HCMC: the fight against flooding
HCMC is one of 10 cities in the world which are categorised as being in the greatest danger of coastal flooding. With its tropical climate and geographic location at the entrance to the Nhà Bè river delta, HCMC is affected by the combined effects of rain and tide, which are accentuated by the low elevation of the land. This climatic vulnerability has recently been exacerbated as a result of robust urban growth. To counter the risk of flooding, the city has developed an ambitious water management plan and water drainage system. Alongside the development of major infrastructure (dykes, tidal gates, water pumping stations, canal dredging equipment), it is also developing an integrated approach to water-related risks in urban planning.
Lyon – a resilient city
In the Rhône-Alpes Region, floods are a relatively rare phenomenon, but when they occur they can be large-scale. For many years, people believed that urban development had “tamed” the Rhône, thereby minimising the risk of major flooding, but serious flooding such as that which took place in 1999-2000 served as a reminder of the continued risk.
Several parts of Greater Lyon are now covered by a natural disaster risk prevention plan which provides for the possibility of flooding from the Saône and Rhône rivers by adopting a preventative approach which deals with land use and construction. In addition, new techniques to consolidate the riverbanks have been developed and these help to limit the risks of flooding, while at the same time permitting the landscaping of the shorelines with stabilising trees and plants.
- 65% of HCMC’s territory is located at least 1.5 metres above sea level;
- In December 2003, flooding from the Rhône river rose to a height of 4 metres, necessitating the evacuation of 32,000 people;
- 3,000 square kilometers of land at risk from flooding in the Rhône-Alpes Region are continuously monitored.