Discharge depends upon the differences of head between distributary and the water course. Example – open sluice and drowned/submerged pipe outlet
Semi-Modular Outlets
Discharge is independent of the water course so long as minimum working head is available. Example- Pipe Outlet, Venturi Flume, Open flume and Orifice semi-module
Modular outlets
Discharge is constant and fixed within the limits irrespective of the fluctuations of the water levels. Example – Gibb’s Module