Least Reliable Water Systems in Indiana — 2026

Out of 986 ZIP codes with data in Indiana, these are the lowest-ranked areas for reliability score. See also: National Least Reliable Water Systems in America | All Indiana Rankings

Statistic	Value
ZIP codes ranked	986
Lowest value	15/100
Median value	65/100
State	Indiana

100 Lowest-Ranked ZIP Codes

Rank	ZIP Code	City	State	Reliability Score	Safety Score
1	47283	Westport	IN	15/100	45/100
2	47633	Poseyville	IN	15/100	40/100
3	47862	Montezuma	IN	15/100	50/100
4	47952	Kingman	IN	15/100	33/100
5	46133	Glenwood	IN	21/100	51/100
6	46510	Claypool	IN	21/100	61/100
7	46085	Fishers	IN	24/100	56/100
8	46799	Zanesville	IN	24/100	56/100
9	47960	Monticello	IN	24/100	47/100
10	46290	Indianapolis	IN	25/100	56/100
11	47175	Taswell	IN	27/100	45/100
12	46352	La Porte	IN	29/100	82/100
13	46111	Brooklyn	IN	30/100	65/100
14	46986	Swayzee	IN	30/100	48/100
15	47380	Ridgeville	IN	30/100	55/100
16	47670	Princeton	IN	30/100	64/100
17	46580	Warsaw	IN	31/100	51/100
18	46581	Warsaw	IN	31/100	61/100
19	46582	Warsaw	IN	31/100	51/100
20	47374	Richmond	IN	31/100	53/100
21	47375	Richmond	IN	31/100	58/100
22	47874	Rosedale	IN	31/100	72/100
23	46349	Lake Village	IN	32/100	74/100
24	47123	Grantsburg	IN	32/100	82/100
25	47136	Lanesville	IN	32/100	61/100
26	46104	Arlington	IN	34/100	60/100
27	46350	La Porte	IN	34/100	77/100
28	47024	Laurel	IN	34/100	81/100
29	47172	Sellersburg	IN	34/100	60/100
30	47265	North Vernon	IN	34/100	68/100
31	47513	Birdseye	IN	34/100	44/100
32	47801	Terre Haute	IN	34/100	77/100
33	47802	Terre Haute	IN	34/100	63/100
34	47803	Terre Haute	IN	34/100	73/100
35	47804	Terre Haute	IN	34/100	73/100
36	47805	Terre Haute	IN	34/100	73/100
37	47807	Terre Haute	IN	34/100	78/100
38	47808	Terre Haute	IN	34/100	78/100
39	47809	Terre Haute	IN	34/100	77/100
40	47811	Terre Haute	IN	34/100	77/100
41	47812	Terre Haute	IN	34/100	77/100
42	47840	Centerpoint	IN	34/100	74/100
43	47993	Williamsport	IN	34/100	68/100
44	46750	Huntington	IN	35/100	47/100
45	47167	Salem	IN	35/100	53/100
46	47401	Bloomington	IN	35/100	48/100
47	47402	Bloomington	IN	35/100	53/100
48	47403	Bloomington	IN	35/100	48/100
49	47404	Bloomington	IN	35/100	53/100
50	47405	Bloomington	IN	35/100	45/100
51	47406	Bloomington	IN	35/100	45/100
52	47407	Bloomington	IN	35/100	45/100
53	47408	Bloomington	IN	35/100	53/100
54	47640	Hazleton	IN	35/100	77/100
55	47974	Perrysville	IN	35/100	42/100
56	47535	Freelandville	IN	36/100	79/100
57	46303	Cedar Lake	IN	37/100	58/100
58	46383	Valparaiso	IN	37/100	71/100
59	46384	Valparaiso	IN	37/100	81/100
60	46385	Valparaiso	IN	37/100	76/100
61	47036	Oldenburg	IN	37/100	82/100
62	47341	Fountain City	IN	37/100	66/100
63	47920	Battle Ground	IN	37/100	51/100
64	46915	Burlington	IN	38/100	61/100
65	47639	Haubstadt	IN	38/100	69/100
66	46793	Waterloo	IN	39/100	75/100
67	47832	Bloomingdale	IN	39/100	77/100
68	46148	Knightstown	IN	40/100	63/100
69	46201	Indianapolis	IN	40/100	51/100
70	46202	Indianapolis	IN	40/100	56/100
71	46203	Indianapolis	IN	40/100	46/100
72	46204	Indianapolis	IN	40/100	56/100
73	46205	Indianapolis	IN	40/100	46/100
74	46206	Indianapolis	IN	40/100	56/100
75	46207	Indianapolis	IN	40/100	48/100
76	46208	Indianapolis	IN	40/100	51/100
77	46209	Indianapolis	IN	40/100	48/100
78	46211	Indianapolis	IN	40/100	48/100
79	46213	Indianapolis	IN	40/100	48/100
80	46214	Indianapolis	IN	40/100	51/100
81	46216	Indianapolis	IN	40/100	48/100
82	46217	Indianapolis	IN	40/100	46/100
83	46218	Indianapolis	IN	40/100	51/100
84	46219	Indianapolis	IN	40/100	46/100
85	46220	Indianapolis	IN	40/100	41/100
86	46221	Indianapolis	IN	40/100	46/100
87	46222	Indianapolis	IN	40/100	51/100
88	46223	Indianapolis	IN	40/100	48/100
89	46224	Indianapolis	IN	40/100	46/100
90	46225	Indianapolis	IN	40/100	51/100
91	46226	Indianapolis	IN	40/100	46/100
92	46227	Indianapolis	IN	40/100	46/100
93	46228	Indianapolis	IN	40/100	46/100
94	46229	Indianapolis	IN	40/100	51/100
95	46230	Indianapolis	IN	40/100	48/100
96	46231	Indianapolis	IN	40/100	56/100
97	46234	Indianapolis	IN	40/100	51/100
98	46235	Indianapolis	IN	40/100	56/100
99	46236	Indianapolis	IN	40/100	56/100
100	46237	Indianapolis	IN	40/100	51/100

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: 2026-06-04.

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.