Water Quality Association defines Water purification as the treatment of water to remove contaminants, impurities, and pollutants, including bacteria, viruses, and other microorganisms, to produce safe and clean drinking water.

Methods of Water Purification – 

1. Physical methods involve removing contaminants and impurities through physical processes, without altering the chemical composition of the water.example-filtration(passing water through a physical barrier to remove impurities) , sedimentation(allowing heavy particles to settle) & flotation(removing suspended solids using air bubbles).
2. Chemical methods in water purification involve using chemicals to remove contaminants and impurities from water.example-disinfection( killing microorganisms using chemicals), coagulation( removing suspended solids using chemicals) & ion exchange.
3. Biological methods in water purification utilize living organisms or their byproducts to remove contaminants and impurities from water.example-biological filtration( using microorganisms to break down organic matter) & activated sludge  (using microorganisms to treat wastewater).
4. Membrane methods in water purification utilize semipermeable membranes to remove contaminants and impurities from water.example – reverse osmosis( using semipermeable membranes to remove impurities) ,ultrafiltration( removing particles and microorganisms)  & microfiltration( removing suspended solids and bacteria) .
5. Natural methods in water purification utilize natural processes and materials to remove contaminants and impurities from water.example – solar disinfection( using sunlight to kill microorganisms) & wetlands treatment.

Water purification is a critical process that requires careful consideration of various methods and technologies. By understanding the strengths and limitations of each approach, we can work towards providing safe, clean, and sustainable water for all.