Capital's flood-risk increases as lakes disappear Rapid urbanisation, poor planning and inadequate oversight has seen Hanoi's lakes shrink and disappear, with experts warning that if the situation continues, the capital will face more flooding. Speaking at a conference on drainage solutions for Hanoi, Associate Pro. Dr. Bui Cong Quang from Hanoi Water Resources University said in the past, previously, the network of lakes, ponds and rivers were an integral part of Hanoi's drainage system. But total area of Hanoi lakes, excluding West Lake, have fallen by 64%. "The sharp decrease of Hanoi's lake area is based on encroachment by building construction which is the result of weak urban planning," Quang added.   A street in Hanoi flooded on May 25  Many lakes in Hanoi have shrunk or been entirely built on for construction. According to the Hanoi Department of Population and Family Planning, each year the city’s population increases by about 200,000 people, equivalent to the population of a large district. Of the new population, about 120,000 are new-born children and the rest are migrants. "The massive construction of buildings has also led to the degradation of the city's drainage system which was already out of date, with small pipes with limited capacity that can get blocked easily by sediment build-up," Quang noted. In 2010, the prime minister requested Hanoi to tighten control over the construction of high-rise apartment projects in the inner-city districts of Dong Da, Hai Ba Trung, Hoan Kiem and Ba Dinh to restrict population growth. However, since then, many projects have been built in these districts. On May 25, torrential rain flooded Hanoi after a five hour deluge, causing major traffic chaos and leaving low-lying areas submerged for over a day. Regarding this, the director of the Hanoi Drainage Company said the sudden rainfall exceeded the capacity of the city’s drainage system. The flooding on May 25 was reminiscent of the historic downpour in 2008 which caused extreme flooding in the city, killed 20 people and caused trillions of VND worth of damage, but the situation has little improved over the last eight years. Experts said Hanoi needs to protect its lakes and deal with the encroachment by building dykes. By Quang Phong,  dtinews.vn