Stepped spillway

During Antiquity, the stepped-chute design was used for dam spillways, storm waterways, and in town water supply channels.

Most of these early structures were built around the Mediterranean Sea, and the expertise on stepped spillway design was spread successively by the Romans, Muslims, and Spaniards.

During the first half of the 20th century, the stepped cascade design fell out of fashion, partly because of the maintenance costs but also because of the development of hydraulic jump stilling basins.

Some strong hydrodynamic fluctuations, splashing, and spray near the free surface constitute the main features of this flow regime.

[4] These recirculation eddies are maintained by the transmission of shear stress from the mainstream, and they contribute significantly to the energy dissipation down the stepped spillway.