hey,can you pls elaborate how to measure the headflow using simplified coefficient method.

Aiman,

There is a subchapter called Using the Simplified Coefficient Method under the Hydrology chapter of the WEAP Tutorial, https://www.weap21.org/tutorial/, which can guide you in setting up this method.

Essentially, your catchment object has climate inputs of precipitation and ET reference (which is the amount of reference ET based on climate effects) and then an input of Kc for each land use type (representing the ET associated with the land cover type). Any precipitation that does not evaporate is assumed to runoff and generate streamflow. Note that this method does not consider effects of antecedent soil moisture, which the Soil Moisture Method provides more accurately.

Hope this helps!
-Doug