WaterWare:   The Kelantan River, Malaysia

Irrigation Model:

The model output is the daily or monthly irrigation water demand in terms of river diversion or extraction/pumping requirements.

The model input includes size and crop pattern of the irrigation object, irrigation technology and transmission, and the local climate as well as groundwater information.

In parallel to the water requirement, the model can generate a simple cost-benefit analysis for the irrigation operation.

The model uses either the FAO CROPWAT approach to determine plant water requirements in the growing season and computes supplementary irrigation water requirements from that, or an alternative model (IRRWD)based on a dynamic concept of plant specific physiological water demand.

The model output is presented in graphical format as time series of the various components of the water budget, which supports the calculation of multiple and overlapping growing seasons for multiple crops.

The model can be structured for hierarchies of irrigation operations, so that it can aggregate the output from numerous individual fields and plots into large irrigation districts.

This possibility9 of a hierarchical representation makes it possible to configure complex irrigation schemes at a high level of detail and realism.

The output, the dynamic supplementary irrigation water demand, can be exported to be used in the overall water resources model (WRM) where the respective irrigation district is represented as a demand node.