Point estimates of the following are required for manual data entry: Root Zone Drainage rate (ML) Area of application (ha) Average Annual Rainfall (mm) Distance fom River/Floodplain (m) Depth to Aquifer (m) Thickness of Aquitard (clay) (m) Aquifer diffusivity (or Specific Yield and Transmissivity) Aquifer salinity at the discharge point (mg/L) Floodplain attenuation factor* River connectivity factor* Assessment Reach# * For no floodplain attenuation factor = 1, for full river connectivity with aquifer factor = 1 # Assessment Reach is selected from a drop down list and is required for use of the BIGMOD Ready Reckoner ex MDBC

Output from each stage of the modelling process is provided on separate worksheets in both tabular and graphical formats.

SIMRAT has been extensively tested and compared with observed data and other more detailed model outputs.

Independent peer review has been provided by Aquaterra Pty Ltd.

Algorithms have been reviewed extensively by CSIRO Land and Water and non-ideal situations (where the model assumptions begin to break down) have been identified.

Some workarounds are provided for non-ideal situations in SIMRAT-XL (see all workbooks titled XXX....).

SIMRAT also has the following disadvantages:

• Detailed modelling of individual sites is not undertaken. For final design of new irrigation schemes local models are recommended.
• Simplifying assumptions may be inappropriate in some areas.