Neela Hauz Biodiversity Park

Neela Hauz Biodiversity Park is a 3.90-hectare wetland along Aruna Asaf Ali Road in Delhi, beside Sanjay Van on the South Central Delhi Ridge. The freshwater lake at its heart once supplied water to the Rajput city of Qila Rai Pithora. By 2014 it had silted up and been encroached upon, with raw sewage draining in and water hyacinth across its surface, until concerned citizens obtained a Delhi High Court order for its restoration.

The Delhi Development Authority began work in 2015, desilting the lake, landscaping the banks and planting 15,000 native plants and shrubs, and the park opened in November 2016. Treated water now passes through a constructed wetland of oxidation points and filtration channels before entering the lake, although a 2019 test by the Delhi Jal Board found the effluent below permissible standards. More than 70 bird species were using the lake by 2016, migratory birds among them.