Worst Infrastructure: Wisconsin — 2026 Rankings

Out of 863 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	863
Highest risk	71%
Median risk	41%
Average risk	41%
State	Wisconsin

Top 100 Highest Risk ZIP Codes

Rank	ZIP Code	City	State	Pipe Failure Risk	Risk Level	Safety Score
1	53571	Morrisonville	WI	71%	Very High	66/100
2	53206	Milwaukee	WI	68%	Very High	80/100
3	53208	Milwaukee	WI	68%	Very High	75/100
4	53210	Milwaukee	WI	68%	Very High	80/100
5	53215	Milwaukee	WI	67%	Very High	75/100
6	53204	Milwaukee	WI	66%	Very High	80/100
7	53211	Milwaukee	WI	64%	Very High	75/100
8	53212	Milwaukee	WI	63%	Very High	80/100
9	53213	Milwaukee	WI	63%	Very High	70/100
10	53216	Milwaukee	WI	63%	Very High	70/100
11	53214	Milwaukee	WI	61%	Very High	80/100
12	53219	Milwaukee	WI	61%	Very High	80/100
13	54417	Brokaw	WI	61%	Very High	40/100
14	53209	Milwaukee	WI	60%	High	65/100
15	54127	Green Valley	WI	60%	High	63/100
16	54160	Potter	WI	59%	High	63/100
17	53039	Juneau	WI	58%	High	24/100
18	53094	Watertown	WI	58%	High	28/100
19	53187	Waukesha	WI	58%	High	36/100
20	53217	Milwaukee	WI	58%	High	65/100
21	53218	Milwaukee	WI	58%	High	65/100
22	54880	Superior	WI	58%	High	61/100
23	53110	Cudahy	WI	57%	High	73/100
24	53143	Kenosha	WI	57%	High	69/100
25	53222	Milwaukee	WI	57%	High	75/100
26	53233	Milwaukee	WI	57%	High	80/100
27	53706	Madison	WI	57%	High	59/100
28	53919	Brandon	WI	57%	High	60/100
29	54152	Nichols	WI	57%	High	83/100
30	53226	Milwaukee	WI	56%	High	75/100
31	53538	Fort Atkinson	WI	56%	High	34/100
32	53939	Kingston	WI	56%	High	40/100
33	54211	Ephraim	WI	56%	High	40/100
34	53146	New Berlin	WI	55%	High	68/100
35	53186	Waukesha	WI	55%	High	41/100
36	53195	Zenda	WI	55%	High	40/100
37	53225	Milwaukee	WI	55%	High	75/100
38	53227	Milwaukee	WI	55%	High	75/100
39	53586	Shullsburg	WI	55%	High	67/100
40	53029	Hartland	WI	54%	High	48/100
41	53205	Milwaukee	WI	54%	High	80/100
42	53925	Columbus	WI	54%	High	61/100
43	54227	Maribel	WI	54%	High	79/100
44	54245	Valders	WI	54%	High	77/100
45	54475	Rudolph	WI	54%	High	40/100
46	54643	Millston	WI	54%	High	53/100
47	54806	Ashland	WI	54%	High	45/100
48	53032	Horicon	WI	53%	High	65/100
49	53050	Mayville	WI	53%	High	53/100
50	53105	Burlington	WI	53%	High	49/100
51	53176	Springfield	WI	53%	High	53/100
52	53203	Milwaukee	WI	53%	High	80/100
53	53207	Milwaukee	WI	53%	High	80/100
54	53565	Mineral Point	WI	53%	High	43/100
55	53956	Randolph	WI	53%	High	40/100
56	54449	Marshfield	WI	53%	High	44/100
57	54645	Mount Sterling	WI	53%	High	28/100
58	54805	Almena	WI	53%	High	77/100
59	54911	Appleton	WI	53%	High	67/100
60	54928	Caroline	WI	53%	High	40/100
61	53098	Watertown	WI	52%	High	28/100
62	53140	Kenosha	WI	52%	High	69/100
63	53223	Milwaukee	WI	52%	High	70/100
64	53404	Racine	WI	52%	High	75/100
65	53405	Racine	WI	52%	High	75/100
66	53803	Benton	WI	52%	High	64/100
67	53916	Beaver Dam	WI	52%	High	54/100
68	53946	Markesan	WI	52%	High	65/100
69	54241	Two Rivers	WI	52%	High	52/100
70	54409	Antigo	WI	52%	High	56/100
71	54437	Greenwood	WI	52%	High	83/100
72	54464	Phlox	WI	52%	High	40/100
73	54625	Dodge	WI	52%	High	55/100
74	54721	Arkansaw	WI	52%	High	40/100
75	54771	Thorp	WI	52%	High	56/100
76	53006	Brownsville	WI	51%	High	65/100
77	53188	Waukesha	WI	51%	High	41/100
78	53202	Milwaukee	WI	51%	High	80/100
79	53235	Saint Francis	WI	51%	High	40/100
80	53403	Racine	WI	51%	High	80/100
81	53501	Afton	WI	51%	High	53/100
82	53549	Jefferson	WI	51%	High	40/100
83	53581	Richland Center	WI	51%	High	46/100
84	53726	Madison	WI	51%	High	59/100
85	53942	Lime Ridge	WI	51%	High	40/100
86	53943	Loganville	WI	51%	High	83/100
87	53965	Wisconsin Dells	WI	51%	High	77/100
88	53969	Wyocena	WI	51%	High	83/100
89	54006	Cushing	WI	51%	High	53/100
90	54213	Forestville	WI	51%	High	53/100
91	54450	Mattoon	WI	51%	High	65/100
92	54481	Stevens Point	WI	51%	High	46/100
93	54498	Withee	WI	51%	High	83/100
94	54769	Stockholm	WI	51%	High	45/100
95	54841	Haugen	WI	51%	High	82/100
96	54922	Bear Creek	WI	51%	High	64/100
97	54950	Marion	WI	51%	High	70/100
98	53079	Saint Cloud	WI	50%	High	40/100
99	53093	Waldo	WI	50%	High	83/100
100	53183	Wales	WI	50%	High	68/100

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: 2026-07-19.

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.