Climate hazard and extreme events

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4.1.4 Climate hazard and extreme events

During the monsoon period, heavy rainfall trigger every year flooding of various intensity. The carriage way of the main river and associated drainage network is not sufficient to cope with the sudden amount of water. The water level thereby rises rapidly, leading to flooding and further erosion. Recently, in July 2000 massive floods, destroying the surrounding fields, affecting livelihood and leading to business interruption, overwhelmed the city. In 2006, flash floods occurred and affected the built-up environment as well as the utility and facility networks within the city. Transportation system was blocked and tourist activities ceased for various days. Loss of crop and economic breakdown led to migration wave to Bangkok. Water run-off is constantly increasing due to inadequate land-use planning coupled with increasing climate variability. Landslide and mudslide are substantial issues Chiang Rai has to face over the past decade. The topography of the zone associated with heavy rainfalls and unplanned human settlements, leads to increase the landslide risk and therefore the correlated damages on livelihoods, infrastructures and property. In fact, each year landslide occurs in the zone. For instance, in 2005, seven events have been reported in Chiang Rai province, affecting a total area of 800 square meters; and in 2007, four landslide events occurred, affecting 300 square meters. Tropical storms are highly frequent in Chiang Rai. Since the beginning of the eighties, the cyclone frequency tends to be accelerated. Strong winds, comprised between 63 kmh and 118 kmh and heavy rainfalls are associated to cyclone period. In recent times several ice rains and gale has been common phenomena. Drought is also of main concern in the province. In April 2008, a period of extreme drought hit the province. The Mekong River was very shallow, impeding the boat tour to work. According to TNA, 314,000 families in 18 districts have been hardly affected by water shortages. The lack of irrigation facilities for agriculture has led to the lost of the crops. In fact, more than 68,000 rai 27,700 acres of agricultural lands have been damaged. The provincial authorities have declared the 18 districts of Chiang Rai as a drought ravaged area.

4.2 Udon Thani