GREATER NOIDA, June 4 -- A comprehensive drive to clean overhead water tanks across various sectors and localities of Greater Noida started on Tuesday to ensure a clean and safe drinking water supply, officials said on Tuesday. The sanitation drive that started with the overhead tank in Sigma IV, will last till July 10 and cover multiple sectors including Chi, Omega, and Knowledge Park among others. While cleaning of underground water reservoirs is carried out by authorities routinely, this initiative includes systematic cleaning of overhead tanks handled by the Greater Noida authority. These tanks directly supply water to households as well, officials said. "On the days when tank cleaning is scheduled in a particular sector, morning water supply will continue as usual but water pressure in afternoon and evening is expected to be low... A date-wise schedule for cleaning has been released by water department. It will be available on Greater Noida authority's website," said general manager(projects) AK Singh. The move, officials said, is aimed at maintaining hygiene and safeguarding public health, particularly during summer months when water consumption is high and the risk of waterborne illnesses hikes. The authority has also arranged water tankers which can be requested in case of disruption, officials said. "Tank cleaning is a preventive step to ensure residents get hygienic water, especially in summer when demand is high and contamination risks increase. We appeal to citizens to cooperate by using water judiciously and storing it in advance. Locals are requested to cooperate during this essential maintenance drive," said assistant chief executive officer Prerna Singh. In case of water shortage, residents can contact on 7983604110, 9811839456, 9873763995, 9899331572, 9654302913, 8130504019, 8377911380, 9871090100, 8859285804, and they will be assisted, officials said. To be sure, there have been several instances of illness among residents due to contaminated water supply in Greater Noida high rises. In April, around 500 residents of Ajnara Homes Society fell ill....