ZIP 77001 Water Hardness
Houston, Texas · Nearest measurement: Houston (8.2 km)
Calcium Carbonate (CaCO₃)
Also: 12.9 GPG · 12.4 °dH
Annual extra cost
$600–$1,200
Water heater efficiency
-8–12% (limescale)
Dishwasher rinse aid
High setting, monthly refill
Shower filter
Strongly recommended
Hard Water in Houston: What to Do
- • Descale your water heater annually — at 221 mg/L, limescale builds at ~0.5mm/year, costing 8–12% more energy
- • Set your dishwasher's salt level to maximum (5–7) to prevent limescale on the heating element
- • Use a shower filter to reduce mineral deposition on skin and hair — especially important at this hardness level
- • Check your water softener if you have one — at this level, an improperly maintained softener may be working harder than needed
Tools for Your Area
Limescale Cost Estimator
Annual cost for Houston hardness level
Softener ROI Calculator
How long until a softener pays back
Skin & Hair Checker
Eczema and hair damage risk at 221 mg/L
Baby Formula Safety
Is your water safe for infant formula?
Pool Chemical Calculator
Doses for Houston source water
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Data note: Hardness is matched to the nearest verified municipal measurement point for the Houston area. Exact hardness may vary within a ZIP code depending on treatment plant zones. For certified data, request your Consumer Confidence Report (CCR) from your local utility — all US water utilities are required by the EPA to publish this annually.