Draft Performance Standards for Septic Tanks and other Domestic Waste Water Treatment Systems

The draft performance standards for septic tanks and other domestic waste water treatment systems were published on 1 March 2012.

The draft standards set out the responsibilities of owners of septic tanks and other systems may be summarised as follows:

  • Know where your tank/treatment system is located.
  • Visually examine the tank/treatment system and percolation area every year.
  • Inlets/outlets/distribution pipework are to be kept clear of any adverse material or blockages.
  • Man-hole covers, manholes, distribution box, T-pieces, pipes, tanks are to be in good working order, undamaged and sealed where appropriate.
  • The distribution-box/pump chamber should be watertight and the distribution box should be level and allow for even distribution.
  • Mechanical or electrical equipment (e.g. pumps, aerators, alarms etc.) should be fit for purpose and operational.
  • Aeration vent pipes should be dry and free from obstructions.
  • The percolation area should be free from disturbance from vehicles, heavy animals, sports activities or other activities likely to break the sod on the surface.
  • Only domestic waste water is treated in the tank/treatment system.
  • Roof water and surface water runoff is not allowed to enter the waste water treatment system.
  • The septic tank capacity and configuration should be sufficient to allow for settlement and retention of solids in accordance with general occupancy levels.
  • A domestic waste water treatment system should be operated and maintained by the owner so as to ensure that it is not discharging from a place or part of the system where it is not designed or intended to discharge (ie. ensure there is no seeping, leaking or other escape of wastewater).
  • The effluent discharge pipe from the treatment system should not discharge directly to the surface of the ground or result in “ponding” on the surface of the ground.
  • A treatment system should not directly discharge into surface waters except where this is licensed under Section 4 of the Local Government (Water Pollution) Act 1977.
  • Desludge the tank/treatment system when necessary using an authorised waste collector.
  • Operate and maintain the system as per the manufacturer’s manual.

As part of the inspection system to be introduced, the Draft Performance Standard indicates that where a treatment system is found to be operating in a manner which contravenes the operation and maintenance regulations, practical and pragmatic solutions will be identified to bring the treatment system into compliance in the most efficient manner, having regard to the circumstances and to the level of the risk to human health and the environment.

However, if a system is inspected and there is no evidence of a risk to human health or the environment, no remedial action will be required for the treatment system (including the percolation area), irrespective of the type or age of the system.

No Treatment Quality Standards have been presented as pert of the Draft Performance Standard.