Parambikulam Tiger Reserve in Palakkad has three man-made reservoirs - Parambikulam, Thunakadavu, and Peruvaripallam. The Thuvaiar waterfalls empty into one of the reservoirs. The Karappara river and Kuriarkutty river also drains in this area.
Also, do not miss out on these
Reservoir at Parambikulam | Parambikulam Tiger Reserve