This is a popular activity in Thailand, and you will find many locations that offer this. Popular places include Chiang Mai, Pai, and Chumpon. The rapids can vary from anywhere from level 1 to 5. For the ultimate rafting experience try out a rafting journey on a lush tropical jungle, there is bound to be wild animals roaming about as you make a splash along the rapids. You can go for 6 hours, 2 hours or perhaps even an overnight trip. Camping is provided with special tents made out of bamboo. This sort of adventure is offered by companies, especially in the North of Thailand.
Something to consider when picking the location for white water rafting is the level of the rapids, and in some areas, it may not be available all year round either.