Chute spillways convey flood releases down steep slopes at high velocities. Flow entering the chute transitions from subcritical to supercritical, developing a growing boundary layer along the channel bed. The point where the turbulent boundary layer intersects the free water surface is the Inception Point of Aeration. Beyond this point, self-aeration occurs as air is entrained into the flow stream. Aerated mixture depth $(y_{ae})$ and bulked velocity $(v_{ae})$ are computed using the mean air concentration $(C_{mean}):$ $y_{ae} = \frac{y_w}{1 - C_{mean}} \quad \text{and} \quad v_{ae} = \frac{Q}{A \cdot (1 - C_{mean})}$ Where $y_w$ is clear-water depth. Aeration offsets negative pressure zones along the chute floor, preventing destructive cavitation erosion when local flow velocities exceed $20\text{ m/s}.$ High-head spillways across steep Himalayan valleys frequently experience intense cavitation damage during extended monsoon discharges. Modern spillway designs in India inco...