Table of Contents
- What is TDS in water?
- Why TDS level is important in drinking water?
- Effects of high TDS levels in drinking water
- Effects of low TDS levels in drinking water
- Drinking water TDS Chart
- Cities in India with safe water TDS levels
In this blog, we will discuss in detail what TDS is, its impact on health, it’s optimum range and how it affects drinking water quality. You will also learn about the regulations like BIS and WHO that set parameters, check and regularise drinking water TDS in India.
What is TDS in water?
We keep hearing about TDS, what does it mean and how does it effect our water? TDS stands for Total Dissolved Solids, which is the measurement of all inorganic and organic substances that are present in the water. These substances can include minerals, salts, metals, and other impurities that can dissolve in water. TDS is measured in parts per million (ppm) or milligrams per litre (mg/L).
Why TDS level is important in drinking water
TDS level in drinking water is an important parameter that determines the quality of water. High TDS in water can indicate the presence of harmful contaminants such as lead, arsenic, and fluoride, which can have adverse health effects. On the other hand, low TDS levels in drinking water can indicate that the water lacks essential minerals that are important for human health.
The World Health Organization (WHO) recommends a TDS level of less than 300 mg/L for drinking water. However, this value can vary depending on local regulations and standards.
Also Read: Why are we concerned with the pH of Drinking water?
Effects of high TDS levels in drinking water
High TDS range in water can have several negative impacts on human health. Some of the effects of high TDS levels are:
- Increased risk of gastrointestinal diseases: If drinking water TDS levels is high, there is an increased risk of gastrointestinal diseases such as diarahea, nausea, and vomiting.
- Kidney problems: Extreme TDS levels in water can lead to the formation of kidney stones, which can cause severe pain and other complications.
- Cardiovascular diseases: Your heart health might be at risk if TDS levels in your drinking water is high. There is an increased risk of cardiovascular diseases such as hypertension and atherosclerosis.
- Dental problems: High level of TDS can cause dental problems such as dental caries and enamel erosion.
Effects of low TDS levels in drinking water
Low TDS range in drinking water can also have negative impacts on human health. Some of the effects of low TDS levels are:
Mineral deficiency: Low TDS levels in drinking water can lead to mineral deficiencies in the body. Minerals such as calcium, magnesium, and potassium are essential for human health and are found missing in water with low TDS limit.
Digestive problems: Low TDS in drinking water can cause digestion problems such as constipation and irritable bowel syndrome.
Increased risk of heart disease: Limited TDS levels in drinking water have been linked to an increased risk of heart disease.
What drinking water TDS means for your health?
Drinking Water TDS Chart
| TDS Level (mg/L) | Water Quality | Health Implications |
| 50-300 | Excellent | Safe for drinking |
| 300-600 | Good | Safe for drinking |
| 600-900 | Fair | Safe for drinking |
| 900-1200 | Poor | May cause laxative effect in some people |
| 1200-2000 | Very Poor | Not suitable for drinking on a regular basis |
| Above 2000 | Unacceptable | Not suitable for drinking |
According to the Bureau of Indian Standards (BIS), the permissible limit for TDS in drinking water is 500 mg/L. However, the World Health Organization recommends a TDS level of less than 300 mg/L for drinking water. Minimum TDS of drinking water should not go below 50 ppm.
Find below information on the top 5 cities in India with safe water TDS levels based on available data up to 2021. It is important to note that the water quality can vary over time and may change based on various factors such as season, weather, and treatment methods.
Top 5 cities in India with safe water TDS levels in 2021:
| City | Test conducted by | TDS Range | Comments |
| Chennai | Bureau of Indian Standards (BIS) | less than 300 mg/L | Excellent and safe for consumption. |
| Mumbai | Maharashtra Pollution Control Board (MPCB | 260-320 mg/L | safe for consumption |
| Bengaluru | Bureau of Indian Standards (BIS) | 100-600 mg/L | safe for consumption |
| Hyderabad | Maharashtra Pollution Control Board (MPCB | 100-700 mg/L | safe for consumption |
| Delhi | Bureau of Indian Standards (BIS) | 150-400 mg/L | safe for consumption |
It is important to note that these values may have changed since 2021 and may also vary within different parts of the respective cities. It is recommended to consult with the local water authorities or conduct independent water testing to ensure safe water consumption.
Note that the TDS level is just one parameter that determines the quality of water. Other factors such as pH, presence of harmful contaminants, and microbial content should also be considered while determining the quality of drinking water.
Also Read: Water Pollution And Its Effect On Water Quality In India