3.2 Wastewater system

Supporting information

The volume reported (96 ML) represents the volume of water held in the wastewater pipes system owned by SA Water at 30 June 2013. It does not include wastewater treatment lagoons. The volumes of water held in the wastewater system, itemised by gravity-fed and pumping pipes, are presented in the following table.

Wastewater system storage volume in the Adelaide region at the end of the 2012–13 and 2011–12 year

Wastewater system

Storage volume at 30 June 2013 (ML)

Storage volume at 30 June 2012 (ML)

wastewater pipes—gravity



wastewater pipes—pumping






Quantification approach

Data source

Geographic Information System (GIS) database, Maximo system.

Provided by

SA Water.


GIS analysis was used to identify wastewater pipes within the Adelaide region. The volume of water held in these pipes was estimated from their total capacity. 

The volumes of water held in pipes were estimated from pipe lengths and nominal diameters (stored in the Maximo system) using the following formula:

π x (D/2) x (D/2) x PL

D = Nominal diameter of the pipe

PL = Pipe length.

Assumptions, limitations, caveats and approximations

  • Given the small variation between reporting years, it was assumed that pipe length remained unchanged in the 2012–13 year, compared to the 2011–12 year.
  • The volume in gravity and pumping wastewater pipes is assumed to be 20% and 100% of capacity, respectively.
  • Pipes without recorded construction dates are assumed to have been constructed before the 2012–13 year.
  • Nominal diameters of pipes were used for the calculation of volumes.
  • The volume reported does not include volumes of water held within wastewater lagoons.

Uncertainty information

The uncertainty estimate was not quantified.