Tampa hard water: 12.3 grains per gallon
Tampa tap water is very hard: about 12.3 grains per gallon (211 mg/L) on average. That number comes from the Tampa Water Department's 2025 water quality report (PDF, opens in new tab).
Tampa water hardness
Grains per gallon, from the Tampa Water Department 2025 water quality report. Sacramento river water shown for comparison.
Where does Tampa water come from?
The city's report says Tampa Water Department customers rely on the Hillsborough River as their main source. In 2025 the city also used 980 million gallons of treated water that it had stored underground in aquifers and recovery wells. When it needs more, the city buys water from Tampa Bay Water.
Florida's rivers and aquifers run through limestone. That rock is rich in calcium, which is the main mineral behind hardness. Live outside city limits? Hillsborough County and nearby cities run their own systems, so check their reports for your number.
What 12.3 grains per gallon means at home
- White crust on faucets, shower heads and glass doors
- Spots on dishes and glassware
- Scale inside water heaters, kettles and coffee makers
- Soap and shampoo that do not lather well
Do you need a water softener in Tampa?
For most homes, a softener is worth it. At about 12 grains per gallon, scale builds up fast on fixtures and inside appliances. A softener stops that. Test your own tap first so the system is sized for your home.
See what a softener costs, or read reverse osmosis vs. a water softener if you also want filtered drinking water.
Get a free water test in Tampa
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Book my free water testCommon questions
Is Tampa water hard?
Yes. The Tampa Water Department's 2025 report says the average total hardness of its finished water was 211 mg/L, or 12.3 grains per gallon. Anything over 10.5 grains per gallon is very hard.
Where does Tampa get its water?
The city's report says the Hillsborough River is the main source. In 2025 the city also used water stored in its aquifers and recovery wells, and it can buy water from Tampa Bay Water when needed.
Is hard water a safety problem in Tampa?
No. Hardness is calcium and magnesium. It causes scale and spots, not illness. For safety results, read the full city report.
Keep reading
DataWater hardness by cityHow hard the tap water is in US cities, from each utility report.
City dataHouston water hardness: what the city report saysAbout 7.9 grains per gallon on average. Hard.
GuideHow much does a water softener cost installed?Installed price ranges, running costs, and what drives the price.
GuideReverse osmosis vs. water softener: which one do you need?They do different jobs. Here is how to pick.