Sodium
Worth knowing if you are on a restricted diet, and the number a water softener quietly raises.
- Measured in
- mg/L
No range is shown because none is published as a standard. EPA issues a drinking water advisory aimed at people on sodium-restricted diets, which is guidance rather than an enforceable limit, so this platform records the number and does not grade it.
What it is
Sodium is naturally present in most water and rises from road salt, seawater intrusion, septic discharge and — most controllably — from a water softener, which works by exchanging the calcium and magnesium in hard water for sodium.
Why it matters
For most people sodium in water is a small fraction of dietary intake and is not worth thinking about. For people on a medically restricted sodium diet it can matter, and it is the one they are least likely to have accounted for. EPA publishes a drinking water ADVISORY level aimed at exactly that group, but it is guidance rather than an enforceable standard, which is why no band is shown on this page.
How to measure it
A laboratory panel. If you own a softener, take the sample from a tap downstream of it — that is the water you actually drink.
Certified laboratory, mail-in kit
- How trustworthy
- Reference grade
- Cost
- Most expensive
- Effort
- Careful sampling, then days or weeks of waiting
You are posted bottles and instructions, you fill them exactly as told, and you post them back. Weeks later a report arrives with figures nobody has to interpret by eye. This is what a result you intend to act on should be built from.
Standard on any general chemistry panel, and normally reported alongside chloride, which helps identify whether the source is salt or a softener.
Where to find it: State-certified drinking water laboratories; your state's certification officer keeps the list, and many public health departments will point you at one.
Your utility's annual water quality report
- How trustworthy
- Reference grade
- Cost
- Free
- Effort
- A few minutes of reading
Every community water system in the US has to publish one each year, free, listing what it found and what the limits are. It is real laboratory data about the water leaving the plant and travelling the mains. What it cannot describe is your own plumbing.
Public systems often publish sodium precisely because of the restricted-diet question, even though it is not a regulated contaminant.
Where to find it: Your water bill, your supplier's website, or the EPA's index of reports. It is also called a Consumer Confidence Report or CCR.
Taking the sample
For several of these the sample is where the error is, and no instrument recovers from a bad one.
- • Sample downstream of any softener, and ideally take a second sample from an unsoftened outdoor tap. The difference between the two is exactly what the softener is adding.
Further reading: US EPA: Consumer Confidence Reports, the annual report every community water system publishes
If it is too low
Nothing to act on. Low sodium in water is not a deficiency; diet supplies far more.
- • No action needed.
If it is too high
Worth discussing with a doctor if anyone in the household is on a sodium-restricted diet. A softener is the most likely cause and the easiest to work around.
- • If you have a softener, plumb the kitchen cold tap to bypass it. That gives you unsoftened water to drink and cook with and leaves the rest of the house soft.
- • Potassium chloride can replace sodium chloride in the softener, which trades one ion for another that most diets are not restricting.
- • Reverse osmosis at the drinking tap removes it.
Common questions
Does a water softener make water salty?
It raises the sodium, though rarely enough to taste. How much depends on how hard the incoming water was: a softener adds sodium in proportion to the calcium and magnesium it removes, so very hard water produces the largest increase.
Should I worry about sodium in my drinking water?
For most people it is a minor contributor next to food. It matters if you are on a medically restricted sodium intake, and in that case it is worth knowing the number and bypassing the softener at the kitchen tap.
WiseWaterGauge helps you record and understand your own readings. It is not a substitute for a certified laboratory test, and nothing here is medical or regulatory advice. If a health parameter is out of range, confirm it with an accredited lab and speak to your water provider.