The short answer: Jacksonville water can reach about 22 grains per gallon, which is very hard. Tampa averages about 10.8 grains per gallon and swings with the seasons. Orlando comes in around 7.5 grains per gallon, which is still considered hard. If you're on a private well, the only way to know is to test.
How Is Water Hardness Measured?
Water hardness is usually measured in grains per gallon (gpg) or milligrams per liter (mg/L), which is the same as parts per million (ppm). One grain per gallon equals 17.1 mg/L.
The U.S. Geological Survey groups water into four levels:
| Level | mg/L (ppm) | Grains per gallon | What you may notice |
|---|---|---|---|
| Soft | 0–60 | 0–3.5 | What a water softener produces |
| Moderately hard | 61–120 | 3.6–7.0 | Some spotting, little visible scale |
| Hard | 121–180 | 7.1–10.5 | Scale on fixtures, soap that won't lather |
| Very hard | Over 180 | Over 10.5 | Persistent scale and appliance wear |
How Hard Is the Water in My City?
What if I live in Jacksonville?
Jacksonville draws its water from the Floridan aquifer, and JEA reports hardness by ZIP code. In the hardest parts of the system, hardness reaches up to 372 mg/L, or about 22 grains per gallon. That puts much of Jacksonville in the very hard range.
What if I live in Tampa?
The City of Tampa draws most of its water from the Hillsborough River instead of the aquifer. It's still hard, averaging 185 mg/L, or about 10.8 grains per gallon. Hardness also changes with the seasons, from around 8 grains per gallon in the wet season up to about 17 in the dry season.
What if I live in Orlando?
Orlando Utilities Commission draws from the Floridan aquifer and reports hardness around 129 ppm, or about 7.5 grains per gallon. That's in the hard range, and it's enough to leave scale on fixtures and inside water heaters over time.
For more detail on your area, see our Jacksonville, Tampa and Orlando pages.
My City Says My Water Meets All Standards. Why Is It Still Hard?
Both things can be true. Jacksonville, Tampa and Orlando all treat their water to meet federal health-based drinking water standards. Those standards are about safety. Hardness isn't regulated as a safety issue, so a utility can deliver perfectly legal water that still scales your water heater and spots your dishes.
What If I Have a Private Well?
Private wells aren't tested by a utility, so there's no annual report to look up. Well water in Florida often carries hardness along with other common concerns, such as iron that can cause orange or brown stains, or a sulfur smell that some people describe as "rotten eggs."
Because every well is different, a water test is the best way to understand what's in your water before choosing a treatment system. Otter tests both city water and well water.
How Hard Is Your Water?
Your city's average is a good starting point, but the water at your own tap is what matters. Otter will test your water at your kitchen sink, show you the hardness reading on the spot and give you one flat installed price in writing.