Overseer Limited are not currently aware of any peer reviewed independent scientific data to enable "effluent bladders" to be added to the Overseer model.
In the absence of any current science, Overseer engaged with the DairyNZ Effluent Advisory Group.
The currently recommended work around is to model effluent bladders as Holding ponds - either with or without solid separation depending on the nature of the whole system.
- Holding Pond – there is a facility to store effluent on farm and you have options on when you can apply liquid effluent. You are required to describe what happens with the pond solids.
- Holding Pond – Solids are separated* - there is a facility to store effluent on farm and you have options on when you can apply liquid effluent, solids are separated before they enter the holding pond. When this management option is selected you are then required to enter what happens with solids separated from effluent before transfer to pond and what happens to the pond sludge.
*This approach assumes that the separation ratio is the same for the different types of separation systems, such as mechanical separation, seepage walls, or settling ditches.
We hope that the manufacturers of these storage systems will engage with the science community to enable the collection of sufficient independent data to allow the inclusion of effluent bladders into the Overseer model.