Waste Water Treatment:

AgFirst Engineering has extensive involvement in the design of rural school and marae waste water treatment and disposal systems.

The treatment systems generally involve large septic tank treatment and subsurface dewatering systems.

For rural situations the simpler the wastewater treatment and dewatering system is, while maintaining the required discharge quality, the better.

If a passive treatment system can be designed, utilising gravity, this is the ideal situation. This overcomes the problems associated with power outages, pump, air blower and filter maintenance.


Waste Water Treatment Design consists of

  • Site soil evaluation including, soil permeability, site stability, seasonal water table levels, soil structural strength and drainage impediments etc.
  • Annual wastewater volume profile.
  • Treatment system design.
  • Treated waste water discharge system.