The quality of water in Hauz Khas lake had become hazardous for birds and fish. Tarun Sebastian Nanda, a civil and environmental engineer has taken up a project of cleaning the Hauz Khas lake in Delhi by using artificially constructed floating wetlands. These wetlands act as biofilters and are far easier to maintain than mechanical treatment plants. Wetlands purify water through natural processes where aquatic plants act as bio-filters. Plants absorb phosphates and nitrates from the water and roots help to put back oxygen into the water.
Constructed wetlands are a cost-effective method of treating wastewater and polluted water bodies. These are low cost solutions and can be easily made or replicated.