Sathanur Reservoir is formed by Sathanur dam, one of the major dams constructed across the Pennaiyar River. Sathanur Dam is constructed across the Thenpennai River in Thandarampet taluk among Chennakesava Hills. The dam can be reached by road 30 km (19 mi) from Thiruvannamalai Town. It was constructed in 1958. There is also a large crocodile farm and a fish grotto. Parks are maintained inside the dam for tourists to visit and the gardens have been used by the film industry.
The reservoir has a capacity of 7,321,000,000 cu ft (207,300,000 m3) with a full level of 119 ft (36 m). An area of 7,185 ha (17,750 acres) of land is benefited by the left bank canal and 100 ha (250 acres) of land is benefited by the right bank canal in Thandrampet and Thiruvannamalai blocks.