Design standards

The information in this section will help designers and architects understand and implement our protection of services requirements when working near our water, sewer and drainage services.

You will need to follow our Protection of Services guidelines when designing and planning your construction project. Following these guidelines will help you to ensure your works do not impact our water, sewer and drainage services.

These guidelines below identify our minimum requirements for the support of structures built near or over our services. They will help you to develop an appropriate design that protects against:

  • unnecessary restriction of access to our water, sewer and drainage services
  • physical damage to our water, sewer and drainage services
  • physical damage to structures on the property
  • structural load on water, sewer and drainage services
  • costs for future maintenance or emergency repair to those services.

What you need to consider

Please follow this checklist when starting the design process to help you determine if protection of services action will be required.

  • Is protection against structural loads required?
  • What is the settlement and shearing effect of structures built near or over our services?
  • Cantilevered footings should be designed to allow removal of soil within the zone of influence. Soil anchors should not be placed within the zone of influence.
  • Soil and ground characteristics.
  • Potential for natural or accidental flooding of the structure and any need for:
    • drainage of service access tunnels or enclosures provided to protect our services
    • anchoring of the service to prevent flotation as a result of flooding.
  • Permanency of the affected components of the building or structure and whether it is intended for habitable or continuous use.
  • The possibility of impacting our services as work progresses.
  • Impact (dynamic) loads as work progresses, such as vehicle loads, pile driving and site compaction.
  • Method of carrying-out work, such as excavated access ramps, soil stockpiles restricting access.
  • Will sufficient headroom be maintained at all times over any of our services?
  • Access to access chambers, inspection shafts and inspection openings, including:
    • we need to be able to access our services at all times via the property where any of our access chambers, inspection shafts or inspection openings are located
    • an access way of at least 900mm width is required.
  • No part of any structure or installed equipment can be within a zone extending 1.5 m horizontally from the:
    • centre-line of our sewer inspection shaft, rising shaft or inspection opening
    • centre-line at any access chamber.
  • A minimum 2.4m clearance must be maintained where a sewer passes between structures on a single lot.
  • Will you need to amend access chamber or inspection shaft levels, or maintain required soil cover over pipes, where earthworks are required? Access chambers and inspection shafts need to be brought to finished ground level with appropriate protective covers if in a vehicle traffic area.

Consequences of not following our guidelines

Where a structure has been built and it encroaches on an area that cannot be built on, by law the builder is required to underpin the structure. In some circumstances, we may order for the structure to be removed.

Other buried services

Our POS guidelines relate only to work near our buried pipelines. Owners of other buried assets have their own requirements. You can obtain plans of all essential community services, including water electricity, gas and communications infrastructure by contacting Dial Before You Dig.

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