COLOMBO (News 1st) – The National Water Supply and Drainage Board (NWSDB) announced that the water supply will be interrupted for 16 hours tomorrow (21) for several areas in Kahahena, Hanwella, Jalthara-Ranala, Kaduwela, Mapitigama, Dompe.This will be in effect from 8.00 AM to 12.00 midnight..