The first community I passed by live on boats at the river mouth intersection of Tonle Sap and Tonle Thom.
Further down on the other side of the river, at Lower Mekong River, people live at wooden houses, some on the ground and some on the water.



Source: axn-asia.com
Sungai Kampar which is located at Perak, Malaysia is a good place for this adventure. The river here is mostly of Whitewater Class 1 and Class 2 category, with some occasional Class 3 rapids here and there. Located somewhere along the main North-South trunk road near Kampar town, I don't remember seeing any clear signage directing people to this place.
We have conquered Sungai Kampar!