Below ground sanitary drainage
Do I have to book a live underground sanitary drainage inspection when I am installing a septic tank and associated drains?
No. You will have to lodge a compliance certificate upon completion of the work.
Do I have to book a live underground drainage inspection for underground stromwater drainage work?
No, but you must lodge a compliance certificate upon completion of the work, if the total cost of the work is equal to or greater than $750.00.
Do I have to book a live underground drainage inspection for underground stromwater drainage work?
No, but you must lodge a compliance certificate upon completion of the work, if the total cost of the work is equal to or greater than $750.00.
Who will be inspecting my live underground sanitary drainage work and what aspects of the job will they be looking at?
The Plumbing Industry Commission has engaged Bilfinger Berger Australia to perform these inspections. The inspections are carried out when the pipe laying is completed but before the drain is backfilled.The inspection parameters normally include an examination of the following features:
- Drain venting - drain connection point
- BT or BT omitted - approved materials
- Bedding and bedding materials - gradient
- Minimum cover requirements - backfill material
- Infiltration protection - integrity of cut and seal
- Surcharge protection (Overflow Relief Gully or Reflux Valve).
What are the minimum requirements if a combined drain is not able to be diverted around a building on the same property?
- The installation of drains under buildings must comply to AS3500, and in particular Part 2, Section 3
- The alignment of the drain must be straight
- No connections are to be made to the drain under the building
- An inspection opening to surface is to be installed at both the entry and exit points of the drain
- Un-plasticised Polyvinyl Chloride (UPVC) and Cast Iron are approved material
- In the case where permission is sought to use an existing cement jointed vitrified clay pipe drain permission will not be granted.
What are the minimum requirements for combined drains external of the building?
In the case where a full site redevelopment has taken place, then any cement jointed vitrified clay pipe drain is to be renewed to the point connection.
If the BT has at some stage been replaced in either cast iron or UPVC and is in good order then the existing BT installation may remain but will be subject to a water test.
BT shafts must be clear of easements and within the property boundary, in the case where the building is constructed to the building line of the property the BT shaft will need to be recessed into the external wall allowing access for maintenance and rodding of the shaft; or alternatively, and with council permission, the shaft may be installed in the easement or right of way, provided a heavy cover is used and a 100mm vent branch is taken off for the vent which is to be recessed into the boundary wall.
