Least Reliable Water Systems in Indiana — 2026

Out of 980 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	980
Lowest value	15/100
Median value	67/100
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	46510	Claypool	IN	16/100	61/100
6	46133	Glenwood	IN	21/100	51/100
7	46580	Warsaw	IN	21/100	51/100
8	46582	Warsaw	IN	21/100	51/100
9	46037	Fishers	IN	24/100	57/100
10	46038	Fishers	IN	24/100	57/100
11	46799	Zanesville	IN	24/100	56/100
12	47172	Sellersburg	IN	24/100	60/100
13	47960	Monticello	IN	24/100	47/100
14	46750	Huntington	IN	25/100	47/100
15	47175	Taswell	IN	27/100	45/100
16	46350	La Porte	IN	29/100	77/100
17	46111	Brooklyn	IN	30/100	65/100
18	46986	Swayzee	IN	30/100	48/100
19	47380	Ridgeville	IN	30/100	55/100
20	47670	Princeton	IN	30/100	64/100
21	47374	Richmond	IN	31/100	53/100
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	47024	Laurel	IN	34/100	81/100
28	47265	North Vernon	IN	34/100	68/100
29	47513	Birdseye	IN	34/100	44/100
30	47802	Terre Haute	IN	34/100	63/100
31	47803	Terre Haute	IN	34/100	73/100
32	47804	Terre Haute	IN	34/100	73/100
33	47805	Terre Haute	IN	34/100	73/100
34	47807	Terre Haute	IN	34/100	78/100
35	47809	Terre Haute	IN	34/100	77/100
36	47840	Centerpoint	IN	34/100	74/100
37	47993	Williamsport	IN	34/100	68/100
38	47167	Salem	IN	35/100	53/100
39	47401	Bloomington	IN	35/100	48/100
40	47403	Bloomington	IN	35/100	48/100
41	47404	Bloomington	IN	35/100	53/100
42	47405	Bloomington	IN	35/100	45/100
43	47406	Bloomington	IN	35/100	45/100
44	47408	Bloomington	IN	35/100	53/100
45	47640	Hazleton	IN	35/100	77/100
46	47974	Perrysville	IN	35/100	42/100
47	47535	Freelandville	IN	36/100	79/100
48	46303	Cedar Lake	IN	37/100	58/100
49	46383	Valparaiso	IN	37/100	71/100
50	46385	Valparaiso	IN	37/100	76/100
51	47036	Oldenburg	IN	37/100	82/100
52	47341	Fountain City	IN	37/100	66/100
53	47368	Parker City	IN	37/100	61/100
54	47920	Battle Ground	IN	37/100	51/100
55	46915	Burlington	IN	38/100	61/100
56	47639	Haubstadt	IN	38/100	69/100
57	46793	Waterloo	IN	39/100	75/100
58	47832	Bloomingdale	IN	39/100	77/100
59	46041	Frankfort	IN	40/100	64/100
60	46148	Knightstown	IN	40/100	63/100
61	46201	Indianapolis	IN	40/100	51/100
62	46202	Indianapolis	IN	40/100	56/100
63	46203	Indianapolis	IN	40/100	46/100
64	46204	Indianapolis	IN	40/100	56/100
65	46205	Indianapolis	IN	40/100	46/100
66	46208	Indianapolis	IN	40/100	51/100
67	46214	Indianapolis	IN	40/100	51/100
68	46216	Indianapolis	IN	40/100	48/100
69	46217	Indianapolis	IN	40/100	46/100
70	46218	Indianapolis	IN	40/100	51/100
71	46219	Indianapolis	IN	40/100	46/100
72	46220	Indianapolis	IN	40/100	41/100
73	46221	Indianapolis	IN	40/100	46/100
74	46222	Indianapolis	IN	40/100	51/100
75	46224	Indianapolis	IN	40/100	46/100
76	46225	Indianapolis	IN	40/100	51/100
77	46226	Indianapolis	IN	40/100	46/100
78	46227	Indianapolis	IN	40/100	46/100
79	46228	Indianapolis	IN	40/100	46/100
80	46229	Indianapolis	IN	40/100	51/100
81	46231	Indianapolis	IN	40/100	56/100
82	46234	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: 2026-04-13.

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.