Worst Infrastructure: Wisconsin — 2026 Rankings

Out of 840 ZIP codes with infrastructure data in Wisconsin, these areas face the highest estimated risk of water pipe failure based on infrastructure age, funding gaps, and violation history.

Statistic	Value
ZIP codes ranked	840
Highest risk	59%
Median risk	38%
Average risk	39%
State	Wisconsin

Top 100 Highest Risk ZIP Codes

Rank	ZIP Code	City	State	Pipe Failure Risk	Risk Level	Safety Score
1	54880	Superior	WI	59%	High	61/100
2	53039	Juneau	WI	58%	High	24/100
3	53094	Watertown	WI	57%	High	28/100
4	53143	Kenosha	WI	57%	High	69/100
5	53706	Madison	WI	57%	High	59/100
6	53571	Morrisonville	WI	56%	High	66/100
7	54901	Oshkosh	WI	56%	High	55/100
8	53186	Waukesha	WI	55%	High	41/100
9	53195	Zenda	WI	54%	High	40/100
10	54806	Ashland	WI	54%	High	45/100
11	54902	Oshkosh	WI	54%	High	50/100
12	53176	Springfield	WI	53%	High	53/100
13	53206	Milwaukee	WI	53%	High	80/100
14	53208	Milwaukee	WI	53%	High	75/100
15	53210	Milwaukee	WI	53%	High	80/100
16	53215	Milwaukee	WI	53%	High	75/100
17	53565	Mineral Point	WI	53%	High	43/100
18	53577	Plain	WI	53%	High	77/100
19	53956	Randolph	WI	53%	High	40/100
20	54645	Mount Sterling	WI	53%	High	28/100
21	53050	Mayville	WI	52%	High	53/100
22	53098	Watertown	WI	52%	High	28/100
23	53140	Kenosha	WI	52%	High	69/100
24	53204	Milwaukee	WI	52%	High	80/100
25	53404	Racine	WI	52%	High	75/100
26	53405	Racine	WI	52%	High	75/100
27	53522	Browntown	WI	52%	High	65/100
28	53969	Wyocena	WI	52%	High	83/100
29	54241	Two Rivers	WI	52%	High	52/100
30	54409	Antigo	WI	52%	High	56/100
31	54449	Marshfield	WI	52%	High	44/100
32	54625	Dodge	WI	52%	High	55/100
33	54771	Thorp	WI	52%	High	56/100
34	54980	Waukau	WI	52%	High	53/100
35	53188	Waukesha	WI	51%	High	41/100
36	53207	Milwaukee	WI	51%	High	80/100
37	53403	Racine	WI	51%	High	80/100
38	53549	Jefferson	WI	51%	High	40/100
39	53581	Richland Center	WI	51%	High	46/100
40	53726	Madison	WI	51%	High	59/100
41	53965	Wisconsin Dells	WI	51%	High	77/100
42	54450	Mattoon	WI	51%	High	65/100
43	54481	Stevens Point	WI	51%	High	46/100
44	54841	Haugen	WI	51%	High	82/100
45	53081	Sheboygan	WI	50%	High	74/100
46	53211	Milwaukee	WI	50%	High	75/100
47	53212	Milwaukee	WI	50%	High	80/100
48	53213	Milwaukee	WI	50%	High	70/100
49	53216	Milwaukee	WI	50%	High	70/100
50	53505	Avalon	WI	50%	High	40/100
51	53806	Cassville	WI	50%	High	64/100
52	53189	Waukesha	WI	49%	High	46/100
53	53714	Madison	WI	49%	High	64/100
54	54215	Kellnersville	WI	49%	High	48/100
55	54301	Green Bay	WI	49%	High	71/100
56	54403	Wausau	WI	49%	High	67/100
57	54495	Wisconsin Rapids	WI	49%	High	57/100
58	53168	Salem	WI	48%	High	63/100
59	53172	South Milwaukee	WI	48%	High	72/100
60	53209	Milwaukee	WI	48%	High	65/100
61	53214	Milwaukee	WI	48%	High	80/100
62	53219	Milwaukee	WI	48%	High	80/100
63	53402	Racine	WI	48%	High	80/100
64	53501	Afton	WI	48%	High	53/100
65	53541	Gratiot	WI	48%	High	65/100
66	53555	Lodi	WI	48%	High	43/100
67	53705	Madison	WI	48%	High	64/100
68	53716	Madison	WI	48%	High	59/100
69	53935	Friesland	WI	48%	High	82/100
70	53963	Waupun	WI	48%	High	61/100
71	54127	Green Valley	WI	48%	High	63/100
72	54303	Green Bay	WI	48%	High	71/100
73	54417	Brokaw	WI	48%	High	40/100
74	54530	Hawkins	WI	48%	High	77/100
75	54541	Laona	WI	48%	High	76/100
76	54638	Kendall	WI	48%	High	72/100
77	54741	Fairchild	WI	48%	High	76/100
78	54911	Appleton	WI	48%	High	67/100
79	54935	Fond Du Lac	WI	48%	High	42/100
80	53073	Plymouth	WI	47%	High	76/100
81	53121	Elkhorn	WI	47%	High	41/100
82	53127	Genesee Depot	WI	47%	High	40/100
83	53192	Wilmot	WI	47%	High	53/100
84	53538	Fort Atkinson	WI	47%	High	34/100
85	53545	Janesville	WI	47%	High	47/100
86	53569	Montfort	WI	47%	High	64/100
87	53582	Ridgeway	WI	47%	High	56/100
88	53599	Woodford	WI	47%	High	40/100
89	53704	Madison	WI	47%	High	59/100
90	53810	Glen Haven	WI	47%	High	53/100
91	53818	Platteville	WI	47%	High	54/100
92	53942	Lime Ridge	WI	47%	High	40/100
93	54125	Goodman	WI	47%	High	76/100
94	54160	Potter	WI	47%	High	63/100
95	54201	Algoma	WI	47%	High	75/100
96	54207	Collins	WI	47%	High	53/100
97	54458	Nelsonville	WI	47%	High	40/100
98	54464	Phlox	WI	47%	High	40/100
99	54536	Iron Belt	WI	47%	High	82/100
100	54550	Montreal	WI	47%	High	82/100

Methodology

Infrastructure risk rankings combine four data sources, each weighted equally (25%): (1) EPA Drinking Water Infrastructure Needs Survey (DWINS 2023) — state-level 20-year funding gap per capita for pipe replacement, treatment, and storage; (2) Census ACS housing vintage — percentage of homes built before 1980, when lead solder and galvanized pipes were common; (3) EPA SDWIS violation and enforcement data — system-level compliance history; (4) Lead and Copper Rule indicators — service line material inventories and 90th percentile lead testing results. The combined score is normalized to a 0-100% probability scale.

Data sources: EPA DWINS 2023, Census ACS, EPA SDWIS, Lead and Copper Rule data. Last updated: 2026-06-04.

Frequently Asked Questions

What does pipe failure probability mean?

Pipe failure probability estimates the likelihood of water main breaks, lead contamination from corroded pipes, or service disruptions based on infrastructure age, state funding gaps, violation history, and lead indicators. It is not a prediction of imminent failure, but a risk assessment based on known factors.

How is infrastructure risk calculated?

The risk score combines four equally weighted factors: state-level infrastructure funding gap per capita (from EPA DWINS 2023), housing vintage (Census ACS pre-1980 housing percentage), water system violation and enforcement history (EPA SDWIS), and lead exposure indicators (service line probability and testing results).

What can homeowners do about aging infrastructure?

Test your tap water annually, especially for lead. Check if your home has a lead service line through your water utility. Consider a whole-house water filter (NSF/ANSI 53 certified). Review your water system Consumer Confidence Report for violation history.

Does high risk mean my water is unsafe right now?

Not necessarily. Infrastructure risk indicates long-term vulnerability, not current contamination. However, areas with aging pipes and high violation counts have a statistically higher chance of water quality issues. Regular testing is the best way to verify your water safety.