estimated 6 percent of the total area, and at least 8 percent of the area has classified as open space. As of 2017, the total volume of water harvested was 339 mcft and groundwater recharge was 170 mcft. Administration Chennai city is governed by the Greater Chennai Corporation (formerly "Corporation of Madras"), which was established in 1688. It is the oldest surviving municipal corporation in India and the second oldest surviving corporation in the world. In 2011, the jurisdiction of the Chennai Corporation was expanded from to an area of , dividing into three regions—North, South and Central, which covers 200 wards. The corporation is headed by a mayor, an office presently occupied by Priya Rajan. The Mayor and councillors of the city are elected through a popular vote by the residents. While the city limit was expanded in 2011, the revised population is yet to be officially announced. The Chennai Metropolitan Development Authority (CMDA) is the nodal agency responsible for planning and development of Chennai Metropolitan Area, which is spread over an area of , covering the Chennai district and parts of Tiruvallur, Kanchipuram and Chengalpattu districts. The larger suburbs are governed by town municipalities and the smaller ones are governed by town councils called panchayats. Under the gamut of the CMDA are 5 parliamentary and 28 assembly constituencies. The CMDA has drafted an additional Master Plan that aims to develop satellite townships around the city. The city's contiguous satellite towns include Mahabalipuram in the south, Chengalpattu and Maraimalai Nagar in the southwest, and Sriperumpudur, Arakkonam, Kanchipuram and Tiruvallur to the west. Chennai, as the capital of the state of Tamil Nadu, houses the state executive and legislative headquarters primarily in the Secretariat Buildings in the Fort St George campus. The Madras High Court, is the highest judicial authority in the state, whose jurisdiction extends across Tamil Nadu and Puducherry. Chennai has three parliamentary constituencies—Chennai North, Chennai Central and Chennai South—and elects 24 Members of the Legislative Assembly (MLAs) to the state legislature. Law and order The Greater Chennai Police is the main law enforcement agency in the city, with a jurisdiction of over catering to over 8.5 million people. It consists of 121 police stations and is headed by a commissioner of police. The Greater Chennai Police is a division of the Tamil Nadu Police, and the administrative control lies with the Tamil Nadu Home Ministry. Chennai City