Out of 504 ZIP codes with data in Maine, these are the lowest-ranked areas for reliability score. See also: National Least Reliable Water Systems in America | All Maine Rankings
| Statistic | Value |
|---|---|
| ZIP codes ranked | 504 |
| Lowest value | 10/100 |
| Median value | 65/100 |
| State | Maine |
100 Lowest-Ranked ZIP Codes
| Rank | ZIP Code | City | State | Reliability Score | Safety Score |
|---|---|---|---|---|---|
| 1 | 04664 | Sullivan | ME | 10/100 | 33/100 |
| 2 | 04677 | Sorrento | ME | 10/100 | 33/100 |
| 3 | 04414 | Brownville | ME | 15/100 | 49/100 |
| 4 | 04863 | Vinalhaven | ME | 15/100 | 58/100 |
| 5 | 04496 | Winterport | ME | 20/100 | 66/100 |
| 6 | 04640 | Hancock | ME | 20/100 | 45/100 |
| 7 | 04988 | Unity | ME | 20/100 | 58/100 |
| 8 | 04605 | Ellsworth | ME | 25/100 | 55/100 |
| 9 | 04649 | Jonesport | ME | 25/100 | 59/100 |
| 10 | 04684 | Surry | ME | 25/100 | 56/100 |
| 11 | 04464 | Monson | ME | 26/100 | 51/100 |
| 12 | 04071 | Raymond | ME | 30/100 | 43/100 |
| 13 | 04578 | Wiscasset | ME | 30/100 | 56/100 |
| 14 | 04758 | Mars Hill | ME | 30/100 | 51/100 |
| 15 | 04238 | Hebron | ME | 35/100 | 48/100 |
| 16 | 04282 | Turner | ME | 35/100 | 56/100 |
| 17 | 04419 | Carmel | ME | 35/100 | 51/100 |
| 18 | 04901 | Waterville | ME | 35/100 | 38/100 |
| 19 | 04903 | Waterville | ME | 35/100 | 39/100 |
| 20 | 04350 | Litchfield | ME | 38/100 | 63/100 |
| 21 | 04937 | Fairfield | ME | 39/100 | 58/100 |
| 22 | 04967 | Pittsfield | ME | 39/100 | 57/100 |
| 23 | 04040 | Harrison | ME | 40/100 | 64/100 |
| 24 | 04422 | Charleston | ME | 40/100 | 55/100 |
| 25 | 04424 | Danforth | ME | 40/100 | 79/100 |
| 26 | 04652 | Lubec | ME | 40/100 | 77/100 |
| 27 | 04658 | Milbridge | ME | 40/100 | 79/100 |
| 28 | 04681 | Stonington | ME | 40/100 | 62/100 |
| 29 | 04693 | Winter Harbor | ME | 40/100 | 60/100 |
| 30 | 04429 | Holden | ME | 41/100 | 67/100 |
| 31 | 04614 | Blue Hill | ME | 41/100 | 42/100 |
| 32 | 04634 | Franklin | ME | 41/100 | 62/100 |
| 33 | 04420 | Castine | ME | 42/100 | 61/100 |
| 34 | 04421 | Castine | ME | 42/100 | 66/100 |
| 35 | 04230 | East Poland | ME | 43/100 | 57/100 |
| 36 | 04274 | Poland | ME | 43/100 | 30/100 |
| 37 | 04009 | Bridgton | ME | 45/100 | 56/100 |
| 38 | 04037 | Fryeburg | ME | 45/100 | 46/100 |
| 39 | 04090 | Wells | ME | 45/100 | 45/100 |
| 40 | 04401 | Bangor | ME | 45/100 | 52/100 |
| 41 | 04402 | Bangor | ME | 45/100 | 57/100 |
| 42 | 04743 | Fort Kent | ME | 45/100 | 46/100 |
| 43 | 04854 | Owls Head | ME | 45/100 | 71/100 |
| 44 | 04947 | Kingfield | ME | 45/100 | 54/100 |
| 45 | 04668 | Princeton | ME | 46/100 | 79/100 |
| 46 | 04750 | Limestone | ME | 46/100 | 59/100 |
| 47 | 04751 | Limestone | ME | 46/100 | 59/100 |
| 48 | 04250 | Lisbon | ME | 47/100 | 63/100 |
| 49 | 04239 | Jay | ME | 48/100 | 61/100 |
| 50 | 04055 | Naples | ME | 49/100 | 38/100 |
| 51 | 04093 | Buxton | ME | 49/100 | 60/100 |
| 52 | 04280 | Sabattus | ME | 49/100 | 65/100 |
| 53 | 04070 | Scarborough | ME | 50/100 | 60/100 |
| 54 | 04074 | Scarborough | ME | 50/100 | 54/100 |
| 55 | 04079 | Harpswell | ME | 50/100 | 57/100 |
| 56 | 04220 | Buckfield | ME | 50/100 | 46/100 |
| 57 | 04427 | Corinth | ME | 50/100 | 60/100 |
| 58 | 04443 | Guilford | ME | 50/100 | 52/100 |
| 59 | 04628 | Dennysville | ME | 50/100 | 81/100 |
| 60 | 04660 | Mount Desert | ME | 50/100 | 57/100 |
| 61 | 04662 | Northeast Harbor | ME | 50/100 | 61/100 |
| 62 | 04843 | Camden | ME | 50/100 | 69/100 |
| 63 | 04856 | Rockport | ME | 50/100 | 75/100 |
| 64 | 04922 | Burnham | ME | 50/100 | 72/100 |
| 65 | 04101 | Portland | ME | 51/100 | 62/100 |
| 66 | 04102 | Portland | ME | 51/100 | 62/100 |
| 67 | 04103 | Portland | ME | 51/100 | 62/100 |
| 68 | 04104 | Portland | ME | 51/100 | 67/100 |
| 69 | 04109 | Portland | ME | 51/100 | 67/100 |
| 70 | 04112 | Portland | ME | 51/100 | 62/100 |
| 71 | 04122 | Portland | ME | 51/100 | 62/100 |
| 72 | 04123 | Portland | ME | 51/100 | 62/100 |
| 73 | 04124 | Portland | ME | 51/100 | 62/100 |
| 74 | 04539 | Bristol | ME | 52/100 | 69/100 |
| 75 | 04042 | Hollis Center | ME | 53/100 | 68/100 |
| 76 | 04630 | East Machias | ME | 53/100 | 81/100 |
| 77 | 04254 | Livermore Falls | ME | 54/100 | 50/100 |
| 78 | 04289 | West Paris | ME | 54/100 | 68/100 |
| 79 | 04769 | Presque Isle | ME | 54/100 | 60/100 |
| 80 | 04915 | Belfast | ME | 54/100 | 76/100 |
| 81 | 04011 | Brunswick | ME | 55/100 | 57/100 |
| 82 | 04236 | Greene | ME | 55/100 | 66/100 |
| 83 | 04263 | Leeds | ME | 55/100 | 68/100 |
| 84 | 04416 | Bucksport | ME | 55/100 | 62/100 |
| 85 | 04450 | Kenduskeag | ME | 55/100 | 67/100 |
| 86 | 04655 | Machiasport | ME | 55/100 | 76/100 |
| 87 | 04666 | Pembroke | ME | 55/100 | 78/100 |
| 88 | 04679 | Southwest Harbor | ME | 55/100 | 65/100 |
| 89 | 04745 | Frenchville | ME | 55/100 | 60/100 |
| 90 | 04849 | Lincolnville | ME | 55/100 | 72/100 |
| 91 | 04940 | Farmington Falls | ME | 55/100 | 64/100 |
| 92 | 04944 | Hinckley | ME | 55/100 | 56/100 |
| 93 | 04969 | Plymouth | ME | 55/100 | 64/100 |
| 94 | 03901 | Berwick | ME | 57/100 | 59/100 |
| 95 | 04221 | Canton | ME | 57/100 | 59/100 |
| 96 | 04463 | Milo | ME | 57/100 | 61/100 |
| 97 | 04479 | Sangerville | ME | 57/100 | 65/100 |
| 98 | 04572 | Waldoboro | ME | 57/100 | 66/100 |
| 99 | 04740 | Easton | ME | 57/100 | 63/100 |
| 100 | 04742 | Fort Fairfield | ME | 57/100 | 59/100 |
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.
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