Box 4 · Off the sewer
On-site sewage systems and Central Coast Council
Where a Central Coast property cannot connect to Council’s sewerage system, its waste is managed on the property, and Council asks for an application before a system is installed or altered, and registration with an approval to operate for every system. When an existing system is altered, works to the internal plumbing and drainage also go through Council’s usual inspection application.
General information, not legal or technical advice. Central Coast Council’s on-site sewage management page holds its current applications and guidelines.
Off the sewer: what Council means by an on-site system
Council describes on-site sewage management systems as the ones installed where a property has no connection available to its sewerage system, so the waste from the home has to be dealt with on the site itself. Its page gives six examples: a septic tank draining to an absorption trench or evapotranspiration bed, a septic tank that is pumped out, an aerated wastewater treatment system, a sand or fabric filter, a wet composting system and a composting toilet.
Council is also the body that collects sewage on the Central Coast: its water supply page lists collecting sewage, with its transport, treatment and discharge, among the services it delivers across the local government area. An on-site system is what a property relies on where a connection to that system is not available.
Three applications, three moments
Council’s page sorts its requirements by what is happening to the system. Each one has its own paperwork.
Installing a new system, or altering one
Council asks for an Application to install or alter an On-site Sewage Management System, whether the system is new or an existing one is being changed.
Running a system that is already there
Every on-site sewage management system has to be registered with Council, and an approval to operate is required. That approval comes through Council’s Application for an approval to operate.
Altering a system: the plumbing inside
Under altering an existing system, Council adds that works to the internal plumbing and drainage need a Plumbing and Drainage Inspection application, with its fees, the same application that starts Council’s five inspection steps.
Council places registration and the approval to operate under operating an existing system, so they concern anyone who owns a property with a system running, not only someone planning new work.
An old septic tank
Replacing an old septic system can mean demolishing the old tank. Council’s page says that demolishing an old tank must follow the procedures in NSW Department of Health Advisory Note 3. This guide does not restate those procedures: Council’s page links the advisory note, and the note sets them out.
Which licence covers the work
In NSW a licence or certificate is needed for any plumbing, draining or gasfitting work, “regardless of the cost of the work or whether the work is residential, commercial or industrial.” Building Commission NSW’s definitions of the licence categories name on-site systems directly:
| Category | What it says about on-site systems |
|---|---|
| Sewerage work (part of plumbing) | Covers work on sewerage service pipes, fittings and fixtures that connect, or are meant to connect, “with a sewer or onsite wastewater management systems”. |
| Draining work | “This includes work on a house drain connected to an onsite wastewater management system.” |
| Water plumbing | Includes work on pipes and fittings in a building where any part of the sewerage service connects to an on-site wastewater management system, whether or not they connect to a water main. |
So the work on and around an on-site system sits inside the same licence categories as work on a sewered property. The licences guide matches each Council step to the licence it names.
Drainage diagrams off the network
When a plumber does sanitary drainage work on the Central Coast, Council’s inspection steps have them give Council and the customer a drainage diagram within two days of finishing. For areas beyond the Sydney Water and Hunter Water networks, Building Commission NSW says the local plumbing regulator may be able to supply sewer service diagrams. For the Central Coast, that regulator is Central Coast Council, as the guide to who regulates explains.
The order of things on a property off the sewer
Put together, a property with an on-site system meets Council at up to three points: when a system goes in or is altered, through the application to install or alter; for as long as it runs, through registration and the approval to operate; and when an existing system is altered and its internal plumbing and drainage is worked on, through the inspection application and the steps that follow it. Each of those is lodged with Council, and the plumbing and drainage work itself needs a licence, as the table above shows.