Adelaide

The volume reported in the water accounting statement (14,742 ML) represents background leakage from the pipes in the water, recycled water and irrigation water supply system, as shown in the table below.

Data source

SA Water: Geographic Information System (GIS) database.

2009–10 National Performance Report (NWC 2011)

Barossa Infrastructure Limited (BIL): map of pipe network and estimates of unaccounted-for irrigation water.

Data provider

SA Water.

South Australian Department for Water.

Method

This term has two components: leakage from urban systems and leakage from irrigation systems.

Leakage from urban systems

GIS analysis was used to calculate the length of SA Water pipes within the Adelaide region. The leakage volume was calculated by multiplying this length and the 2009–10 mains loss rate for Adelaide of 3.6 kL/km/day (NWC 2011).

Leakage from irrigation systems

The length of the BIL pipe network was multiplied by a leakage rate of 2.66 kL/km/day (BIL manager, pers. comm., 2010) to estimate the total leakage for 2009–10.

Uncertainty

Ungraded.

Assumptions, approximations and caveats/limitations

Leakage from urban systems

• The Adelaide loss rate was assumed to be representative of conditions within the Adelaide region.
• All pipes identified in the map were assumed to have been constructed before the reporting period.
• Leakage from the water distribution systems occurred due to background leakage from the potable and recycled water systems.
• Leakage from bulk transport pipelines (Mannum–Adelaide, Murray Bridge – Onkaparinga and Swan Reach – Stockwell) and wastewater pipelines was assumed to be negligible.

Leakage from irrigation systems

• The area serviced by BIL extends beyond the boundary of the Adelaide region. It was assumed that the length of BIL infrastructure outside the Adelaide region is insignificant.
• Estimates of unaccounted for irrigation water were provided for the 2009–10 water year. It was assumed that these estimates apply to the reporting year.
• It was assumed that leakage from infrastructure is the only source of unaccounted water.