Safe TDS for Drinking Water in India

Introduction: Understanding TDS and Water Safety in India

In a country as vast and diverse as India, ensuring safe and healthy drinking water is a challenge that varies by region, source, and treatment method. One crucial indicator of water quality is TDS—Total Dissolved Solids. Whether you're sourcing water from a municipal supply, borewell, or tanker, understanding the safe TDS for drinking water in India is key to ensuring your family consumes healthy water every day.

TDS impacts everything from taste and mineral content to potential health risks. In this guide, we’ll help you understand what TDS is, how it affects your drinking water, the best TDS for RO water, and how to maintain optimal levels using the right TDS in water purifier solutions.

1. What is TDS in Water?

TDS, or Total Dissolved Solids, refers to the combined concentration of organic and inorganic substances in water. These include essential minerals such as:

• Calcium

• Magnesium

• Potassium

• Sodium

• Bicarbonates

• Chlorides

• Sulfates

TDS is measured in milligrams per liter (mg/L) or parts per million (ppm). While some TDS in water is beneficial, extremely high or low levels can cause taste, health, and appliance-related issues.

TDS originates from natural sources like soil and rocks, but it can also enter the water from sewage, industrial runoff, fertilizers, and urban waste, making regular monitoring essential.

2. Why TDS Level is Important in Drinking Water?

The TDS level in drinking water is a major determinant of:

• Taste: Water with very low TDS tastes flat or acidic; high TDS can taste salty or metallic.

• Health: Some dissolved solids like calcium and magnesium are essential; others, like heavy metals or high sodium, are harmful.

• Appliance Longevity: Water with high TDS can lead to scaling in pipes and water purifiers, reducing their efficiency.

A safe range ensures you get the right balance between purity and essential mineral content. That's why the BIS recommends a TDS level of up to 500 mg/L for safe drinking water in India.

3. Safe TDS for Drinking Water in India (BIS Guidelines)

According to the Bureau of Indian Standards (BIS IS:10500):

• Ideal TDS Level: Up to 300 mg/L

• Maximum Acceptable Limit: 500 mg/L

• Above 500 mg/L: Not acceptable unless no other source is available, and even then, only under regulatory approval

For perspective:

• <50 mg/L: Too low — lacks essential minerals

• 50–150 mg/L: Acceptable for people with mineral-rich diets

• 150–300 mg/L: Ideal for most households

• 300–500 mg/L: Safe but may affect taste

• >500 mg/L: Generally considered unsafe for long-term use

4. Effects of High TDS Levels in Drinking Water

Excessively high TDS (above 500 mg/L) can have the following effects:

• Health Risks: Excess sodium can increase blood pressure; nitrates may affect infants; heavy metals like lead or arsenic can be toxic.

• Bad Taste/Odor: Water may taste salty, bitter, or metallic.

• Appliance Damage: High TDS leads to limescale buildup in purifiers, kettles, and water heaters.

• Clogged Filters: Reduces efficiency and life of RO membranes and filters.

Also Read - What is the Minimum TDS for Drinking Water? A Complete Guide

5. Effects of Low TDS Levels in Drinking Water

While low TDS might sound safer, water with very low mineral content (below 50 mg/L) isn't ideal:

• Flat Taste: Water becomes tasteless and less refreshing.

• Lack of Essential Minerals: Missing out on calcium, magnesium, and potassium may lead to deficiencies.

• Poor Hydration: Electrolyte imbalance may affect how water is absorbed by your body.

RO water without a TDS controller can often fall below the healthy threshold, which is why it's important to monitor and adjust accordingly.

6. Best TDS for RO Water: How RO Affects TDS

Reverse Osmosis (RO) is a common purification method, but it drastically reduces TDS—sometimes down to as low as 20–30 mg/L. While this removes harmful contaminants, it can also strip beneficial minerals.

So, what’s the best TDS for RO water?

• Ideal TDS after RO purification: Between 80–150 mg/L

• With TDS Controller or Mineral Cartridge: Ensures essential minerals like calcium and magnesium are reintroduced

Look for RO systems with built-in TDS controllers or mineralizers to balance safety and taste.

7. TDS in Water Purifier: What You Need to Know

A good water purifier doesn’t just remove impurities — it maintains a healthy TDS level too.

Common Types of TDS Control in Water Purifiers:

• Manual TDS Controller: Adjusts the proportion of raw and purified water

• Mineral Cartridge: Reintroduces essential minerals after purification

• Automatic Sensors: Smart purifiers that auto-regulate TDS levels

You should regularly measure TDS in water purifier output using a TDS meter to ensure it’s in the recommended range.

8. Drinking Water TDS Chart

Here’s a simplified chart to help you understand what different TDS levels mean:

9. Cities in India with Safe Water TDS Levels

The TDS levels of drinking water vary widely across Indian cities. Here’s a snapshot:

These values may vary by neighborhood and season. It's always wise to test your local water supply’s TDS before selecting a purifier.

10. How to Check TDS Level in Your Drinking Water

There are two main ways to check the TDS level in drinking water:

1. Digital TDS Meter

   • Affordable and easy to use

   • Gives instant readings in ppm

   • Insert into a water sample and wait for reading

2. Laboratory Water Test

   • More accurate

   • Can test for heavy metals and chemical contaminants

   • Recommended if water tastes odd or looks unclear

11. Tips to Maintain Safe TDS Levels at Home

To ensure you always have safe TDS in drinking water:

• Use RO + UV + UF purifiers with a TDS controller

• Install mineral cartridges if using RO systems

• Test TDS monthly using a digital meter

• Clean and replace filters on schedule

• Avoid mixing raw and treated water manually—let your purifier balance it

These steps will help maintain the right mineral content and keep the water safe for long-term use.

Also Read - Is 25 TDS Safe for Drinking Water?

12. Conclusion: What’s the Ideal TDS for Your Family?

The safe TDS for drinking water in India lies in the range of 150–300 mg/L, balancing safety and nutrition. While RO systems are effective, they must be equipped with TDS controllers or mineral boosters to avoid stripping water of essential nutrients.

Always remember: pure doesn’t always mean healthy. It's about striking the right balance between removing contaminants and retaining minerals. With regular testing and the right purification system, you can ensure your drinking water is safe, tasty, and health-supportive.

13. FAQs – Safe TDS for Drinking Water in India

Q1. What is the ideal TDS level for drinking water in India?
The ideal range is 150–300 mg/L, as per BIS standards.

Q2. Can I drink water with TDS less than 50?
It's not recommended for long-term use, as it lacks essential minerals.

Q3. What happens if TDS is more than 500 in drinking water?
It may cause health issues, bad taste, and appliance damage. It should be treated before consumption.

Q4. How to maintain TDS in RO water?
Use an RO purifier with a TDS controller or mineral cartridge to keep levels within the ideal range.

Q5. Which purifier is best for high TDS areas?
RO + UV or RO + UF purifiers with a TDS controller are best for areas with TDS above 500 mg/L.