Siak River

The Siak (Sungai Siak) is a river of Riau province, in the east of Sumatra, Indonesia, about 1000 km northwest of the capital Jakarta.^[2] Approximately 370 kilometres in length, the Siak is a blackwater river which owes its brown color to dissolved organic matter (DOM) leached from surrounding, heavily disturbed peat soils; it is heavily polluted, notably by the petroleum industry. It flows through the town of Pekanbaru before emptying into the Strait of Malacca.^[3]

Siak Sungai Siak, Siak rivier
The Siak River flows through the city of Siak.
Location of river mouth Show map of Sumatra Siak River (Indonesia) Show map of Indonesia
Location
Country	Indonesia
Province	Riau
Physical characteristics
Source
• elevation	0 m (0 ft)
Mouth	Malacca Strait
Length	370 km (230 mi)
Basin size	10,423 km2 (4,024 sq mi)[1]
Discharge
• location	Siak Delta, Malacca Strait
• average	(Period of data: 2009–2013)720 m3/s (25,000 cu ft/s)[1]

The Siak River flows through the city of Perawang. Photo taken on the Maredan bridge.

Geography

The river flows in the central area of Sumatra with predominantly tropical rainforest climate (designated as Af in the Köppen-Geiger climate classification).^[4] The annual average temperature in the area is 23 °C. The warmest month is October, when the average temperature is around 25 °C, and the coldest is January, at 22 °C.^[5] The average annual rainfall is 2673 mm. The wettest month is November, with an average of 418 mm rainfall, and the driest is January, with 106 mm rainfall.^[6]

See also

• List of drainage basins of Indonesia
• List of rivers of Indonesia
• List of rivers of Sumatra