In hydrology, a Venturi flume is a device used for measuring the rate of flow of a liquid in situations with large flow rates, such as a river.
[1] It is based on the Venturi effect, for which it is named.
Cone in Fort Collins, Colorado.
By the Venturi effect, this causes a drop in the fluid pressure at the center of the constriction.
By comparing the fluid pressure at the center of the flume with that earlier in the device, the rate of flow can be measured.