Irrigator operates on a daily basis generating demands and extracting water to meet these demands via the water user and supply nodes. Irrigator maintains a daily water balance for each cropping area during its planting season to calculate the daily soil water deficit and an irrigation requirement. The irrigation requirements are used by the Water User to generate orders and opportunistic requests and to subsequently place orders and requests and to extract water from a water source.The model can be applied in both regulated and unregulated systems.
Configuring generic crop settings
Before configuring an Irrigator Demand Model on a Water User node, you must specify crop factors for the entire scenario using Crop factors defined in this way are accessible for each water user node. More details regarding this can be found under IQQM CropMod2 Demand Model (check/change link when migrated to permanent site)
District Configuration
This describes a number of parameters that can be set at an irrigation district level. The maximum irrigated area is a nominal area that can be set because the total area planted within a water year is not limited other than through the planted area. A warning is then recorded runtime if the planted area exceeds the maximum irrigated area of the district. Soil moisture capacity is specified at the district level and this is assumed constant for all crops in the district. If user has specified irrigation season, orders and requests are only generated within the season. Both irrigation and opportunist requirements can be limited to within an irrigation season.
Temporary Screenshots to be updated with production release 3.3.0
Feature Editor - Irrigator Demand Model (District Configuration)
Supply Escape
The district requirement is adjusted to allow for any district delivery supply escapes and losses associated with delivering water to the district. The volume removed before getting to the crop 
is called the escape volume. The escape volume can either be lost from the system or returned back to the water user as a return flow. This is optional in the demand model configuration and can be added by right clicking Irrigator and selecting Supply Escape. It is expressed as a percentage.
Return Efficiency
Returned water is surplus drainage water from irrigation or from rainfall runoff. This water can be redirected into the on farm storage or otherwise can be returned to the river via a confluence node. This is optional in the demand model configuration and can be added by right clicking the Irrigator (menu item) and selecting Return Efficiency. It is expressed as a percentage
Target Modifier
Irrigation modifiers are included into Source to allow a simple mechanism to reduce irrigation intensity for recurring periods of time.
Climate Configuration
There are four parameters that can be defined for climatic data
Feature Editor - Irrigator Demand Model (Climatic Parameters)
Crop Configuration
This is used to define parameters specifically related to the crop to be planted. Add a new crop by right clicking Irrigator and selecting Add Crop Type. The Source Scientific Reference Guide should be consulted for greater detail regarding parameters for the following sections.
Feature Editor - Irrigator (General Crop Configuration and Soil Configuration)
Fallow Crop
Areas that are not being cropped are referred to as fallow. Fallow area occurs between cropping seasons or during the irrigation season if the maximum developed area is not planted. The fallow cropping area does not order or receive irrigation water. Although the depth of rootzone is also specified for fallow, the fallow has no rootzone. This is treated as the depth of soil from which evaporation can occur.
Soil Configuration
Crop specific soil factors can be defined on the same page as General Configuration see Feature Editor - Irrigator (General Crop Configuration and Soil Configuration). Soil moisture capacity is specified at the district level and this is assumed constant for all crops in the district. The Depth of the Root Zone, Depletion Factor and Initial Depletion are specified for each crop.
Planting Decision
Planting decisions are represented as a trigger in the Irrigator Demand Model and include a decision type, plant date, optional harvest date, planted area definition and an under irrigation factor.The number and size of cropped areas changes over time in response to planting decision triggers and available water.
Irrigator allows crop based planting decisions which better align with economic modelling than earlier crop demand models. If the planted area is defined using the expression editor, then other factors such as economics can be considered.
Feature Editor - Irrigator (Planting Decision Trigger)
Soil Depletion
The amount of water in the rootzone is defined in terms of rootzone depletion. Rootzone depletion describes the soil water deficit of the rootzone, relative to field capacity. The target depletion is a user specified input and can be specified as either a pattern or as an expression.
Two target depletions can be specified
1) A Regulated Target. This is the target at which Irrigators water and attempts to maintain soil depletion.
2) An Opportunistic Target. This target is used to generate opportunistic requests.
Economics
A simple, linear crop water production function is used to predict the reduction in crop yield resulting from water stress. Irrigator records the relative yield as a daily time series. This functionality is still in the prototype stage. For more information consult the Irrigator Demand Model page of the Source Scientific Reference Guide.
More information on how Economics works to be included as functionality develops in software.
Feature Editor - Irrigator (Crop Economics)
Crop Runoff
This is to specify the proportion of applied irrigation water that becomes runoff, as well as the runoff that can be harvested and returned
Crop Deep Percolation
This is to specify the percentage of applied irrigation and rainfall that becomes deep percolation and drains below the rootzone.