evidence: In urban areas it is necessary to have high elevated storage facilities, such as storage water tanks on top of buildings, elevated water towers and ground storage reservoirs on top of hills or high elevated ground. At present Colombo city uses around 300,000 m3 of water on the average per day. Accordingly, the minimum high-elevated storage has to be 100,000m3 to 125,000m3, and ground-storage facilities should be 200,000 m3 to 175,000 m3. After the completion of the ongoing GCWRP project, the elevated storage in Colombo city will total up to 82,500 m3. After commissioning of Maligakanda new reservoir, a decision has to be taken ‘with regard to the Maligakanda rectangular concrete reservoir, which is around 125 years old, along with piping and valves. For this purpose a panel of experts may have to be appointed by the NWSDB for ascertaining their condition. This would need this reservoir and the components to be isolated from the distribution network for checking the condition for stability, whether they are suitable for further use or, whether they would have to be replaced with a new reservoir along with the other components.