Worst Tap Water Records in the US: Lowest Purity Scores (2024)
The water systems serving South River, NJ, Spalding County, GA and Lantana, FL have the lowest Purity Scores of the 4,194 city reports considered: the worst records on this one measure, not a safety ranking. From public EPA records (2024-12-31). It ranks the published record, not which water is safest.
South River, NJ tops this list in 2026
South River, NJ is first. Spalding County, GA, Lantana, FL, Crest Hill, IL and Sparta Twp - Lake Mohawk, NJ follow. Point Pleasant Beach, NJ and South Saint Paul, MN are last on this list.
All 25 ranked water systems
- 1South River, NJ11 flagged contaminants on recordSOUTH RIVER W DEPT · PWSID NJ1223001 · Purity Score 24/100 · Confidence: not yet published · Assessed at the water-system level
- 2Spalding County, GA11 flagged contaminants on recordSPALDING COUNTY WATER SYSTEM · PWSID GA2550036 · Purity Score 25/100 · Confidence: not yet published · Assessed at the water-system level
- 3Lantana, FL13 flagged contaminants on recordLANTANA WATER TREATMENT PLANT · PWSID FL4500784 · Purity Score 26/100 · Confidence: not yet published · Assessed at the water-system level
- 4Crest Hill, IL13 flagged contaminants on recordCREST HILL · PWSID IL1970250 · Purity Score 26/100 · Confidence: not yet published · Assessed at the water-system level
- 5Sparta Twp - Lake Mohawk, NJ11 flagged contaminants on recordSPARTA TWP WATER UTILITY - LAKE MOHAWK · PWSID NJ1918004 · Purity Score 27/100 · Confidence: not yet published · Assessed at the water-system level
- 6Atascadero, CA10 flagged contaminants on recordATASCADERO MUTUAL WATER CO · PWSID CA4010002 · Purity Score 32/100 · Confidence: not yet published · Assessed at the water-system level
- 7Florida City, FL8 flagged contaminants on recordFLORIDA CITY · PWSID FL4130255 · Purity Score 32/100 · Confidence: not yet published · Assessed at the water-system level
- 8Grafton District, MA10 flagged contaminants on recordGRAFTON WATER DISTRICT · PWSID MA2110000 · Purity Score 36/100 · Confidence: not yet published · Assessed at the water-system level
- 9Stoughton, MA10 flagged contaminants on recordSTOUGHTON WATER DEPARTMENT · PWSID MA4285000 · Purity Score 36/100 · Confidence: not yet published · Assessed at the water-system level
- 10Hastings, NE9 flagged contaminants on recordHASTINGS, CITY OF · PWSID NE3100101 · Purity Score 36/100 · Confidence: not yet published · Assessed at the water-system level
- 11South Elgin, IL13 flagged contaminants on recordSOUTH ELGIN · PWSID IL0890800 · Purity Score 39/100 · Confidence: not yet published · Assessed at the water-system level
- 12Dartmouth, MA11 flagged contaminants on recordDARTMOUTH WATER DIVISION · PWSID MA4072000 · Purity Score 39/100 · Confidence: not yet published · Assessed at the water-system level
- 13Lincoln, IL11 flagged contaminants on recordIL AMERICAN-LINCOLN · PWSID IL1075030 · Purity Score 40/100 · Confidence: not yet published · Assessed at the water-system level
- 14Auburn District, MA10 flagged contaminants on recordAUBURN WATER DISTRICT · PWSID MA2017000 · Purity Score 41/100 · Confidence: not yet published · Assessed at the water-system level
- 15Wagoner County Rwd, OK9 flagged contaminants on recordWAGONER CO. RWD #4 · PWSID OK1021529 · Purity Score 42/100 · Confidence: not yet published · Assessed at the water-system level
- 16Modesto, CA10 flagged contaminants on recordMODESTO, CITY OF · PWSID CA5010010 · Purity Score 43/100 · Confidence: not yet published · Assessed at the water-system level
- 17Lindsay, CA8 flagged contaminants on recordLINDSAY, CITY OF · PWSID CA5410006 · Purity Score 43/100 · Confidence: not yet published · Assessed at the water-system level
- 18Big Sandy District, KY10 flagged contaminants on recordBIG SANDY WATER DISTRICT · PWSID KY0100944 · Purity Score 43/100 · Confidence: not yet published · Assessed at the water-system level
- 19Watertown, NY6 flagged contaminants on recordWATERTOWN CITY · PWSID NY2202346 · Purity Score 43/100 · Confidence: not yet published · Assessed at the water-system level
- 20Winnsboro, SC8 flagged contaminants on recordWINNSBORO TOWN OF (2010001) · PWSID SC2010001 · Purity Score 43/100 · Confidence: not yet published · Assessed at the water-system level
- 21Wanaque, NJ10 flagged contaminants on recordWANAQUE W DEPT. · PWSID NJ1613002 · Purity Score 44/100 · Confidence: not yet published · Assessed at the water-system level
- 22Lauderhill, FL11 flagged contaminants on recordLAUDERHILL, CITY OF · PWSID FL4060787 · Purity Score 45/100 · Confidence: not yet published · Assessed at the water-system level
- 23Raynham Center District, MA11 flagged contaminants on recordRAYNHAM CENTER WATER DISTRICT · PWSID MA4245000 · Purity Score 45/100 · Confidence: not yet published · Assessed at the water-system level
- 24South Saint Paul, MN13 flagged contaminants on recordSouth Saint Paul · PWSID MN1190020 · Purity Score 45/100 · Confidence: not yet published · Assessed at the water-system level
- 25Point Pleasant Beach, NJ7 flagged contaminants on recordPOINT PLEASANT BEACH WATER DEPARTMENT · PWSID NJ1525001 · Purity Score 45/100 · Confidence: not yet published · Assessed at the water-system level
The top 25 of 4,194 city reports are listed. Only cities with a computed Purity Score and a resolved serving system are eligible; all others are excluded.
How this snapshot is built
- How this snapshot is built
Cities ranked by their PurityMap Purity Score, a reproducible score computed only over contaminants that were actually measured in the EPA record. A lower score means more or more-severe measured exceedances, not a statement about untested contaminants.
- Reading the order
Scores reflect only measured contaminants; a city with sparse monitoring can score higher simply because less was tested. This is not an overall safety ranking.
- Exclusions
The top 25 of 4,194 city reports are shown. Only cities with a computed Purity Score and a resolved serving system are eligible; all others are excluded.
Comparable does not mean complete.
This ranking compares water systems on one measure. It never replaces a full system report, a city-resolution check, or a certified household test, and missing monitoring is excluded, never scored as favourable.