South East Queensland
11.5 Delivery of water from outside region to urban water system

The volume for the line item during the 2012–13 year was 24,514 ML

This line item consists of water transferred into the urban water supply system (including potable and non-potable water), wastewater system and recycled water system from outside the South East Queensland (SEQ) region.  

There were no wastewater, recycled water or non-potable water transfers into the SEQ region.

The following table shows the potable water imports to the SEQ region during the 2012-13 year.

 

Potable water imports into the South East Queensland region

Import	2013 Volume
Water authority: Seqwater	(ML)
Northern Pipeline Interconnector and local reticulation system (mostly surface water with a small component of groundwater)	14,772
Eastern Pipe Interconnector (groundwater intake for treatment and supply at North Stradbroke Island water treatment plant)	9,738
Water supply from Toowoomba Regional Council across the SEQ region boundary to the Queensland Urban Utilities (QUU) area (Preston community) within the region	4
Total SEQ region	24,514

 

South East Queensland's urban water system comprises three sub-components: 

• urban water supply system
• wastewater system
• recycled water system.

There are four main sources of water for SEQ's urban water supply system:

• surface water (11.2 and 11.12 )
• groundwater (11.3)
• desalinated water (11.6)
• imported water (11.5). 

The water intake to the urban water supply system (251,894 ML) is from four sources: surface water (224,420 ML), groundwater (158 ML), desalinated water (2,805 ML), and imported water (24,514 ML).

During the 2012–13 year, the volume of water delivered to urban users (potable and non-potable water supplied amounting to 219,392 ML) was the major outflow from the urban water supply system. This supply for urban consumption represented about 87% of the total outflow. Approximately 11% of the outflow was leakage (19.3 Urban water system leakage to groundwater) and 2% was remaining losses.

Schematic diagram of water inflows and outflows during the 2012–13 year for South East Queensland's urban water supply system; line item numbers are provided in brackets

Seqwater: WaterHub database; Unitywater: Bureau of Meteorology code data

Seqwater; Unitywater.

Seqwater has provided the volume of water supplied to South East Queensland (SEQ) water grid from its water treatment plants (WTPs) during the 2012­-13 year. Among them, three water treatment plants namely Landers Shute WTP, Noosa WTP and Ewan Maddock WTP are located in Unitywater area and (northerly) outside the National Water Account SEQ region. It can be considered that a portion of water supplied to the water grid from these WTPs are used in the Unitywater area and the balance has delivered to SEQ region as water import to the region  via Northern Pipeline Interconnector and local reticulation system supply (i.e. supply from the Landers Shute WTP to the local area within the SEQ region) .

The volume of water used in the Unitywater area outside the SEQ region can be estimated subtracting the volume of water used in SEQ region by Unitywater from the total volume of potable water supplied to Unitywater by Seqwater during the reporting year.

 

The derivation of the imported volume via the Northern Pipe Interconnector and local reticulation system is shown in the following Table.

 

Water import via Northern Pipeline Interconnector and local reticulation system

Component	Volume ML
(a) Supply to the water grid in the Unitywater area outside the NWA SEQ region Total of:  Landers Shute WTP (31,836 ML) + Noosa WTP (3,370 ML) + Image Flat WTP (4,225 ML):	39,431
(b) Water intake for off-grid water supply to Unitywater area outside the NWA SEQ region (Total of: Kenilworth WTP (64 ML) + Ewen Maddock WTP (2,159 ML)	2,223
(c) Groundwater intake and supply to Unitywater area outside the NWA SEQ  region (Bribie Island Bore fields: Banksia Beach WTP)	1,143
(d) =(a) + (b) + (c); Total intake by Seqwater in the Unitywater area outside the NWA SEQ region	42,797
(e) Volume of water received by Unitywater from Seqwater outside the NWA SEQ region Taken as the difference of between the total volume supplied by Seqwater to Unitywater (reported by Seqwater): 59,009 ML, and the volume received by Unitywater within the SEQ region: 30,984 ML (reported by Unitywater).	28,025
Import via Northern Pipe Interconnector and local reticulation system: Difference (d) - (e): Taken as the difference between the intake by Seqwater in the Unitywater area outside the NWA SEQ region and the volume of water received by Unitywater from Seqwater outside the NWA SEQ region.	14,772

The method adopted to calcualte the water imports via Northern Pipe Interconnector and local reticulation system includes the supply to the local area within the National Water Account SEQ region supplied by Landers Shute WTP.

The uncertainty was not quantified.

Seqwater: WaterHub database.

Seqwater.

The volume of potable water import via Eastern Pipe interconnector was considered to be equal to the  volume of groundwater intake for treatment and supply at  North Stradbroke Island WTP.

North Stradbroke Island WTP was based on one meter, this cannot be broken down into the volume transferred to the SEQ region and the volume used locally to service communities on North Stradbroke Island. A slight overestimate of the volume transferred into the SEQ region can occurr, although this volume is expected to be minor.

Derived from metered data. Ungraded.

Meter readings and charge details as reported by Toowoomba Regional Council and Queensland Urban Utilities (QUU).

Toowoomba Regional Council; Queensland Urban Utilities.

Water bill charged by the Toowoomba Regional Council to QUU.

None.

Not quantified.