National Water Supply and Drainage Board, Galle Road, Ratmalana
Block No. 9, B.M.I.C.H. Premises, Bauddhaloka Mawatha, Colombo 07
120/5, Wijerama Mawatha,, Colombo 07
2nd Floor, “Sethsiripaya”, Sri Jayawardanapura Kotte, Battaramulla
330, Thalawathugoda Road, Madiwela, Sri Jayawadrenapura
500, T.B. Jayah Mawatha,, Colombo 10
Level 11, East Tower World Trade Centre, Colombo 01