Different types of energy dissipators may be used along with a spillway, alone or in combination of more than one, depending upon the energy to be dissipated and erosion control required downstream of a dam. Broadly, the energy dissipators are classified under two categories – Stilling basins or Bucket Type. Each of these are further sub- categorized as given below.
Stilling basin type energy dissipators :
They may fundamentally be divided into two types.
Hydraulic jump type stilling basins
Horizontal apron type (Figure 38)
Sloping apron type (Figure 39)
Jet diffusion type stilling basins
Jet diffusion stilling basins (Fig.40)
Interacting jet dissipators (Fig. 41)
Free jet stilling basins (Figure 42)
Hump stilling basins (Figure 43)
Impact stilling basins (Figure 44)