Least Reliable Water Systems in Pennsylvania

Out of 2,184 ZIP codes with data in Pennsylvania, these are the lowest-ranked areas for reliability score. See also: National Least Reliable Water Systems in America | All Pennsylvania Rankings

Statistic	Value
ZIP codes ranked	2,184
Lowest value	10/100
Median value	75/100
State	Pennsylvania

100 Lowest-Ranked ZIP Codes

Rank	ZIP Code	City	State	Reliability Score	Safety Score
1	18419	Factoryville	PA	10/100	37/100
2	16229	Freeport	PA	15/100	27/100
3	16342	Polk	PA	15/100	32/100
4	18330	Effort	PA	19/100	55/100
5	18818	Friendsville	PA	19/100	54/100
6	16110	Adamsville	PA	20/100	58/100
7	16726	Cyclone	PA	20/100	39/100
8	17040	Landisburg	PA	20/100	45/100
9	18332	Henryville	PA	20/100	57/100
10	18405	Beach Lake	PA	20/100	62/100
11	19083	Havertown	PA	20/100	10/100
12	17078	Palmyra	PA	23/100	42/100
13	18372	Tannersville	PA	23/100	33/100
14	15012	Belle Vernon	PA	24/100	71/100
15	15059	Midland	PA	25/100	42/100
16	15474	Point Marion	PA	25/100	45/100
17	15737	Elmora	PA	25/100	65/100
18	16049	Parker	PA	25/100	15/100
19	17315	Dover	PA	25/100	45/100
20	18076	Red Hill	PA	25/100	31/100
21	18425	Greeley	PA	25/100	54/100
22	18458	Shohola	PA	25/100	63/100
23	18970	Trumbauersville	PA	25/100	53/100
24	18414	Dalton	PA	26/100	45/100
25	17771	Trout Run	PA	27/100	31/100
26	17020	Duncannon	PA	28/100	26/100
27	18813	Brooklyn	PA	28/100	58/100
28	19341	Exton	PA	28/100	48/100
29	16682	Sproul	PA	29/100	27/100
30	17047	Loysville	PA	29/100	43/100
31	17850	Montandon	PA	29/100	52/100
32	18708	Shavertown	PA	29/100	38/100
33	15003	Ambridge	PA	30/100	54/100
34	17745	Lock Haven	PA	30/100	41/100
35	19342	Glen Mills	PA	30/100	51/100
36	15437	Farmington	PA	31/100	72/100
37	18360	Stroudsburg	PA	31/100	32/100
38	18426	Greentown	PA	31/100	55/100
39	18438	Lakeville	PA	31/100	72/100
40	17070	New Cumberland	PA	32/100	43/100
41	18039	Durham	PA	32/100	61/100
42	19543	Morgantown	PA	32/100	69/100
43	15331	Ellsworth	PA	33/100	65/100
44	16115	Darlington	PA	33/100	36/100
45	15436	Fairchance	PA	34/100	81/100
46	15717	Blairsville	PA	34/100	73/100
47	15863	Stump Creek	PA	34/100	73/100
48	16423	Lake City	PA	34/100	73/100
49	16872	Rebersburg	PA	34/100	57/100
50	16875	Spring Mills	PA	34/100	55/100
51	17236	Mercersburg	PA	34/100	60/100
52	17763	Ralston	PA	34/100	52/100
53	18470	Union Dale	PA	34/100	60/100
54	18707	Mountain Top	PA	34/100	55/100
55	19348	Kennett Square	PA	34/100	50/100
56	19468	Royersford	PA	34/100	52/100
57	15333	Fredericktown	PA	35/100	61/100
58	15411	Addison	PA	35/100	65/100
59	16052	Prospect	PA	35/100	37/100
60	16125	Greenville	PA	35/100	64/100
61	16159	West Middlesex	PA	35/100	55/100
62	16940	Nelson	PA	35/100	48/100
63	17744	Linden	PA	35/100	38/100
64	17765	Roaring Branch	PA	35/100	45/100
65	18212	Ashfield	PA	35/100	48/100
66	18349	Pocono Manor	PA	35/100	26/100
67	18353	Saylorsburg	PA	35/100	43/100
68	18444	Moscow	PA	35/100	32/100
69	18447	Olyphant	PA	35/100	21/100
70	18448	Olyphant	PA	35/100	16/100
71	18603	Berwick	PA	35/100	21/100
72	18615	Falls	PA	35/100	46/100
73	18801	Montrose	PA	35/100	26/100
74	18976	Warrington	PA	35/100	55/100
75	16341	Pleasantville	PA	36/100	59/100
76	16823	Bellefonte	PA	36/100	51/100
77	18657	Tunkhannock	PA	36/100	44/100
78	16678	Saxton	PA	37/100	56/100
79	16923	Genesee	PA	37/100	74/100
80	16941	Genesee	PA	37/100	71/100
81	17740	Jersey Shore	PA	37/100	51/100
82	17754	Montoursville	PA	37/100	54/100
83	17844	Mifflinburg	PA	37/100	59/100
84	17952	Mary D	PA	37/100	54/100
85	18651	Plymouth	PA	37/100	31/100
86	18834	New Milford	PA	37/100	51/100
87	15077	Shippingport	PA	38/100	43/100
88	18066	New Tripoli	PA	38/100	38/100
89	17507	Bowmansville	PA	39/100	53/100
90	18240	Nesquehoning	PA	39/100	43/100
91	18427	Hamlin	PA	39/100	70/100
92	15552	Meyersdale	PA	40/100	34/100
93	15658	Ligonier	PA	40/100	33/100
94	15824	Brockway	PA	40/100	64/100
95	15864	Summerville	PA	40/100	56/100
96	16230	Hawthorn	PA	40/100	57/100
97	16656	Irvona	PA	40/100	48/100
98	16929	Lawrenceville	PA	40/100	48/100
99	17562	Paradise	PA	40/100	53/100
100	17572	Ronks	PA	40/100	41/100

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.

Least Reliable Water Systems in Pennsylvania — 2026

100 Lowest-Ranked ZIP Codes

Methodology

Frequently Asked Questions

What does a low water reliability score mean?

How is reliability different from safety score?

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