The Meenachil River is formed by several streams originating from the Western Ghats. The general elevation ranges from 77 m to 1156 m in the highlands and less than 2 m in the lowlands and 8 to 68 m in the midlands. The Meenachil has a watershed area of 1208.11 km². The river has a total annual yield of 2,349 million cubic metre and an annual utilizable yield of 1110 million cubic metre. The river has 38 tributaries including major and minor ones. The river has 47 sub watersheds and 114 micro watersheds.