Radial gates are movable control structures. The water flows under the gate. The core element of a radial gate is a wall with the shape of a segment of a circle. The gate causes backwater in the flume.
Radial gates are often used in combination with a fixed control structure, e.g. a broad-crested weir. These combinations are typical for barrages. With them the discharge in the open channel can be adjusted and controlled according to the needs.
The gate opening of the radial gate HM 163.40 and therefore the discharge under the gate can be manually adjusted.