These are the questions San Antonio homeowners ask before they soften or filter their water, answered from SAWS, TCEQ, the City of San Antonio, the EPA, the USGS and the NSF/ANSI standards. If yours is not here, ask it on the contact page.
Water Filtration San Antonio is an independent referral service, not an installer or plumber. When you send the form, your details go to an independent local water treatment pro who can contact you and quote the work.
About this site
Is this a water treatment company?
No. It is an independent referral service. It does not sell, install or service equipment and does not test water. When you send the form, an independent local water treatment pro can contact you and quote the work.
What does it cost to ask?
Nothing. Sending the form is free and does not commit you to buy anything. Any price is between you and the pro: ask for it in writing.
Which areas do you cover?
San Antonio and Bexar County, inside Loop 410 and out past Loop 1604, and nearby towns such as New Braunfels, Boerne, Schertz and Helotes. Put your ZIP code or neighborhood on the form. See areas served.
San Antonio water
How hard is San Antonio water?
SAWS says the typical hardness of the water it provides ranges from 15 to 20 grains per gallon. At about 17 mg/L per grain, that is roughly 255 to 340 mg/L, very hard on the USGS scale, which starts at 180 mg/L.
Why is it so hard?
SAWS says the hardness comes from calcium carbonate found naturally in water from the Edwards and the Trinity Aquifers.
Is hard water bad for my health?
SAWS says, “Hard water is not a health hazard.” Its effects are practical: soap scum, more soap needed, and deposits on dishes, fixtures, basins and pipes.
Is San Antonio tap water safe to drink?
This site does not judge that. SAWS publishes an annual water quality report, and its download page lists the 2026 report. Read it and ask SAWS about anything in it. See the water quality guide.
I am not on SAWS. What figure do I use?
Your water bill names your supplier. Ask it for its annual water quality report and use its hardness figure. On a private well, have the water tested by a certified laboratory.
Softeners
What does a water softener do?
It removes the calcium and magnesium that make water hard. An ion exchange softener uses a resin that is recharged with sodium chloride or potassium chloride; NSF/ANSI 44 is the standard for those residential softeners.
Does a softener add salt to the water?
A salt-based softener adds a little sodium in exchange for the hardness it removes. If you are on a sodium-restricted diet, ask your doctor, and ask the installer about potassium chloride.
Is a water conditioner the same thing?
The word can mean a salt-based softener or a salt-free unit. Salt-free units are a different technology from ion exchange: ask what any salt-free unit is certified for. See the salt-free softener article.
What size softener do I need?
Hardness in grains per gallon multiplied by the gallons your household uses in a day gives the grains the softener must remove each day. Ask the installer to show you that arithmetic. More on the water softener page.
How often does a softener need service?
Follow the maker’s schedule in your owner’s manual. Keep salt in the brine tank between visits and watch for spots, crust or soap that will not lather. See softener service.
My softener stopped working. What should I check?
That there is salt and no hard crust in the brine tank, that the bypass valve is in the service position, and that the control valve has power and kept its settings. If that does not fix it, see softener repair.
Can softened water affect my water heater?
Water utilities commonly note that some softening systems can increase the corrosivity of the water, which can damage the anodes in a water heater. Ask how the softener will be set and whether the anode should be checked.
Filters and reverse osmosis
Do I need a softener and a filter?
They do different jobs. A softener removes hardness; a filter deals with taste, odor or a contaminant. TCEQ’s advice is to decide first what you want to remove, then choose a unit certified by NSF, Underwriter’s Laboratory or the Water Quality Association for it.
Which type of water filtration is best?
The one certified for the thing you want to change: NSF/ANSI 42 for aesthetic effects such as chlorine, taste and odor, NSF/ANSI 53 for health effects such as lead, NSF/ANSI 58 for reverse osmosis. See water treatment in San Antonio.
What is reverse osmosis?
In the EPA’s words, the process by which pressure forces water through a semi-permeable membrane. A point-of-use unit, under the kitchen sink, makes drinking and cooking water at one faucet.
What is the downside of reverse osmosis?
Reject water. The EPA says a typical unit sends five gallons or more down the drain per gallon treated, some up to 10; WaterSense labeled units must send 2.3 gallons or less.
Permits, licenses and cost
Do I need a permit for a softener in San Antonio?
The City of San Antonio’s Limited Service Repair permit covers replacing an existing softener or water purifier and installing one in a building already pre-plumbed for it. Other softener work needs a regular plumbing permit. Other cities set their own rules.
Who may install a softener in Texas?
Under TCEQ’s Water Treatment Specialist rule, any individual who installs, exchanges, connects, maintains or services water treatment equipment under contract needs that license unless exempt. Texas licensed plumbers are exempt. Reverse osmosis work needs Class III.
How much does a water filtration system cost?
This site prints no prices. Cost depends on the equipment, its certification and the plumbing work involved. Ask for a written, itemized quote after a water test.