HCM City authorities are working on a plan to encourage homeowners to build their own small reservoirs to collect rainwater in an aim to prevent flooding. The plan, developed by the Centre of Water Management and Climate Change under HCM City National University, will be assessed by the city's Department of Planning and Architecture. Under the project, reservoirs, both small and large, would be built in residential areas, industrial parks, schools and hospitals. The plan calls for many small reservoirs instead of many large reservoirs that would take up too much space. Flooding has worsened in recent years, especially during heavy rains. Stored rainwater from the reservoirs at houses, schools and hospitals could also be used to water trees, wash vehicles or clean homes. Ho Long Phi, Director of the Centre of Water Management and Climate Change, said such reservoirs could be built at an affordable cost of 2-3 million VND (90-134 USD). A 2-3 cubic-metre reservoir could be built on the house's top floor, with a plastic or stainless steel container used for water storage. The containers would be connected to a pipe that would transfer rainwater to the sewer system. Phi said the city should offer residents financial support from the flood-prevention programme, as most households were reluctant to build reservoirs on their own. He also recommended that the Government first launch a pilot programme in new residential areas like District 2, 7, 9 and 12 and in areas that have the worst flooding. Phi said the reservoir model was not a new one. In Germany, for example, the law requires that homeowners have a reservoir to store rainwater to prevent flooding. Dr Le Huy Ba, former Head of the Institute of Environmental Management and Technology under the Industrial University of HCM City, said the Government should also offer advice on reservoir design and technology. Dao Minh Duc, a resident in Thu Duc district, said reservoirs should be built underground instead of on the top floor of houses. He suggested the use of a one cubic-metre stainless steel container, which would cost 5-6 million VND (225-270 USD). Tran Thi Thuy Trang, of Linh Dong Ward, Thu Duc district, said: "I'm afraid we can't afford to build the reservoir unless we are financially supported by the Government." HCM City recently decided to spend 950 billion VND (42.6 million USD) to build three large-scale reservoirs in the most flooded areas. Covering an area of 100 hectares, the three reservoirs would hold millions of cubic metres of water and resolve flooding in District 4 and Tan Binh and Thu Duc districts. The largest would be the 600 billion VND (26.9 million USD) Go Dua reservoir (95ha) in Thu Duc district, followed by the 300 billion VND (13.45 million USD) Khanh Hoi reservoir in District 4 and the 50 billion VND (2.24 million USD) Bau Cat lake in Tan Binh district. Construction of the reservoirs would take place from 2016 to 2020.-VNA