Hardest Water in New Hampshire
6 cities ranked by water hardness. Manchester tops the list at 31 PPM.
New Hampshire's water hardness varies significantly by city and water source. The state average across our database is 24 PPM, which is relatively soft. Most homes do not need a water softener. 0% of cities we track in New Hampshire have hardness above 120 PPM.
Keene has the softest water at just 15 PPM. No softener is needed.
| # | City | PPM | GPG | Level | Softener? |
|---|---|---|---|---|---|
| 1 | Manchester | 31 | 1.8 | Slightly Hard | No |
| 2 | Dover | 30 | 1.8 | Slightly Hard | No |
| 3 | Nashua | 28 | 1.6 | Slightly Hard | No |
| 4 | Concord | 22 | 1.3 | Slightly Hard | No |
| 5 | Manchester South | 18 | 1.1 | Slightly Hard | No |
| 6 | Keene | 15 | 0.9 | Soft | No |
Frequently Asked Questions
What is the average water hardness in New Hampshire?
Across 6 cities in our database, the average water hardness in New Hampshire is 24 PPM (1.4 GPG). This ranges from 15 PPM in Keene to 31 PPM in Manchester.
Do I need a water softener in New Hampshire?
It depends on your city. 0% of New Hampshire cities in our database (0 of 6) have hardness above 120 PPM where a softener provides measurable benefit. Check your specific city above.
Which New Hampshire city has the softest water?
Keene has the softest water in New Hampshire at 15 PPM (0.9 GPG). No water softener is needed at this level.
What causes hard water in New Hampshire?
Hard water in New Hampshire is caused by dissolved calcium and magnesium from the local geology. Most of the state has favorable geology with granite, metamorphic, or volcanic rock that contributes minimal dissolved minerals.