Manjalar originates from Palani hills and runs towards east and joins the Vaigai River near Koottathu. There are 9 anicuta and 9 tanks in this sub basin. It receives an annual rainfall of 775 mm. The total sub basin area is 470 km². The total ayacut of the sub basin is 2155.53 Ha. Across the river at around 10 km from Batlagundu bus stand in Dindigul District, Manjalar Dam has been constructed for irrigation purposes. Manjalar Dam is at the end of Manjalar Road about 5.5 kilometres (3.4 mi) north from SH-36 at Devadanapatti town beginning along Kamatchi Amman temple road. Manjalar dam can be viewed from the Kodai Ghat road, en route to Kodaikanal, about 19km from Vattalkundu.