Powai Lake is an artificial lake, situated in the northern suburb of Mumbai. The lake was created in 1891 by constructing dam between two hillocks across Mithi River. Catchment area of the lake is about 600 hectors and water spread area at full supply level is 220 hectors. The lake water is used for non-potable purposes i.e. gardening and industrial use.
In recent times, 40% of the lake has disappeared. The lake has deteriorated due to accelerated growth of residential, commercial and industrial area around the lake. The untreated disposal of sewage and garbage from nearby residential and slum colonies have affected the quality of the water.
Dissolved Oxygen level at the bottom of lake has gone low as 0.71 mg/ltr, and at the top it is 4.11mg/Ltr. The catchment of the lake has also been affected badly due to unplanned quarrying activities.
Appreciating the problem of silting, growth of water hyacinth, weed, and eutrophication of the lake, the IIT Bombay's Class of 1980 launched a "Revitalization of Powai Lake” with the objective of restoring the lake to its original pristine and sustainable form by adopting Eco-friendly designs and materials for the restoration works. In 1995, the National Lake Conservation Plan (NLCP) of the Ministry of Environment and Forests (MoE&F), reviewed the condition of Powai Lake and included the lake in its list of ten major lakes in the country for revival and improvements. The restoration/revival programme, fully funded by the NLCP, was launched in April 2002, and implemented by Bombay Municipal Corporation (BMC) now called Brihanmumbai Municipal Corporation (BMC).
In 2000 and 2002, two PILs have been filed in Bombay High Court for preservation of the Powai Lake.
The cases are still under the consideration of Bombay High Court. The followings are some of the highlights of court actions and government and citizens' actions.
Petition filed by the residents with the support of former MP Kirit Somaiya, to direct the BMC to take up the beautification and desiltation work of the lake in a systematic manner.
The restoration/revival programme, fully funded by the NLCP, was launched in April 2002, and implemented by Bombay Municipal Corporation (BMC) now called Brihanmumbai Municipal Corporation (BMC).
The Bhrashtachar Nirmulan Sanghatan (BNS) filed PIL. This was done to preserve the Chandivali and Powai lakes, which alleged-- that the hostels adjoining the Powai Lake had been built without the necessary civic permissions. After the BMC agreed, IIT was included as a party in the case.
In August, 2006, the Supreme Court had declared that protection of natural lakes and ponds is akin to honouring the most basic fundamental right the right to life, which is guaranteed under the Article 21 of the Indian Constitution.
The Powai Senior Citizens’ Association (PSCA) has come up with a self-sustainability plan for the lake in March. The group wants to convert the once-picturesque Powai Lake into an eco-tourist hot spot using maximum natural resources and minimum funds from the civic body.
The BMC has started desilting work from April 6. It has appointed around 44 contractors for clearing major and minor nullahs of silt.