The effluent collection infrastructure must be designed to handle the volume and consistency of effluent being produced, says DairyNZ.
The system must be designed to handle the peak flow rate of effluent without blocking, overflowing, or leaking. Wash-down system
A water supply is required for wash-down of the dairy shed and, periodically, for washing of other areas such as standoff areas and feed pads.
Wash-water can form a large proportion of the total volume of FDE produced. Thus, it is important to determine the final specifications of the wash-water system prior to designing the rest of the collection and conveyance system.
Wash-down water is usually supplied from clean bore or surface water.
Consider any available alternative systems to minimise water use. For example, consider the use of recycled water, or harvested stormwater, for washing areas that do not require high quality water (eg feed pads, stand-off areas or animal housing areas).
Always check local regulatory requirements prior to designing systems that use recycled water.
In addition to the general hydraulic design requirements, the collection infrastructure must be able to:
- handle the peak flow rate of FDE into the system
- collect material from all enclosed areas subjected to animal FDE
- avoid potential contamination of groundwater and surface water bodies
- comply with all regulatory requirements.
Initial collection may be by a number of different methods. Common effluent collection methods include:
- hose wash
- flood wash
- Scraping by chain in a groove in the floor, rubber backing gates or scraper attached to a farm vehicle.