- Water pollution is any chemical, biological, or physical change in water quality that has a harmful effect on living organism or makes water unsuitable for desired used.
- It has been suggested that it is the leading worldwide cause of deaths and diseases, and that it accounts for the deaths of more than 14,000 people daily.
Chemical pollutants especially pesticides and fertilizers drain into lakes and ponds through runoffs and have negative impacts on the aquatic life of lakes/ponds/rivers. Eutrophication (pronounced you-tro-fi-KAY-shun) is a natural process that occurs in an aging lake or pond as that body of water gradually builds up its concentration of plant nutrients. Cultural or artificial eutrophication occurs when human activity introduces increased amounts of these nutrients, which speed up plant growth and eventually choke the lake of all of its animal life.
Sewage treatment plant (STP)
Waste water from millions of households/complexes and industries enters the sewage system which is then goes to sewage plants for treatment before the treated effluent makes its way to streams, rivers or sea. The wastewater contains both solid and dissolved pollutants and chemicals and includes fecal matter, urine, food residues, and sanitary stuffs. It is essential to treat wastewater before discharging it to the water bodies. Discharging wastewater without treating might result in the spread of various water-borne and infectious diseases.
Irony in India is that no more than 30% of sewage generated by 377 million people flows through treatment plants. About 70% of wastewater is randomly dumped into rivers, lakes, wells, and sea, polluting 75% of the country's water bodies (IndiaSpend Analysis 2016)
Industrial effluent treatment plant (ETP) is essential to purify the wastewater that comes from different types of manufacturing industries such as textile, ternary, dyes, chemical, pharmaceuticals, etc.