Empty effluent ponds before winter sets in

As winter approaches, now is the time to ensure the farm’s effluent ponds are emptied before the possible wet winter months.

Utilising the nutrients contained in the dairy effluent can provide a boost to autumn pasture growth.

All dairy farmers are required by legislation to keep dairy effluent on-farm and out of waterways.

Ensuring your ponds are empty before winter will assist you to manage your effluent system with more ease over the wet months.

Effluent systems are generally designed to have the storage ponds empty going into the wetter months of the year.

These are the months when rainfall exceeds evaporation making conditions unsuitable for effluent application due to increased risk of nutrient run off and waterlogging.

In West and South Gippsland this is generally eight to nine months starting in March and finishing October or November, depending on your location.

For drier areas of Gippsland it will be for five to seven months starting in May and finishing in October or November.

Effluent is a valuable source of nutrients containing large amounts of nitrogen and potassium along with smaller concentrations of a number of other nutrients.

Ideally effluent should be tested to understand the amount of nutrient being applied.

Average figures are available, however, there is significant variation in nutrient concentration between farms and seasons.

This is due to a number of factors including herd size, milk production, amount of time spent on yards, water use in the dairy, catchment area contributing rainfall to the system and the length of time which has passed since the ponds were last cleaned out.

The nutrient contribution from the applied effluent should be factored into the farm nutrient budget and fertiliser application should be altered accordingly on paddocks where effluent has been applied.

For best response rates, effluent should be applied to actively growing pastures or crops.

Be mindful that effluent often has a high salt content making it unsuitable for application on germinating seedlings.

Post application pastures should not be grazed for at least three weeks to allow the plants to utilise the available nitrogen applied and reduce the potential risk of pathogens the effluent may contain.

If possible, apply effluent to areas of the farm with lower soil fertility.

Regularly rotate the areas where effluent is applied and undertake regular soil testing to monitor nutrient levels and avoid excessive accumulation of nutrients.

For more information visit agriculture.vic.gov.au/agriculture/dairy/managing-effluent or contact your local dairy extension officer at Ellinbank (5624 2222).