Hard water in Corpus Christi, TX

Tap water hardness
198mg/L
11.6gpg
Very hard

Reported by City of Corpus Christi · September 2025

TX typical
112 mg/L
EPA health violations since 2016
2
Softener for 3 people
24k grain
Data
Utility report

The water in Corpus Christi carries roughly 198 mg/L of dissolved calcium and magnesium, or 11.6 grains per gallon. That is very hard water. The number comes from City of Corpus Christi, dated September 2025.

Corpus Christi on the hardness scale, with nearby cities
060120180240300360+TX typical 112Port Lavaca: 25 mg/LPort Lavaca 25Cuero: 26 mg/LCuero 26Edna: 36 mg/LEdna 36Yoakum: 65 mg/LYoakum 65Kingsville: 100 mg/LKingsville 100Ingleside: 143 mg/LIngleside 143Doolittle: 161 mg/LDoolittle 161Raymondville: 170 mg/LRaymondville 170Alice: 175 mg/LAlice 175Beeville: 188 mg/LBeeville 188Corpus Christi 198mg/L as calcium carbonate060120180240300360+TX 112Port Lavaca: 25 mg/LPort Lavaca 25Edna: 36 mg/LEdna 36Kingsville: 100 mg/LKingsville 100Ingleside: 143 mg/LIngleside 143Alice: 175 mg/LAlice 175Beeville: 188 mg/LBeeville 188198 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 198 mg/L, Corpus Christi is 86 mg/L above the typical Texas figure of 112. None of the 10 nearest cities we track has harder water. The range nearby runs from 25 mg/L in Port Lavaca to 188 in Beeville.

What 198 mg/L means at home

Scale forms fast here. Kettles and coffee makers need regular descaling, and showerheads clog unless you clean them.

Tank water heaters collect mineral sediment that insulates the water from the burner, so flushing the tank matters more than usual.

Dishes and glass shower doors spot easily. Soap scum and a dull film on hair or laundry are common complaints.

Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.

What to do about it

At 198 mg/L most of the trouble is scale, and only a few things deal with it.

Ion-exchange water softener

The standard whole-house fix. It swaps calcium and magnesium for sodium or potassium and needs salt plus a drain. Size it with the calculator below.

Salt-free conditioner

No salt and no drain line. It changes how minerals form scale instead of removing them, so water still tests hard.

Reverse osmosis or carbon filter

Under-sink reverse osmosis removes minerals from drinking water only. Plain carbon filters improve taste but do not soften.

Softener size for Corpus Christi

3 people × 75 gallons a day × 11.6 gpg = 2,612 grains a day. A 24,000-grain unit regenerates about every 9 days.

Size it for your household

EPA record for Corpus Christi's water system

City of Corpus Christi · PWSID TX1780003

2 health-based violations since 2016

Serves about 317,247 people from surface water.

Health-based
2
Monitoring or reporting
1
Open now
0
20162017201820192020202120222023202420252026Surface Water Treatment Rule'16'18'20'22'24'26Surface Water Treatment Rule
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Surface Water Treatment Rulefiltration and disinfection22021Resolved

Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.

Questions

Is Corpus Christi water hard?

Yes. It measures about 198 mg/L (11.6 grains per gallon), which the USGS classes as very hard.

What is the water hardness in Corpus Christi in grains per gallon?

About 11.6 gpg. One grain per gallon equals 17.1 mg/L, so 198 mg/L divided by 17.1 gives 11.6.

What size water softener do I need in Corpus Christi?

For 3 people using 75 gallons each per day, 11.6 gpg works out to about 2,612 grains a day. A 24,000-grain softener covers that with a regeneration about every 9 days.

Has the Corpus Christi water system had EPA violations?

EPA records show 2 health-based violations for City of Corpus Christi since 2016, involving Surface Water Treatment Rule. There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.

Nearby cities

All 342 cities in Texas

Hardness data: TapWaterData US Water Hardness (utility report, September 24, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.