In order to bring maximum area of the city under its network, the Delhi Jal Board on Sunday announced to extend sewerage facilities to seven new unauthorised colonies.The move aims at improving sanitation in these areas and it will also help in abatement of pollution in Yamuna River. According to officials, sewerage facilities have been extended in seven unauthorised colonies —Chanakya Place, Sita Puri, Keshoram Park, New Jankipuri, Jai Bharat Enclave Amar shopping complex Kakroula Moad, Bhagwati Garden extension, Uttam Nagar and Bhagwati Garden (Najafgarh Road).