Hawaii
The 7 hardness figures we’ve verified run from 1.0 to 6.0 grains per gallon, with a median of 1.0; 0% are hard or very hard.
How the 7 figures spread across the bands
- Soft 0
- Slightly hard 6
- Moderately hard 1
- Hard 0
- Very hard 0
- Hardness
- 1.0 gpg medianAverage 2.0 gpg (34 ppm), from 1.0 to 6.0. Each published figure counts once in the average, median and spread; a figure published as a range is shown as its range and isn't averaged.
- Coverage
- 7 places7 listings as published
- Disinfectant
- 0 of 4use chloramine; 4 use chlorine
Every place we have
Sources are each city’s water quality report or its utility. Gather the listings up by place or by the water system that serves them, or see every listing as published; open a group to see what’s in it.
7 places
| On the scale | Disinfectant | Sources | Ask Aqua | ||
|---|---|---|---|---|---|
Maui No source linked
|
6.0 gpg110 ppm, moderately hard | SoftSlightly hardModerately hardHardVery hardModerately hard 6.0 gpg |
– | ||
Honolulu No source linked
|
2.0 gpg34 ppm, slightly hard | SoftSlightly hardModerately hardHardVery hardSlightly hard 2.0 gpg |
Chlorine | Disinfectant | |
Pearl City No source linked
|
2.0 gpg32 ppm, slightly hard | SoftSlightly hardModerately hardHardVery hardSlightly hard 2.0 gpg |
Chlorine | Disinfectant | |
Hilo No source linked
|
1.0 gpg17 ppm, slightly hard | SoftSlightly hardModerately hardHardVery hardSlightly hard 1.0 gpg |
Chlorine | Disinfectant | |
Kaanapali No source linked
|
1.0 gpg17 ppm, slightly hard | SoftSlightly hardModerately hardHardVery hardSlightly hard 1.0 gpg |
– | ||
Kailua No source linked
|
1.0 gpg22 ppm, slightly hard | SoftSlightly hardModerately hardHardVery hardSlightly hard 1.0 gpg |
Chlorine | Disinfectant | |
Waikola No source linked
|
1.0 gpg10 ppm, slightly hard | SoftSlightly hardModerately hardHardVery hardSlightly hard 1.0 gpg |
– |
Missing your city? Aquatell researches cities on request from the utility’s own reports, usually within a week. A note on a figure says what we found when we checked it: units that didn’t agree, another page with a different figure, a range.
What to do about it
Hard water
Above about 3.5 grains per gallon, scale builds in water heaters, fixtures and appliances. A softener sized for your hardness and household removes it for the whole house.
Chlorine or chloramine
Standard carbon removes chlorine’s taste and smell. Chloramine lasts longer in the pipes and needs catalytic carbon to remove it.
Not sure what you need?
Aqua knows these figures and Aquatell’s treatment charts, and can size a system for your home.
