[3] The river flows in the southeast area of Borneo island with predominantly tropical rainforest climate (designated as Af in the Köppen-Geiger climate classification).

The warmest month is June, when the average temperature is around 26 °C, and the coldest is January, at 22 °C.

[6] The Tabalong River provides a large swamp land, which can be used to grow rice during the dry season.

However, during the wet season, the discharge of the river and its tributaries increases so high, that it often threatened the harvest and caused flooding in the nearby villages.

[9] The abundance of water during the wet season is actually useful to fill up the pools for fishery.