New Jersey water systems
Hardness is measured by the water system, not by the town. New Jersey municipalities mostly buy treated water from a regional supplier, which is why dozens of towns publish an identical figure — they are all downstream of the same plant. These pages hold the system-level readings once, in full.
49 systems currently serve the towns on file. Each page lists every municipality on that system alongside the complete reported panel: hardness, disinfectant residual, sodium, chloride, sulfate, fluoride, manganese, iron, pH and total dissolved solids, cited to the report they were read from.
| System | Hardness | Classification | Towns |
|---|---|---|---|
| Coastal North SystemNJ American Water — Coastal North System, 2025 CCR (PWS ID NJ1345001). | 4.8 gpg | Moderately Hard | 36 |
| Short Hills SystemNJ American Water — Short Hills System, 2025 CCR (PWS ID NJ0712001). | 9.8 gpg | Hard | 27 |
| Delaware/Western SystemNJ American Water — Delaware/Western System, 2025 CCR (PWS ID NJ0327001). | 7.5 gpg | Hard | 25 |
| Roxbury SystemNJ American Water — Roxbury System, 2025 CCR (PWS ID NJ1436002). | 9.9 gpg | Hard | 5 |
| Washington SystemNJ American Water — Washington System, CCR. | 18.9 gpg | Very Hard | 5 |
| Mount Holly SystemNJ American Water — Mount Holly System, 2025 CCR (PWS ID NJ0323001). | 6.9 gpg | Moderately Hard | 4 |
| Bridgeport SystemNJ American Water — Bridgeport System, 2025 CCR (PWS ID NJ0809001). | 7.4 gpg | Hard | 3 |
| PVWC systemPassaic Valley Water Commission — PVWC system, CCR. | 4.7 gpg | Moderately Hard | 3 |
| Belvidere SystemNJ American Water — Belvidere System, CCR. | 15.4 gpg | Very Hard | 2 |
| Harrison SystemNJ American Water — Harrison System, CCR. | 8.2 gpg | Hard | 2 |
| ITC/County Oaks SystemNJ American Water — ITC/County Oaks System, CCR. | 9.6 gpg | Hard | 2 |
| Ocean City SystemNJ American Water — Ocean City System, CCR. | 5.1 gpg | Moderately Hard | 2 |
| Penns Grove SystemNJ American Water — Penns Grove System, CCR. | 6.7 gpg | Moderately Hard | 2 |
| Shorelands SystemNJ American Water — Shorelands System, 2025 CCR (PWS ID NJ1345001). | 4.3 gpg | Moderately Hard | 2 |
| Bloomfield Township municipal systemBloomfield Twp CCR 2024 — Bloomfield Township municipal system, CCR. | 2.6 gpg | Slightly Hard | 1 |
| Crossroads at Oldwick SystemNJ American Water — Crossroads at Oldwick System, CCR. | 13 gpg | Very Hard | 1 |
| Deep Run SystemNJ American Water — Deep Run System, CCR. | 5.6 gpg | Moderately Hard | 1 |
| East Orange municipal systemCity of East Orange — East Orange municipal system, CCR. | 25.9 gpg | Very Hard | 1 |
| Four Seasons at Chester SystemNJ American Water — Four Seasons at Chester System, CCR. | 18.3 gpg | Very Hard | 1 |
| Frenchtown SystemNJ American Water — Frenchtown System, CCR. | 10.4 gpg | Hard | 1 |
| Gloucester City municipal systemCity of Gloucester — Gloucester City municipal system, CCR. | 5.7 gpg | Moderately Hard | 1 |
| Jackson Township MUAJackson Township MUA CCR 2024 — Jackson Township MUA, CCR. | 5 gpg | Moderately Hard | 1 |
| Lakewood municipal systemLakewood — Lakewood municipal system, Water Quality Report. | 5.9 gpg | Moderately Hard | 1 |
| Liberty SystemNJ American Water — Liberty System, CCR. | 5.4 gpg | Moderately Hard | 1 |
| Little Falls SystemNJ American Water — Little Falls System, CCR. | 3.7 gpg | Moderately Hard | 1 |
| Little Falls SystemNJ American Water — Little Falls System, CCR. | 3.7 gpg | Moderately Hard | 1 |
| Mahwah municipal systemMahwah — Mahwah municipal system, Water Quality Report. | 14.6 gpg | Very Hard | 1 |
| Middlesex Water Company systemMiddlesex Water Company CCR 2025 — Middlesex Water Company system, CCR. | 4.6 gpg | Moderately Hard | 1 |
| Mount Holly SystemNJ American Water — Mount Holly System, 2025 CCR (PWS ID NJ0323001). | 6.9 gpg | Moderately Hard | 1 |
| Mount Olive/West Jersey SystemNJ American Water — Mount Olive/West Jersey System, CCR. | 9.4 gpg | Hard | 1 |
| New Egypt SystemNJ American Water — New Egypt System, CCR. | 6 gpg | Moderately Hard | 1 |
| Newark municipal systemCity of Newark CCR (2020 data) — Newark municipal system, CCR. | 2.7 gpg | Slightly Hard | 1 |
| North Jersey District Water SupplyNJ District Water Supply Commission — North Jersey District Water Supply, CCR. | 8.8 gpg | Hard | 1 |
| Ocean City SystemNJ American Water — Ocean City System, CCR. | 5.1 gpg | Moderately Hard | 1 |
| Orange municipal systemCity of Orange CCR 2025 — Orange municipal system, CCR. | 14.3 gpg | Very Hard | 1 |
| Parsippany-Troy Hills municipal systemParsippany Twp CCR 2025 — Parsippany-Troy Hills municipal system, CCR. | 21.1 gpg | Very Hard | 1 |
| Penns Grove SystemNJ American Water — Penns Grove System, CCR. | 6.7 gpg | Moderately Hard | 1 |
| South Orange Village systemSouth Orange Village — South Orange Village system, CCR. | 9.8 gpg | Hard | 1 |
| Trenton Water WorksTrenton Water Works CCR 2024 — Trenton Water Works, CCR. | 4.3 gpg | Moderately Hard | 1 |
| Union Beach SystemNJ American Water — Union Beach System, 2025 CCR (PWS ID NJ1345001). | 5.1 gpg | Moderately Hard | 1 |
| Veolia Bayonne SystemVeolia Bayonne CCR 2024 — Veolia Bayonne System, CCR. | 3 gpg | Slightly Hard | 1 |
| Veolia Hackensack SystemVeolia Hackensack — Veolia Hackensack System, CCR. | 8 gpg | Hard | 1 |
| Veolia Hackensack SystemVeolia Hackensack — Veolia Hackensack System, CCR. | 6.6 gpg | Moderately Hard | 1 |
| Veolia SystemVeolia Jersey City — Veolia System, CCR. | 4.8 gpg | Moderately Hard | 1 |
| Vincentown SystemNJ American Water — Vincentown System, CCR. | 7 gpg | Hard | 1 |
| Vincentown SystemNJ American Water — Vincentown System, CCR. | 7 gpg | Hard | 1 |
| Wayne Township municipal systemWayne Township CCR 2025 — Wayne Township municipal system, CCR. | 3 gpg | Slightly Hard | 1 |
| Western SystemNJ American Water — Western System, 2025 CCR (PWS ID NJ0327001). | 7.5 gpg | Hard | 1 |
| Whiting municipal systemWhiting — Whiting municipal system, Water Quality Report. | 3.5 gpg | Moderately Hard | 1 |
Looking for one municipality instead? Browse New Jersey by county or search the full data table.