Water
Water use, sustainability, and efficiency by choosing quality systems and materials, and providing environmentally friendly solutions.
Design checklist
Use this step-by-step to guide design of an on-site wastewater treatment system.
These are the stages of an on-site wastewater treatment system design process as set out in AS/NZS 1547:2012 On-site domestic-wastewater management.
Stage 1: Feasibility study
Determine requirements by preliminary:
- discussion with system suppliers
- identification of site conditions
- discussion with regulatory authorities.
Stage 2: Evaluation and investigation
Includes soil evaluation for permeability and drainage capability, and site investigation to identify:
- gradients
- site boundaries
- building positions
- runoff
- stability
- groundwater conditions
- location of nearby wells, springs and watercourses
- vegetation
- climatic conditions.
Stage 3: Selection system
Consider the:
- number of occupants
- site conditions
- local authority regulatory requirements.
Stage 4: Design distribution system
Must include:
- uniform, effective and continuous distribution
- an area that can be controlled and maintained.
Stage 5: Approval/consents
Obtain as required from regulatory authorities for:
- location
- system specification
- operation
- maintenance
- monitoring.
Stage 6: Installation
In accordance with:
- approved design drawings and specification
- manufacturer’s instructions
- certification as required by the regulatory authority.
Stage 7: Operation and maintenance
Includes:
- providing an operations and maintenance manual
- keeping records of all servicing/inspections/remedial actions
- carrying out regular inspections/cleaning
- having a service and maintenance manual with the supplier (for AWTS/ASTS)
- maintaining the land application area.
Updated: 26 July 2024