[2] The river flows in the southern area of Sumatra which has a predominantly tropical rainforest climate (designated as Af in the Köppen–Geiger climate classification).

[3] The annual average temperature in the area is 24 °C.

The warmest month is October, with the average temperature of 26 °C, and the coldest is January, at 22 °C.

[4] The average annual rainfall is 2,902 mm.

The wettest month is November, with an average of 435 mm rainfall, and the driest is August, with 83 mm rainfall.