The Cooum River, or simply Koovam, is one of the shortest classified rivers draining into the Bay of Bengal. This river is about 72 km (45 mi) in length, flowing 32 km (20 mi) in the city of Chennai and the rest in rural part. The river is highly polluted in the urban area (Chennai). Along with the Adyar River running parallel to the south and the Kosasthalaiyar River, the river trifurcates the city of Chennai and separates Northern Chennai from Central Chennai. It is also sometimes known as Thiruvallikenni river