Lake Brunner Dairy Effluent Tool

This tool advises farmers in the Lake Brunner catchment whether or not it is suitable for irrigating dairy effluent onto paddocks. The tool is not predictive because it is based on previous climatic conditions. So farmers will need to check for upcoming rain events prior to irrigating effluent.

Some criteria for use are:

• Irrigation should not be undertaken when the Soil Water Deficit is less than 0.5 mm. Irrigation is more ideal when the SWD is higher.
• The application depth on a given day should not exceed 10 mm. This is so soil capacity is not exceeded and soil/plant nutrient uptake is maximised.
• The model assumes farm dairy effluent is applied to a different paddock each day.
• The instantaneous application rate should be less than the soil saturated hydraulic conductivity. As a rule of thumb a maximum application rate of 5 mm per hour is practical (for no more than 2 hours = 10 mm/day).

For background information on the Lake Brunner Dairy Effluent tool see here.