
1950s

62
1960s

114
1970s

43
1980s

25
1990s

23
2000s

77
2010s

23
2020s

5

What this shows Construction peaked in the 1960s, when 114 of the county's bridges still in the inventory were built, which is 28.4% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1976) matches the Oregon average (1975).

How Jackson County compares with Oregon's closest counties by inventory size

The 5 Oregon counties nearest Jackson County in number of bridges, with their condition splits. Its 1.5% Poor share is the 1st-lowest of these 6. Its average build year of 1976 against a peer-group mean of 1974 is in line with the group.

Showing the 5 closest of 35 Oregon counties eligible for comparison.

Bridge inventory size and condition shares for Jackson County and the 5 Oregon counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Multnomah County	473	11.8%	85.2%	3%	1967
Jackson County (this page)	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	326	35.6%	62%	2.5%	1983
Umatilla County	321	31.5%	64.5%	4%	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 Jackson 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 Jackson County, both outside Oregon so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside OR (401 bridges here).

San Luis Obispo County, CA · 401 bridges
Vernon County, MO · 401 bridges
Randolph County, NC · 401 bridges
Marshall County, KS · 402 bridges

Similar average build year

Nearest mean year-built outside OR (1976 here).

Marion County, IN · avg 1976 · 958 bridges
Mohave County, AZ · avg 1976 · 641 bridges
Comanche County, OK · avg 1976 · 593 bridges
Prince George's County, MD · avg 1976 · 576 bridges

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 401 Good 137 Fair 258 Poor 6

Fair-condition bridges (258)

Sort:

Jackson County Bridge Snapshot

Condition distribution

Jackson County's Poor-condition bridges carry 31,147 vehicle crossings a day

55.6% of Jackson County's bridges have passed the 50-year mark

One structure carries 58.8% of the county's Poor-condition bridge traffic

How Jackson County compares with Oregon's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Fair-condition bridges (258)

DEER CK RIDGE ROAD

NO DATA ENTERED

NO DATA ENTERED

NO DATA ENTERED

Lampman Rd. (#807)

OR 62 (HWY 022)

OR 99 (HWY 271)

OR 234 (HWY 271)

AGATE RD

OR 62 (HWY 022)

OR 99 (HWY 486)

OR 62 (HWY 022)

OR 230 (HWY 233)

I-5 (HWY 001)

COUNTY ROAD NO 971

I-5 (HWY 001)

I-5 (HWY 001) NB

OR 99 (HWY 060)

TABLE ROCK RD

I-5 (HWY 001) SB

OR 62 (HWY 022)

THOMPSON CREEK RD

40 S 04 E 03.00:

CENTRAL PT RD CON2

COUNTY RD 790

OR 273 (HWY 273)

E PINE ST (WB)

OR 99 (HWY 060)

OR 99 (HWY 060)

OR 99 (HWY 060)

CO RD (MNT AVE)

COUNTY RD 807

COUNTY RD 751

OR 273 (HWY 273)

E PINE ST (EB)

TILLER-TRAIL HWY

BARNETT RD

UPTON ROAD

COUNTY RD 651

COUNTY RD 682

COUNTY RD 797

OR 238 (HWY 272)

TAYLOR ROAD

I-5 (HWY 001)

OR 140 (HWY 270)

AGATE RD

34 S 03 W 24.00:

OR 99 (HWY 063)

COUNTY ROAD NO 810

I-5 (HWY 001) SB

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