If you live in St. Peters and run a water softener, you have probably heard that softening trades the minerals that make tap water hard for sodium. That is broadly true, and it is a fair question to ask about your own home. This guide explains where the sodium comes from, how to find out what your system adds, and what to do with that information.
Why softening adds sodium
A softener removes hardness minerals by passing water through resin beads that hold onto calcium and magnesium. When the resin needs recharging, the system flushes it with a salt solution. The beads release the hardness minerals and take on sodium in exchange. Some of that sodium stays in the water that reaches your taps. How much depends on how hard your incoming water is, how the unit is set, and how much water your household uses.
St. Peters tap water is described in public reports as hard, so most softened homes here will see some added sodium. Local reports also list sodium and chloride among the things they track, which is a reminder that sodium is already in the source water before any softener touches it. The water at your cold tap carries the sodium from the supply plus whatever the softener adds.
Find the baseline first
Before you change anything, get a clear picture of what is already in your water.
- Pull the most recent water quality report from your supplier and find the sodium and chloride lines. Note the units and the year of the report.
- Check the softener's settings, including the hardness level you set it to and the regeneration schedule. A unit set to leave some hardness in the water adds less sodium than one set to remove nearly all of it.
- If you have a private well, ask an accredited lab for a sodium test on the raw water before softening, since a well's baseline does not appear in any public report.
- Test softened water at a cold tap you use for drinking or cooking, and compare that result to the raw water result if you have one.
Read a lab result without guessing
A lab report lists sodium with its units and a detection limit. Compare the softened sample to the raw sample. If the softened result is clearly higher, the difference is mostly what the softener added. If the two are similar, the sodium is coming from your source water, not the softener. Keep the report with your softener papers so you can repeat the same test later if something changes.
Decide what to do next
Most homeowners fall into one of a few situations.
- You do not track sodium for any health reason. Keep the softener at its current setting and keep your baseline results on file.
- Your clinician has asked you to track sodium intake. Ask them whether softened water changes your plan, and which tap they want you to use for drinking and cooking. This guide is not a substitute for their advice.
- You are on a sodium-restricted plan and want less added sodium. Talk with your clinician or a registered dietitian before you change the softener. Adjusting how much hardness the unit removes is one option, but the decision belongs with the person managing your diet.
- You have a private well with uncertain results. Test the raw water for the things this area is known for, including coliform bacteria, and for radium or uranium in deeper aquifers, which is worth doing in areas near the former Weldon Spring site. Make decisions about treatment after you have results.
Keep the softener record current
Sodium from a softener is not a hidden problem, but it is a figure worth knowing. Write down your settings, the date of your last lab test, and any changes to the system. A simple log makes a later question easy to answer. If a clinician, a family member, or a water report raises the topic of sodium, you will have the facts in hand instead of relying on memory.