The Pride demand model (developed for Victorian farming districts) replicates water requirements for a cropped area using a combination of climate data, crop culture and knowledge of traditional farming practices. These irrigation requirements are used to generate orders within regulated river systems or to drive extractions from unregulated systems. It is governed by factors which determine crop water use - principally the irrigation culture, climate, the characteristics of the soil and the type of irrigation system. In Source, these parameters must be specified in order to define a Pride demand model. Click on the individual parameter in each tab to view its definition in the bottom panel.
Hydroclimatic factors
These are grouped into five categories:
Crop Area
If an annual time series of crop areas is not used, you can specify a single set of crop areas, which applies to the entire model period. Ensure that the order and number of crops are consistent across all steps of model development. The model assumes that the first crop is Annual Pasture. If you do not wish to model Annual Pasture, then you must enter zero hectares of Annual Pasture as the first crop.
Note If crop areas are small, your irrigation water requirements will be less and Source may round the demands to zero.
Climate
You can specify multiple rainfall stations using the Update Rainfall Station Data button (opens Feature Editor 48). To add a rainfall station, right click and choose Add from the contextual menu. You can also rename and delete a station using the contextual menu. Alternatively, use the Add and Delete buttons at the top left side. Load a time series using the right side panel.
Feature Editor 48. Pride demand model, Rainfall Data)
Load a time-series file to specify Evaporation (Feature Editor 47).
Feature Editor 47. Pride demand model, Climate
Click on Update Rainfall Station Data to upload this information via Feature Editor 48.
Limit Curve
This prevents a demand node from using all of its available allocation too early in the season. You can manually enter the available water and its associated limit (both in ML) or import it from a text file.
Return Flows
Refer to Return flows for more information. Note that the percentage of volume supplied can be greater than 100%. This indicates that there is more return flow from the irrigator than diversions due to rainfall runoff.