(These parameters apply to the Simplified Coefficient Method. For the Soil Moisture Method, see Soil Moisture, Irrigation; for the MABIA Method, see MABIA, Irrigation; for the Plant Growth Method, see Plant Growth Model Method, Irrigation.)

If you indicate that irrigation is to occur in a Catchment at the time you create the Catchment in the Schematic, the Irrigation tab will appear under the particular Catchment in the Data View. The following irrigation-related variables will require input if the Simplified Coefficient Method is chosen for the Catchment.


Enter 1 if the land class is irrigated. Enter 0 otherwise.

Irrigation Fraction

Irrigation fraction is the percentage of the supplied water available for ET consumption (i.e., irrigation efficiency).

Pump Layer

Groundwater layer or layers (as defined in linked MODFLOW model) from which to pump for irrigation. Specify layer=255 for a cell to have pumping come equally from all layers in that cell. To have withdrawals handled instead as negative recharge, specify layer=0. If pump layer>0, WEAP will add cells to the well file if they are not already there. Use the PumpLayer function to specify fractions to pump from several layers. If blank, will default to 0 (negative recharge).

Depending on the setting in General: Basic Parameters, the pump layer can either be entered once for each catchment and will apply to all the land use branches within that catchment, or can be entered separately for each branch within each catchment.

Note: Pump Layer is only used when linked to MODFLOW.

See also: Simplified Coefficient Method Calculation Algorithm

Entered on: Data View, Branch: Catchments, Category: Irrigation, Tabs: Irrigated, Irrigation Fraction, Pump Layer.