County profile · official public datasets

Door County, WI

32 public highway bridges tracked in the FHWA National Bridge Inventory: 46.9% rated Good, 50% Fair, 3.1% Poor.

32
Public bridges
46.9%
Good condition
3.1%
Poor condition

The verdict

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

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

Top 13%
lowest Poor share in state
3.1%
Poor-condition share
32
public highway bridges
1985
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.

Door County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Door County ranks #9 of 72 Wisconsin counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 3.1%). Door County, Wisconsin contains 32 public highway bridges. Roughly 46.9% are rated “Good,” 50% “Fair,” and 3.1% “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

32

Public highway bridges in Door County

Good condition

46.9%

15 of 32 rated 7-9

Fair condition

50%

16 of 32 rated 5-6

Poor condition

3.1%

1 of 32 rated 4 or below

In-state Poor-share rank

#9 of 72

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

Condition distribution

Share of 32 NBI-tracked bridges by lowest applicable component rating.

Good
46.9% (15)
Fair
50% (16)
Poor
3.1% (1)

Door County's Poor-condition bridges carry 235 vehicle crossings a day

That is 0.1% of the county's reported daily bridge traffic on 3.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 235 crossings a day against 4,505 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 32 of 32 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

18.8% of Door County's bridges have passed the 50-year mark

6 of the 32 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 46.9% 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 100% of the county's Poor-condition bridge traffic

CTH N over GREEN BAY TRIBUTARY, built 1965, carries 235 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 1-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 235 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Door County's bridges were built

32 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 2000s, when 11 of the county's bridges still in the inventory were built, which is 34.4% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year (1985) matches the Wisconsin average (1984).

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

How Door County compares with Wisconsin's closest counties by inventory size

The 5 Wisconsin counties nearest Door County in number of bridges, with their condition splits. Its 3.1% Poor share is the 3rd-lowest of these 6. Its average build year of 1985 against a peer-group mean of 1983 is in line with the group.

Showing the 5 closest of 71 Wisconsin counties eligible for comparison.

Bridge inventory size and condition shares for Door County and the 5 Wisconsin counties closest to it in inventory size
County Bridges Poor
Green Lake County 48 2.1%
Adams County 41 2.4%
Door County (this page) 32 3.1%
Vilas County 29 10.3%
Menominee County 25 8%
Florence County 20 5%

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 Door 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 Door County, both outside Wisconsin so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside WI (32 bridges here).

Similar average build year

Nearest mean year-built outside WI (1985 here).

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

All 32 Good 15 Fair 16 Poor 1

All bridges (32)

LRD TOWN RD

Fair

Over: WHITEFISH BAY CREEK

0.8M E JCT CTH T, Door, WI

Built 1955 Load: 24.3 t ADT: 293

STH 42 - STH 57

Fair

Over: STURGEON BAY

1.9M N JCT CTH S, Door, WI

Built 1978 Load: 27.5 t ADT: 12,500

STH 42 - STH 57

Fair

Over: STURGEON BAY

1.9M N JCT CTH S, Door, WI

Built 1978 Load: 29.2 t ADT: 12,500

STH 42 - STH 57

Fair

Over: LRD MEMORIAL DR

1.9M N JCT CTH S, Door, WI

Built 1978 Load: 29.2 t ADT: 12,500

STH 42 SB-STH 57 S

Fair

Over: LRD GREEN BAY RD

2.8M S JCT CTH TT, Door, WI

Built 1977 Load: 30.8 t ADT: 8,100

STH 42 NB-STH 57 N

Fair

Over: LRD GREEN BAY RD

0.1M N JCT CTH S, Door, WI

Built 1977 Load: 30.8 t ADT: 8,100

CTH J

Fair

Over: STONEY CREEK

0.9M W JCT CTH S, Door, WI

Built 1987 Load: 32.4 t ADT: 212

STH 57 NB

Fair

Over: FABRY CR

2.2 MI N OF CO LINE, Door, WI

Built 2008 Load: 32.4 t ADT: 10,800

LRD W CARNOT RD

Fair

Over: STONEY CREEK

0.5M W OF S CARNOT ROAD, Door, WI

Built 1987 Load: 37.3 t ADT: 85

CTH X

Fair

Over: AHNAPEE RIVER

0.8M E JCT CTH D, Door, WI

Built 1989 Load: 37.3 t ADT: 678

STH 42 - STH 57

Fair

Over: STURGEON BAY

1.9M N JCT CTH S, Door, WI

Built 1978 Load: 40.5 t ADT: 12,500

STH 42 - STH 57

Fair

Over: STURGEON BAY

1.9M N JCT CTH S, Door, WI

Built 1978 Load: 40.5 t ADT: 12,500

LRD MICHIGAN STREE

Fair

Over: STURGEON BAY

1.0M N JCT STH 42, Door, WI

Built 1930 Load: 42.1 t ADT: 5,400

LRD MICHIGAN STREE

Fair

Over: STURGEON BAY

1.0M N JCT STH 42, Door, WI

Built 1930 Load: 45.4 t ADT: 8,300

LRD MICHIGAN STREE

Fair

Over: STURGEON BAY

1.0M N JCT STH 42, Door, WI

Built 1930 Load: 45.4 t ADT: 8,300

CTH T

Fair

Over: SHIVERING SANDS CREEK

5.8M N JCT STH 42, Door, WI

Built 1985 Load: 47.0 t ADT: 433

LRD S CARNOT ROAD

Good

Over: STONEY CREEK

0.3M N JCT CTH J, Door, WI

Built 1986 Load: 24.3 t ADT: 174

LRD MAPLEWOOD ROAD

Good

Over: STONEY CREEK

0.2M E JCT CTH O, Door, WI

Built 1998 Load: 32.4 t ADT: 1

LRD ISLAND CIRCLE

Good

Over: UNKNOWN CREEK

0.1M N JCT HIGH CLIFF PK, Door, WI

Built 2006 Load: 32.4 t ADT: 100

LRD MAPLE/OREGON S

Good

Over: STURGEON BAY

1.0M N JCT STH 42, Door, WI

Built 2008 Load: 34.0 t ADT: 5,700

LRD MAPLE/OREGON S

Good

Over: STURGEON BAY

1.0M N JCT STH 42, Door, WI

Built 2008 Load: 34.0 t ADT: 5,700

LRD MAPLE/OREGON S

Good

Over: STURGEON BAY

1.0M N JCT STH 42, Door, WI

Built 2008 Load: 34.0 t ADT: 5,700

STH 57 SB

Good

Over: AHNAPEE R

0.9 MI E OF SCHOOL LANE, Door, WI

Built 2005 Load: 35.6 t ADT: 5,750

STH 42

Good

Over: COFFRIN CREEK

0.97 MI N OF CTH X LT, Door, WI

Built 2015 Load: 38.2 t ADT: 1,500

STH 57 NB

Good

Over: AHNAPEE R

0.9 MI E OF SCHOOL RD, Door, WI

Built 2005 Load: 38.9 t ADT: 5,750

STH 57 NB

Good

Over: RENARD CR

0.80 MI N OF CTH D, Door, WI

Built 2008 Load: 38.9 t ADT: 5,400

STH 57 SB

Good

Over: RENARD CR

0.8 MI N OF CTH D, Door, WI

Built 2008 Load: 38.9 t ADT: 5,400

LRD MAPLE/OREGON S

Good

Over: LAND

1.0M N JCT STH 42, Door, WI

Built 2008 Load: 40.5 t ADT: 6,800

LRD MAPLE/OREGON S

Good

Over: LAND

1.0M N JCT STH 42, Door, WI

Built 2008 Load: 40.5 t ADT: 6,800

STH 57

Good

Over: BAILEYS HARBOR MARSH

2.70 MI N OF CTH Q, Door, WI

Built 2017 Load: 44.4 t ADT: 4,500

LRD MICHIGAN STREE

Good

Over: STURGEON BAY

1.0M N JCT STH 42, Door, WI

Built 1930 Load: 45.4 t ADT: 8,300

CTH N

Poor

Over: GREEN BAY TRIBUTARY

0.8M N JCT STH 57, Door, WI

Built 1965 Load: 19.4 t ADT: 235

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

Related

Browse all → | Rankings →
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.