The plinth or toe slab connects the face slab. The plinth design, dimentions, stability, construction treatment are most important. Dimention of the plinth have been selected based on precedent and generally vary with reservoir head and with coundation condition. (ICOLD 141)

The diameter of the plinth of Dhap dam is 10m (7m Internal 40cm thickness and 3m External 30cm thickness) with reinforced.