If you've had your well water tested and received a report showing elevated TDS, you may be wondering what that actually means for your family and your home. TDS — total dissolved solids — is a measurement of everything dissolved in your water, and in North Carolina well water, high TDS is relatively common. Here's how to make sense of it.
What Is TDS?
Total dissolved solids is a measure of the combined concentration of all dissolved substances in water — minerals, salts, metals, and other compounds. It's expressed in milligrams per liter (mg/L) or parts per million (ppm). The EPA has set a secondary standard (a guideline, not a legally enforceable limit) of 500 mg/L for drinking water. Well water in many parts of central North Carolina can exceed this level.
TDS itself isn't a single contaminant — it's an indicator of the overall dissolved load in your water. What matters most is understanding what specific compounds are contributing to that number.
What Causes High TDS in NC Well Water
In central North Carolina, elevated TDS in private wells is typically driven by:
- Calcium and magnesium (hardness minerals) from limestone and rock
formations
- Iron and manganese from soil and bedrock
- Sulfates from certain geological deposits
- Sodium and chloride from soil minerals or road salt infiltration
near roads
- Occasionally, agricultural or septic-related contamination in rural
areas
How High TDS Affects Your Home
High TDS water often has a noticeable taste — it may taste salty, bitter, or mineral-heavy depending on what's contributing to the reading. It can also:
- Accelerate scale buildup on fixtures and inside appliances
- Leave staining that varies in color depending on which minerals are
dominant
- Reduce the effectiveness of soap and detergent
- Affect the flavor of beverages made with tap water, including coffee
and tea
How to Address High TDS Well Water in NC
Reverse Osmosis for Drinking Water
If TDS is primarily a concern for your drinking and cooking water, a reverse osmosis system installed under the kitchen sink is the most effective solution. RO removes the vast majority of dissolved solids, producing consistently clean, great-tasting water at the tap. The system is compact, efficient, and low-maintenance.
Whole-Home Treatment for Specific Contaminants
If your TDS is being driven by specific contaminants — iron, hardness, manganese — targeted whole-home treatment addresses those at the source and reduces overall TDS while protecting your plumbing and appliances throughout the house.
Start with a Comprehensive Test
A raw TDS number doesn't tell you everything. A full water panel for your well identifies the specific contributors to your TDS reading and guides a targeted treatment approach. This is especially important in rural NC counties where well water composition varies significantly from property to property.