3.2 Wastewater system
The volume reported (96 ML) includes water held in the wastewater pipes system owned by SA Water, but does not include wastewater treatment lagoons. There was little new wastewater pipe construction in the 2011–12 year. The volumes of water held in the wastewater collection system, itemised by gravity-fed and pumping pipes, are presented in the following table.
|Wastewater system||Storage volume at 30 June 2012 (ML)
||Storage volume at 30 June 2012 (ML)
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
- 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 2011–12 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.
This line item corresponds to line item 3.2 'Wastewater collection system' reported in the 2011 Account.