Least Reliable Water Systems in Illinois — 2026

Out of 1,583 ZIP codes with data in Illinois, these are the lowest-ranked areas for reliability score. See also: National Least Reliable Water Systems in America | All Illinois Rankings

Statistic	Value
ZIP codes ranked	1,583
Lowest value	10/100
Median value	65/100
State	Illinois

100 Lowest-Ranked ZIP Codes

Rank	ZIP Code	City	State	Reliability Score	Safety Score
1	61771	Secor	IL	10/100	33/100
2	61354	Peru	IL	15/100	57/100
3	62288	Steeleville	IL	15/100	63/100
4	62649	Hettick	IL	20/100	63/100
5	61350	Ottawa	IL	21/100	66/100
6	60512	Bristol	IL	22/100	61/100
7	60932	East Lynn	IL	22/100	61/100
8	60974	Woodland	IL	22/100	56/100
9	61089	Winslow	IL	22/100	41/100
10	61344	Mineral	IL	22/100	66/100
11	61345	Neponset	IL	22/100	61/100
12	61439	Henderson	IL	22/100	66/100
13	61449	La Fayette	IL	22/100	61/100
14	61532	Forest City	IL	22/100	66/100
15	62349	Loraine	IL	22/100	29/100
16	62886	Sims	IL	22/100	67/100
17	62887	Springerton	IL	22/100	67/100
18	60912	Beaverville	IL	24/100	36/100
19	61413	Alpha	IL	24/100	51/100
20	61957	Windsor	IL	24/100	68/100
21	60416	Coal City	IL	25/100	47/100
22	60919	Cabery	IL	25/100	42/100
23	61282	Silvis	IL	25/100	47/100
24	61726	Chenoa	IL	25/100	41/100
25	62531	Edinburg	IL	25/100	62/100
26	62670	New Berlin	IL	25/100	62/100
27	62674	Palmyra	IL	25/100	50/100
28	60041	Ingleside	IL	27/100	66/100
29	60150	Malta	IL	27/100	50/100
30	60407	Braceville	IL	27/100	66/100
31	60954	Momence	IL	27/100	58/100
32	61241	Colona	IL	27/100	56/100
33	61242	Cordova	IL	27/100	53/100
34	61250	Erie	IL	27/100	61/100
35	61273	Orion	IL	27/100	66/100
36	61323	Dover	IL	27/100	61/100
37	61341	Marseilles	IL	27/100	53/100
38	61374	Van Orin	IL	27/100	61/100
39	61465	New Windsor	IL	27/100	57/100
40	61488	Wataga	IL	27/100	61/100
41	61534	Green Valley	IL	27/100	61/100
42	61811	Alvin	IL	27/100	58/100
43	62015	Butler	IL	27/100	78/100
44	62033	Gillespie	IL	27/100	79/100
45	62077	Panama	IL	27/100	66/100
46	62248	Hecker	IL	27/100	78/100
47	62249	Highland	IL	27/100	79/100
48	62275	Pocahontas	IL	27/100	78/100
49	62413	Annapolis	IL	27/100	67/100
50	62439	Lawrenceville	IL	27/100	49/100
51	62568	Taylorville	IL	27/100	79/100
52	62812	Benton	IL	27/100	54/100
53	61919	Camargo	IL	28/100	49/100
54	61036	Galena	IL	29/100	60/100
55	60002	Antioch	IL	30/100	54/100
56	60155	Broadview	IL	30/100	66/100
57	60431	Joliet	IL	30/100	49/100
58	60432	Joliet	IL	30/100	44/100
59	60433	Joliet	IL	30/100	44/100
60	60434	Joliet	IL	30/100	59/100
61	60435	Joliet	IL	30/100	49/100
62	60436	Joliet	IL	30/100	49/100
63	60472	Robbins	IL	30/100	64/100
64	61933	Kansas	IL	30/100	40/100
65	62019	Donnellson	IL	30/100	61/100
66	62215	Albers	IL	30/100	62/100
67	62259	Menard	IL	30/100	61/100
68	62417	Bridgeport	IL	30/100	60/100
69	62460	Saint Francisville	IL	30/100	60/100
70	62543	Latham	IL	30/100	54/100
71	62650	Jacksonville	IL	30/100	45/100
72	62651	Jacksonville	IL	30/100	47/100
73	62667	Modesto	IL	30/100	56/100
74	62906	Anna	IL	30/100	72/100
75	62983	Royalton	IL	30/100	72/100
76	62216	Aviston	IL	31/100	35/100
77	62414	Beecher City	IL	31/100	53/100
78	62938	Golconda	IL	31/100	57/100
79	60151	Maple Park	IL	32/100	58/100
80	61061	Oregon	IL	32/100	56/100
81	61334	Lostant	IL	32/100	83/100
82	61338	Manlius	IL	32/100	61/100
83	61356	Princeton	IL	32/100	36/100
84	61375	Varna	IL	32/100	66/100
85	61852	Longview	IL	32/100	61/100
86	62023	Eagarville	IL	32/100	67/100
87	62032	Fillmore	IL	32/100	71/100
88	62081	Rockbridge	IL	32/100	66/100
89	62238	Cutler	IL	32/100	67/100
90	62355	Nebo	IL	32/100	63/100
91	62634	Elkhart	IL	32/100	57/100
92	62832	Du Quoin	IL	32/100	79/100
93	61752	Le Roy	IL	33/100	38/100
94	62263	Nashville	IL	33/100	76/100
95	61571	Washington	IL	34/100	60/100
96	61732	Danvers	IL	34/100	62/100
97	62220	Belleville	IL	34/100	76/100
98	62221	Belleville	IL	34/100	76/100
99	62222	Belleville	IL	34/100	81/100
100	62223	Belleville	IL	34/100	76/100

Methodology

Water system reliability scores (0-100) combine violation frequency, violation recency, resolution rate, and system size. Systems with repeated health-based violations and unresolved issues score lowest. The reliability score focuses specifically on the water utility performance, distinct from the broader Home Safety Score.

Data sources: EPA Safe Drinking Water Information System (SDWIS), FEMA National Flood Insurance Program, EPA radon zone maps, EIA electricity rates, and Consumer Confidence Reports. Last updated: 2026-04-13.

Frequently Asked Questions

What does a low water reliability score mean?

A low reliability score (below 50) indicates a water system with frequent violations, poor resolution rates, or recurring compliance issues. These systems may have aging infrastructure, inadequate treatment, or management challenges.

How is reliability different from safety score?

The reliability score focuses specifically on the water utility performance (violations, resolution, compliance). The Home Safety Score is broader, also including lead risk, radon, and flood data. A ZIP code can have a reliable water system but still have high radon or flood risk.