The Meenachil River or Meenachilaar, also known as Kavanar, Valanjar, is a river in Kerala. It is one of the most treacherous rivers in Kerala due to its flash floods, heavy undercurrents and woods and debris it carries from the mountains. It flows through the heart of Kottayam district, Kerala state in southern India. 78km long, originates in the Western Ghats main tributaries are Theekoy aaru from Vagamon hills, Poonjar Aaru and Chittar, flowing westward through the city of Kottayam and other towns like Poonjar, Teekoy, Erattupetta, Bharananganam, Pala, Mutholy, Cherpunkal, Kidangoor and Kumarakom before emptying into the Vembanad Lake on the shore of the Indian Ocean.

Kottayam is a city in the Indian state of Kerala, flanked by the Western Ghats on the east and the Vembanad Lake and paddy fields of Kuttanad on the west. It is the district headquarters of Kottayam district, located in south-west Kerala. Kottayam is located in the basin of the Meenachil River at an average elevation of 3 metres (9.8 ft) above sea level. It has a moderate climate. It is located approximately 155 kilometres (96 mi) north of the state capital Thiruvananthapuram.