The Palar is a perennial river which originates in Kolar in Karnataka and flows through Vellore and Kanchipuram district of Tamil Nadu.The main tributaries of the Pallar are the Ponnai and the Cheyyar rivers.

River Cheyyar flows through Chengam Taluk of Tiruvannamalai district and is an important seasonal river of the region. It receives rain during the Northeast and Southwest monsoon periods. Cheyyar River passes through several villages of Chengam Taluka, and is the major source of irrigation. The Taluka has different types of soil, such as black, red loam and sandy loam. Major crops raised in the Taluk are paddy and groundnut. Magaral lies on the northern banks of Cheyyar River. The Vedapureeswarar temple is located on the banks of the Cheyyar River.