County profile · official public datasets

Waukesha County, WI

369 public highway bridges tracked in the FHWA National Bridge Inventory: 53.1% rated Good, 40.4% Fair, 6.5% Poor.

369
Public bridges: 53.1%
Good condition: 6.5%
Poor condition

The verdict

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

Waukesha County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

42nd
of 72 on Poor share: 6.5%
Poor-condition share: 369
public highway bridges: 1984
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.

Waukesha County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Waukesha County ranks #42 of 72 Wisconsin counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6.5%). Waukesha County, Wisconsin contains 369 public highway bridges. Roughly 53.1% are rated “Good,” 40.4% “Fair,” and 6.5% “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

369

Public highway bridges in Waukesha County

Good condition

53.1%

196 of 369 rated 7-9

Fair condition

40.4%

149 of 369 rated 5-6

Poor condition

6.5%

24 of 369 rated 4 or below

In-state Poor-share rank

#42 of 72

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

Condition distribution

Share of 369 NBI-tracked bridges by lowest applicable component rating.

Good

53.1% (196)

Fair

40.4% (149)

Poor

6.5% (24)

Waukesha County's Poor-condition bridges carry 70,131 vehicle crossings a day

That is 1.5% of the county's reported daily bridge traffic on 6.3% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 3,049 crossings a day against 9,833 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 368 of 369 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

38.8% of Waukesha County's bridges have passed the 50-year mark

143 of the 369 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 53.1% 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 25.2% of the county's Poor-condition bridge traffic

CTH F NB over IH 94, built 1977, carries 17,650 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 24-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 70,131 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

1
1910s

5
1920s

6
1930s

3
1940s

5
1950s

16
1960s

77
1970s

43
1980s

46
1990s

44
2000s

58
2010s

56
2020s

9

What this shows Construction peaked in the 1960s, when 77 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 55 to 64 years old in the 2024 inventory. Its average build year (1984) matches the Wisconsin average (1984).

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

The 5 Wisconsin counties nearest Waukesha County in number of bridges, with their condition splits. Its 6.5% Poor share is the 4th-lowest of these 6. Its average build year of 1984 against a peer-group mean of 1982 is in line with the group.

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

Bridge inventory size and condition shares for Waukesha County and the 5 Wisconsin counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Grant County	383	66.1%	29.5%	4.4%	1984
Monroe County	374	50.5%	46%	3.5%	1981
Waukesha County (this page)	369	53.1%	40.4%	6.5%	1984
Chippewa County	359	34.8%	56%	9.2%	1985
Vernon County	333	44.1%	48.3%	7.5%	1983
Barron County	319	48.6%	45.8%	5.6%	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 Waukesha 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 Waukesha County, both outside Wisconsin so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside WI (369 bridges here).

Saline County, KS · 369 bridges
Suffolk County, NY · 369 bridges
Cass County, ND · 369 bridges
Collier County, FL · 370 bridges

Similar average build year

Nearest mean year-built outside WI (1984 here).

Hennepin County, MN · avg 1984 · 936 bridges
Duval County, FL · avg 1984 · 831 bridges
El Paso County, CO · avg 1984 · 686 bridges
Bell County, TX · avg 1984 · 660 bridges

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

All 369 Good 196 Fair 149 Poor 24

Good-condition bridges (196)

Sort:

Waukesha County Bridge Snapshot

Condition distribution

Waukesha County's Poor-condition bridges carry 70,131 vehicle crossings a day

38.8% of Waukesha County's bridges have passed the 50-year mark

One structure carries 25.2% of the county's Poor-condition bridge traffic

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

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Good-condition bridges (196)

LRD OAKWOOD AVE

USH 18 WB

USH 18 EB

CTH Q / COUNTY LIN

IH 43 SB

STH 83 SB

USH 18 WB

USH 18 EB

STH 83 SB

STH 59 EB

STH 59 WB

LRD SUNNY SLOPE RD

STH 83 NB

STH 190 WB

STH 190 EB

CTH BB (GOLDEN LAK

CTH X (GENESEE RO

CTH K (LISBON RD)

STH 59 WB

STH 16 WB

STH 16 EB

LRD CTH Y (BARKER

STH 67 NB

LRD PILGRIM ROAD S

LRD MADISON ST.

CTH M (NORTH AVE)

LRD CALHOUN ROAD

LRD SUNNYSLOPE ROA

USH 18

LRD MILL STREET

LRD WALL STREET

CTH K

CTH F SB (REDFORD

CTH D (SUNSET DR)

LRD GLACIER RD

STH 16 EB

STH 164 NB

STH 164 NB

STH 164 SB

CTH ES (NATIONAL A

LRD PILGRIM RD NB

LRD DUPLAINVILLE R

IH 43 NB

IH 43 SB

CTH Y (LANNON RD)

STH 83 NB

LRD ELM GROVE ROAD

LRD WOODS RD

STH 67 SB

LRD DAVIDSON ROAD

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