Hi, you need to know the ...
Published by Muhammad Alfalah Fauzi, CFD Engineer Intern at Institut für Wasserbau und Technische Hydromechanik (IWD) - TU Dresden
Hi, you need to know the geomterical of the weir as well (upstream and downstream slope, height, length).
You can also use hydraulic jumps formula to simplify calculation for an approach. The parameter you can acquire is the water depth and weir height which resulting those gradient flow regimes.