Water Quality Standards: Standards of Water for Human Consumption & Water Testing

Numerous uses of water make it necessary for the survival of human life. In its pure form, water is usually tasteless, colorless and odorless. Due to all kinds of pollution, it is seldom found in its pure form. Several impurities are found in it mainly due to careless human activities.

Every year, it is estimated that about 0.5 to 1.5 million children under the age of five die in India, due to consumption of contaminated water. Maharashtra is one of the worst affected states, where approximately 0.7 million children suffer from water borne diseases, of which 1,000 die annually. The most common water borne diseases are cholera, typhoid, diarrhea, viral hepatitis A, and dysentery. 

Water Quality Standards: Types of Impurities in Water

Different types of impurities are found in water, which make it unfit for human consumption. Some of these impurities are classified below:

Physical Impurities

These are impurities are mainly caused due to soil erosion and makes the water hazy. However, these can be separated by filtration. The most common types of physical contaminants are lignins, humic acids, and micro organisms.

Mineral Impurities

These are mainly the minerals present in soil, which get dissolved in ground water or surface water. These are also known as Total Dissolved Solids (TDS). In many parts of India, water gets contaminated due to presence of fluorides, arsenic, and iron which causes fatal diseases and may result in death.

Organic Impurities

Surface water is subjected to these organic impurities comprising both plant and animal residuals and micro-organisms, which are found on the surface of the earth. Other major sources of the organic impurities are fertilizers and pesticides.

Water Quality Standards: Mandatory Requirements for Water Testing

Testing water samples of ground water is a mandatory requirement to keep track of its rate of deterioration. Most of the authorities, which supply drinking water, are equipped with water testing facilities. The strict enforcement of pollution control laws has resulted in an increase in demand for laboratory facilities for proper testing of water quality standards.

There are many private agencies, which provide wide spectrum of water testing services. The results of laboratories, accredited by National Accreditation Board for Testing and Calibration Laboratories (NABL}, are accepted by the Pollution Control Boards and other government authorities.

The NABL has a strict quality system, which includes standardized testing methods and regular audits for retention and renewal of the certification.

Water Quality Standards: Bureau of Indian Standards (BIS) 105000 Standards for Drinking Water

Drinking water standard that apply to India is that of BIS 105000-1991 standard. Here are some essential characteristics that are set by BIS for the water to be acceptable for human consumption: