On-site sewage management

An On-Site Sewage Management System (OSSM) is part of the plumbing system on an unsewered property, and normally includes a tank for treating raw sewage and a disposal system. Types of OSSM systems include:

• septic tanks
• aerated wastewater treatment systems (AWTS)
• greywater treatment systems
• wet and dry composting toilets
• alternative systems 

These systems include sewage management facilities that treat domestic sewage from up to 10 persons with an average daily flow of less than 2000 litres.

There may be an issue with the system if any of the following are occurring.

• Water inside the house don’t drain away freely
• There is excessive noise coming from the system
• There is a sewage odour coming from the system or disposal area
• There is pooling of liquid around the system or disposal area
• The system is not protected from stormwater run-off
• There is excessive or a large amount of vegetation around the system and/or disposal area
• For AWTS systems, they have not been serviced regularly (quarterly) or maintained.

If using subsurface disposal 

• Cattle/horses are allowed in the disposal area
• There is visible damage to the trenches

If using surface irrigation

• Irrigation sprinklers aren’t working
• There are missing sprinklers
• Spray is not contained within a specific area with limited drift or allowed to go over property boundaries
• Inappropriate hoses and plumbing fittings being used (fittings should be non-domestic, low pressure, low volume)