Siak River

Siak
Sungai Siak
The Siak River flows through the city of Siak.
Location of river mouth
Siak River (Indonesia)
Location
CountryIndonesia
ProvinceRiau
Physical characteristics
Source 
 • elevation0 m (0 ft)
MouthMalacca Strait
Length370 km (230 mi)
Basin size10,423 km2 (4,024 mi2)
Discharge 
 • locationSiak Delta, Malacca Strait
 • average(Period of data: 2009–2013)720 m3/s (25,000 cu ft/s)

The Siak is a river of Riau province, in the east of Sumatra, Indonesia, about 1000 km northwest of the capital Jakarta. 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.