1) Turning Sewage Water Into Drinkable Water

This organic water filter developed by Anto P Biju and Thomas Cyriac, is the size of an index finger, costs just Rs 10, and can convert up to 30 litres of impure water into freshwater within a few hours using activated carbon. On putting the purifier in any water container, pores from contaminated water that act as micro-reservoirs are fixed over a disc inside the cartridge. It eliminates foul smell, harmful metals and colours from the water. Moreover, the technology adds minerals that improve the immune system. The best part? The cartridge in the purifier that costs around Rs 60 has to be replaced every five years, which means there is no maintenance or recurring cost

2) Using Floating Wetlands to Make Water Bodies Pollutant-Free

Tarun Sebastian Nanda, an ecological engineer, is using a natural way to clean water bodies in Delhi through his ‘Adopt an Island’ initiative.

He is constructing floating wetlands by using aquatic plants. These plants are placed on buoyant mats made from drainage pipes and discarded soda bottles.

When the island is placed on the surface water, they absorb manganese, iron, aluminium and other contaminants through their roots and foliage, thus purifying the polluted water. These wetlands also discourage the growth of algae and help improve the overall ecosystem.

3) Treating Water With Human Hair

At just 13, Nikhilesh Das from Assam came up with an indigenous way to use human hair to clean oil spills in water.  He mixed motor oil and lubricant with water in a beaker. As the oil formed a layer on top, he deposited human hair and saw how it absorbed 90 per cent of the oil from water within 30 seconds. His innovation even won an award from former President, Pratibha Patil, in 2009.