Ummm, you don't have to wait till 2050:
Vietnam hit by worst drought in nearly a centuryMonths of below-average rainfall have conspired to produce the worst drought in Vietnam in the best part of 100 years. It has been reported that the Mekong River is at its lowest level since 1926.
The ongoing El Nino weather pattern is thought to be the main cause of the lack of rainfall affecting the country.
Vietnam is not alone in suffering drought. Neighbouring Cambodia, and Laos, as well as Thailand and Myanmar, have been experiencing water shortages as a result of the weather phenomenon.
http://www.aljazeera.com/news/2016/03/v ... 48729.html
Thailand hit by its worst drought in decadesThailand is in the grip of its worst drought for more than 20 years, with water levels in the country’s biggest dams lower than 10 percent.
The current drought has hit the north hardest, with 22 of Thailand’s 76 provinces affected.
Agriculture has been severely affected, and there are genuine fears that taps could run dry within a matter of weeks. Several major reservoirs in the country are below 50 percent of their water capacity.
http://www.aljazeera.com/news/2016/03/t ... 23735.html(Thanks, as often, to COBob at rs's blog for these links and extracts.)
But, yeah, these kinds of extreme drought events will certainly be getting worse and more seveer in the coming years and decades.