Drainage inspections

The VBA conducts random inspections of work to ensure it complies with the relevant standards, regulations and codes.

This involves the construction, installation or alteration of below-ground sanitary drains and associated gullies, regardless of the cost of the work, to ensure it complies with the relevant standards, regulations and codes.

Drainage inspection process

If you're a licensed plumbing practitioner carrying out below-ground sanitary drainage work, it is your responsibility to book an inspection for all below ground sanitary drainage pipe sections that have been laid, before the work is backfilled.

You'll be asked to nominate a time for the inspection when booking. At the booked time, you'll need to be on-site with a copy of the Conditions of Consent to Connect and the As-laid Drainage Plan.

You'll also need to ensure that the excavation is open and that the drain is under an air test or water test (when reticulated recycled water is available at the site).

Not all bookings will result in an actual inspection. If an auditor does not attend your site within 30 minutes from the booked inspection time, you are no longer required to keep the work open for inspection and may proceed with backfilling.

Book a drainage inspection

Inspections can be booked from 7am to 4pm on the day prior to inspection online through eToolbox.

Remember, you will still need to lodge the compliance certificate once you have completed the job.

Failure to attend an inspection at the booked time and site may attract a substantial fine.

If you have a valid reason to cancel a below-ground sanitary drainage inspection, you can do so through eToolbox before 4pm on the day prior to inspection or by calling 1300 815 127.

Urgent repairs to below-ground sanitary drains

If you are called out to perform emergency below-ground sanitary drainage work, it may be necessary to backfill the drain before arranging an inspection. Circumstances where this would be acceptable include if work is performed outside normal working hours, or if the drain excavation is on a pathway or driveway that could impact on the safety of others.

However, you must immediately book an inspection for the next available booking day, and complete and lodge an urgent repair notice with the relevant water authority. You must also contact the VBA to report that emergency sanitary drainage work has taken place.

If your job is selected for inspection, and the auditor agrees that it was an emergency job, then a surface inspection will take place.

Frequently asked questions

What work requires a below-ground sanitary drainage inspection?

Below-ground drainage work that requires a drainage inspection includes:

  • connections of previously on-site sewerage treatment systems (primarily septic tanks) to reticulated sewerage systems
  • new below ground sanitary drainage connections to the relevant sewerage authority's sewer connection point
  • sewerage connections on redeveloped sites to the relevant sewerage authority's sewer connection point
  • all pre-slab drainage work and alterations on both new and renovation work
  • alterations to existing below ground sanitary drains
  • cut and seals of disused below ground sanitary drains or branches
  • urgent repairs to existing below ground sanitary drains (either where drain sections are replaced or where below ground sanitary drains are opened up for maintenance, other than the removal of a PVC inspection opening cap or cast iron inspection opening insert).

What work does not require a below ground sanitary drainage inspection?

  • below ground stormwater drainage work
  • property service drains connected to the inlet of a septic tank or aerated wastewater treatment systems (AWTS's).

Licensed plumbers or drainers are not required to book inspections for below ground sanitary drains that are connected to the inlet of a septic tank or AWTS. This is the responsibility of local councils to issue permits to install septic tanks and or AWTS's as opposed to water authorities who supply the plumbing industry consent numbers needed to book a below ground sanitary drainage inspection.

However, septic tank or AWTS installations will require a preliminary inspection and a final inspection prior to backfilling by the council's Environmental Health Officer to ensure the installation complies with AS/NZS 1547 On-site domestic wastewater management, the Code of Practice Onsite Wastewater Management and the provisions of the permit to install. 

The council may need a minimum notice time to book a final inspection. Once the installation has been inspected and approved, the council will issue a "permit to use" and the system can be commissioned to the manufacturer's installation instructions.

What aspects of the job will be inspected?

The inspections are carried out when the below-ground sanitary drainage work is complete but before the drain is backfilled. The inspection parameters normally include an examination of:

  • drain ventilation
  • property sewer connection point
  • boundary trap (BT) or Inspection shaft (IS)
  • approved materials
  • bedding and bedding materials - gradient
  • minimum cover requirements - backfill material
  • infiltration protection - integrity of cut and seal
  • surcharge protection (Overflow Relief Gully (ORG) or Reflux Valve (RV))
  • drains under buildings that only serve fixtures within that building.

What are the minimum requirements for redeveloped sites?

Where a site is to be redeveloped, all existing cement jointed vitrified clay drains are to be renewed in their entirety within the developed property's boundaries, to the property sewer connection point.

Where an existing BT or IS is found to have been replaced in either cast iron or PVC, is fit for purpose and in proper working order, the BT or IS may remain but is to be tested.

RVs, BTs and ISs must be sited clear of easements but within the property boundary. Where a building is constructed abutting an easement or where the building line is on the property boundary the BT or IS must be recessed into an external wall with permanent access for maintenance and rodding of the shaft. Alternatively the shaft may be installed in an easement or right of way but only after the permission of the relevant authorities has been obtained.

What are the minimum requirements when a combined or shared property service drain is not able to be diverted around a proposed building or structure?

The minimum requirements are:

  • a modification to AS/NZS 3500.2 Section 3 Clause 3.2 is required
  • the drain is to be re-laid in an approved material
  • the drain is to be re-laid in a straight line
  • no connections of plumbing fixtures are to be made to the section of combined or shared drain servicing another building under the proposed structure
  • inspection openings to surface or finished level installed at the entry and exit points where the combined or shared drain passes under the proposed structure.

When a section of the below ground sanitary drain cannot be diverted around a new structure you must apply for a VBA plumbing modification.

Email contacts

To enquire about an audit booking, email audits@vba.vic.gov.au 

To enquire about a recycled water inspection, email rcw@vba.vic.gov.au

To enquire or provide information in relation to a rectification notice, email rectification@vba.vic.gov.au

To cancel a drainage inspection, email draincancellation@vba.vic.gov.au

To request a test prior drainage inspection, email testprior@vba.vic.gov.au

Use our online form for all other enquiries.