Hydraulic structures used to regulate the water level in an artificial reservoir or for its complete emptying.

Spillway, Spillway is a hydraulic engineering structure designed to discharge excess (flood) water from a reservoir and to allow beneficial use of the water to flow downstream. Water is released when there is a risk of the reservoir overflowing due to flooding, heavy rainfall, etc. The exception to this is a spillway, where water is released continuously.

There are 2 types of spillway - controlled and uncontrolled.

Gated spillway - the capacity of the spillway is regulated by special gate mechanisms.

Automatic spillway - the capacity of the spillway is not regulated and depends only on the water level in the reservoir. Water discharge through this type of structure begins automatically when the water level in the reservoir rises above the spillway mouth.