New Jersey tap water / Water hardness
Water hardness by New Jersey water system, 2025 reports
14 of the 16 water systems on this site list hardness in their 2025 water quality reports. The table shows each value as the report prints it, in milligrams per liter and grains per gallon, and what kind of value it is. New Jersey has a recommended upper limit of 250 mg/L for taste and appearance; there is no federal limit.
Hardness as printed in each system's 2025 water quality report. Select a column header to sort.
| Towns served | NJ 250 mg/L recommended · federal none | Class | What the value is | |
|---|---|---|---|---|
| Aqua New Jersey, Hamilton Square systemPWSID NJ1103001 · 2025 report | Chesterfield | Up to 49 mg/LUp to 2.9 grains per gallon | Soft | Highest resultRanged from below 10 mg/L to 49 mg/L in 2023 |
| Aqua New Jersey, Phillipsburg systemPWSID NJ2119001 · 2025 report | Greenwich Township, Lopatcong, Phillipsburg | 154 mg/L9 grains per gallon | Hard | Single valueThe utility's report lists one value for hardness, 154 mg/L (2025). |
| New Jersey American Water, Coastal North systemPWSID NJ1345001 · 2025 report | Asbury Park, Eatontown, Fair Haven, Howell, Little Silver, Long Branch, Middletown, Neptune, Ocean Township, Oceanport, Rumson, Tinton Falls, West Long Branch | Up to 140 mg/LUp to 8.2 grains per gallon | Moderately hard to hard | Highest resultRanged from 72 to 140 mg/L at the treatment plants in 2023-2025 |
| New Jersey American Water, Harrison systemPWSID NJ0808001 · 2025 report | Harrison Township | 140 mg/L8.2 grains per gallon | Hard | AverageThe utility's report lists an average of 140 mg/L at the treatment plant (2024). |
| New Jersey American Water, Liberty systemPWSID NJ2004001 · 2025 report | Elizabeth | Up to 143 mg/LUp to 8.4 grains per gallon | Soft to hard | Highest resultRanged from 53 to 143 mg/L at the treatment plant and the distribution system in 2025 |
| New Jersey American Water, Mount Holly systemPWSID NJ0323001 · 2025 report | Eastampton, Hainesport, Lumberton, Mount Holly, Westampton | 119 mg/L7 grains per gallon | Moderately hard | AverageThe utility's report lists an average of 119 mg/L at the treatment plant (2023). |
| New Jersey American Water, Ocean City systemPWSID NJ0508001 · 2025 report | Ocean City, Upper Township | 76 mg/L4.4 grains per gallon | Moderately hard | Highest resultThe report lists 76 mg/L as the highest result but a range of 76 to 100 mg/L for the same sample year (2023). |
| New Jersey American Water, Penns Grove systemPWSID NJ1707001 · 2025 report | Carneys Point, Penns Grove | 115 mg/L6.7 grains per gallon | Moderately hard | AverageThe utility's report lists an average of 115 mg/L at the treatment plant (2023). |
| New Jersey American Water, Raritan systemPWSID NJ2004002 · 2025 report | Bound Brook, Branchburg, Bridgewater, Clark, Cranford, Dunellen, Fanwood, Green Brook, Hillsborough, Hillside, Jamesburg, Kenilworth, Linden, Manville, Middlesex, Montgomery, Mountainside, North Plainfield, Piscataway, Plainfield, Plainsboro, Princeton, Raritan Borough, Raritan Township, Roselle, Roselle Park, Scotch Plains, Somerville, Union Township, Warren, Watchung, West Windsor, Westfield | Not listed in the report | ||
| New Jersey American Water, Short Hills systemPWSID NJ0712001 · 2025 report | Bedminster, Berkeley Heights, Bernards Township, Bernardsville, Chatham Township, Irvington, Long Hill, Maplewood, Millburn, New Providence, Springfield Township, Summit, West Orange | Up to 342 mg/LUp to 20 grains per gallon | Soft to very hard | Highest resultRanged from 52 to 342 mg/L at the treatment plant in 2024 |
| New Jersey American Water, Washington / Oxford systemPWSID NJ2121001 · 2025 report | Oxford, Washington Borough, Washington Township | Up to 406 mg/LUp to 23.7 grains per gallon | Very hard | Highest resultRanged from 216 to 406 mg/L at the treatment plant in 2023-2025 |
| New Jersey American Water, Western systemPWSID NJ0327001 · 2025 report | Audubon, Barrington, Cherry Hill, Cinnaminson, Delran, Edgewater Park, Haddon Heights, Haddonfield, Lindenwold, Palmyra, Riverside, Runnemede, Somerdale, Stratford, Voorhees | 128 mg/L7.5 grains per gallon | Hard | AverageThe utility's report lists an average of 128 mg/L at the treatment plant (2025). |
| Newark Water DepartmentPWSID NJ0714001 · 2025 report | Newark | Not listed in the report | ||
| Passaic Valley Water CommissionPWSID NJ1605002 · 2025 report | Clifton, Passaic, Paterson, Prospect Park | Up to 242 mg/LUp to 14.2 grains per gallon | Moderately hard to very hard | Highest resultRanged from 106 to 242 mg/L in 2025 |
| Trenton Water WorksPWSID NJ1111001 · 2025 report | Ewing, Trenton | 107 mg/L6.3 grains per gallon | Moderately hard | Single valueThe utility's report lists one value for hardness, 107 mg/L (2025). |
| Veolia Water New Jersey, Hackensack systemPWSID NJ0238001 · 2025 report | Bergenfield, Bogota, Carlstadt, Cliffside Park, Closter, Cresskill, Dumont, East Rutherford, Edgewater, Emerson, Englewood, Englewood Cliffs, Fairview, Fort Lee, Guttenberg, Hackensack, Hasbrouck Heights, Hillsdale, Leonia, Little Ferry, Maywood, New Milford, North Bergen, Norwood, Old Tappan, Oradell, Palisades Park, Paramus, Ridgefield, Ridgefield Park, River Edge, River Vale, Rochelle Park, Rutherford, Secaucus, Teaneck, Tenafly, Union City, Washington Township, Weehawken, West New York, Westwood, Wood-Ridge | Up to 210 mg/LUp to 12.3 grains per gallon | Very hard | Highest result |
Before comparing systems
- The values aren't all the same kind. Some reports give their highest hardness result, some an average, some a single value. A highest result marked "up to" is the top of the report's range, not a typical value; the "What the value is" column gives the range where the report lists one.
- Sample years differ. A 2025 report can list hardness results from earlier sampling years. The year is in the "What the value is" column.
- Ranges. Where a report lists a range, hardness differed across that system's samples, so the water at a given tap can differ from the value shown. Each system's page has the full detail from its report.
- Limits. New Jersey's standard for hardness is a 250 mg/L recommended upper limit (for taste and appearance; not enforceable). EPA has no limit for hardness.
- Not listed. The 2025 reports for the New Jersey American Water, Raritan system and Newark Water Department don't list a hardness value.
What soft, hard and very hard mean
Hardness is mostly dissolved calcium and magnesium, reported as calcium carbonate. The class labels follow the U.S. Geological Survey's guidelines:
- Soft: 0 to 60 mg/L
- Moderately hard: 61 to 120 mg/L
- Hard: 121 to 180 mg/L
- Very hard: more than 180 mg/L
Grains per gallon, the unit softener makers use, are converted from the report's mg/L value. Source for the classes: U.S. Geological Survey, Hardness of Water.
Sizing a water softener
The water softener size calculator fills in your town's hardness from the table above, then works out a softener size from your household's water use. Each town's page also lists its hardness next to its PFAS and lead results.
Every value is checked against the utility's report. See how we check the data. Found an error? Tell us.