Austin hard water: what it does to your home

Austin's own city water is moderately hard. Austin Water's 2025 report averages 93 ppm, about 5.4 grains per gallon. But a lot of the suburbs are much harder, with some reporting 250 ppm or more. Hard water won't hurt you, but it leaves scale on faucets, spots on glass, and buildup inside water heaters. Here's how hard your water really is, what it does to your home, and when a softener is worth it.

What hard water actually is

Hard water is water with a lot of dissolved calcium and magnesium. Those minerals come from rock. Central Texas sits on a lot of limestone, so water around here picks up plenty of them on the way to your tap.

You can't see the minerals while the water is in the glass. You see them when the water dries or heats up. That's when they come out of the water and stick to whatever's nearby.

How hardness is measured

You'll see hardness listed two ways:

• ppm or mg/L. Parts per million and milligrams per liter are the same thing for water. Utility reports usually use these.
• Grains per gallon, or gpg. Softener companies usually use this. One grain per gallon is about 17.1 ppm.

The USGS uses a simple scale:

| Hardness | ppm (mg/L) | | --- | --- | | Soft | 0 to 60 | | Moderately hard | 61 to 120 | | Hard | 121 to 180 | | Very hard | over 180 |

You can read more on the USGS water hardness page.

How hard is the water around Austin?

This is where it gets interesting. Hardness varies a lot depending on your utility and its source. Here's what the latest reports say.

| City | Utility | Reported hardness | | --- | --- | --- | | Austin | Austin Water | 70 to 126 ppm, average 93 (2025) | | Westlake Hills | Water District 10 | average 102 ppm (2025) | | Cedar Park | City of Cedar Park | 183 ppm (2025) | | Lakeway | Lakeway MUD | 184 ppm (2025) | | Lakeway area | Travis County WCID 17 | 182 to 185 ppm (2025) | | Georgetown | Georgetown Utility Systems | about 176 to 178 or 309 to 320 mg/L by plant | | Round Rock | City of Round Rock | about 250 mg/L, very hard (2025) | | Kyle | City of Kyle | 275 to 295 mg/L (2025) | | Manor | City of Manor wells | 297 ppm (2021 sample) |

A few cities, including Leander, Bee Cave, Buda, and Liberty Hill, don't publish a single hardness number in their reports. Pflugerville lists the minerals but not a total. Our city pages link to each report.

Why Austin is softer than the suburbs

Austin Water uses lime softening at its treatment plants. That process takes out some of the hardness before the water leaves the plant. Water District 10 in West Lake Hills buys Austin's water, so it's similar.

Many suburbs use different sources or different treatment. Lake Travis water in Cedar Park and Lakeway comes in right around 183 ppm. Round Rock blends Lake Georgetown water with other sources. Kyle blends Edwards Aquifer wells with river water and other groundwater. The result can be close to three times Austin's average.

So if you moved from central Austin to Round Rock or Kyle and suddenly can't keep your faucets clean, it's not you. It's the water.

What hard water does to your home

Hard water is a maintenance problem, not a safety problem. But it adds up.

Fixtures and glass

This is the part everyone notices first.

• White crust around faucets and on showerheads
• Spots on dishes and glasses after the dishwasher
• Cloudy glass shower doors that never quite get clean
• Rings in toilets and sinks

Showerheads can clog as scale builds up inside the little holes, which hurts water pressure.

Water heaters

Heat pulls minerals out of water fast. In a tank water heater, scale settles at the bottom. In a tankless unit, it builds up inside the heat exchanger.

Most manufacturers recommend flushing or descaling on a schedule, and hard water makes that more important. If you have a tankless unit, check the manual. Many specifically call out water hardness.

Appliances

Dishwashers, washing machines, coffee makers, kettles, and ice makers all deal with scale. You'll see it as white buildup on heating elements and inside small water lines.

Soap and laundry

Hard water makes soap work harder. Shampoo and dish soap don't lather as easily. People often use more detergent to make up for it, and soap scum shows up faster in the shower.

How to tell how hard your water is

You have three easy options.

1. Read your utility's water quality report. Look for "hardness" or "total hardness." If it's not there, look for calcium and magnesium. Each of our city pages links to the right report.
2. Use test strips. Cheap and quick, but not very precise.
3. Get an in home water test. A local installer measures hardness right at your tap, along with chlorine or chloramine and total dissolved solids. It's free.

Testing at your own tap is worth it if your city has more than one source. In Georgetown, hardness depends on which plant serves your area. In Manor and Hutto, reported ranges are very wide.

What you can do about it

Clean what's already there

For existing buildup, white vinegar or a scale remover works on faucets, showerheads, and glass. Soak a showerhead in vinegar to clear clogged holes. This handles the symptom but not the cause.

A water softener

A water softener removes calcium and magnesium through a process called ion exchange. It's the most effective fix, and it's what most people mean when they talk about treating hard water.

It needs salt added every so often. Modern units only regenerate when they need to, so they use much less salt than older ones.

Salt free conditioners

Salt free systems don't remove hardness minerals. Some types change how the minerals behave so less scale sticks inside pipes and heaters. You'll still see spots on glass. They're lower upkeep, but the results are different. We cover this in more detail on our hard water treatment page.

RO for drinking water

A reverse osmosis system at the kitchen sink removes most dissolved minerals from your drinking water. It doesn't help the rest of the house, but it's great for coffee, tea, and ice. Many homes pair a softener with RO.

When is a softener worth it?

Here's a simple way to think about it.

Under about 120 ppm (7 grains). That's Austin and Westlake territory. A softener is optional. Lots of homes do fine with a whole house carbon filter for chloramine and RO for drinking water. If scale really bugs you, a softener still helps.

Around 180 ppm (about 10 to 11 grains). Cedar Park, Lakeway, and parts of Georgetown. You'll notice scale and spots. A softener makes a clear difference.

Over 250 ppm (14 grains or more). Round Rock, Kyle, parts of Georgetown, and some Manor wells. Scale builds fast. Most homeowners who care about fixtures and appliances end up with a softener.

Also consider:

• Do you have a tankless water heater you want to protect?
• How much does spotting on glass and dishes bother you?
• Is there already a softener loop in your garage? Many newer homes in Leander, Liberty Hill, and Round Rock have one.

Most homes that soften also add carbon filtration for chloramine. Our chloramine guide explains why.

Bottom line

Austin's own water is moderately hard. Many surrounding cities are hard to very hard. Hard water isn't a safety issue, but it costs you time scrubbing and wears on fixtures and appliances that heat water.

Not sure where your home falls? Request a free in home water test. A local installer will call to set a time, measure hardness at your tap, go over your utility's report, and tell you whether a softener is worth it.