Sydney
17.16 Other delivery of allocated surface water

Supporting Information

The volume for this line item is 7,532 ML.

The Sydney Catchment Authority (SCA) manages banked environmental flow in the Sydney region.

SCA released a volume of 28 ML/day of the banked environmental flow from Warragamba Dam from 5 October 2010 to 30 June 2011. This event used 7,532 ML.

Reconciliation of this line item is shown in the following table.


Calculation of other surface water liability for 2010-11 year
Calculation
 Line item
 Volume (ML)

 

5.6 Other surface water liability – opening balance

9,795

add

21.6 Other surface water liability increases

3,100

less

17.16 Other delivery of allocated surface water

7,532

less

13.6 Other surface water liability decreases

0

equals

Closing balance (as at 30 June 2011)

5,363

Quantification Approach

Data Source

SCA and NSW Office of Water agreement; Daily Return System (DRS) database; SCA compliance reporting to the NSW Office of Water.

Provided by

SCA.

Method

For 2010–11, the released banked environmental flow volume was derived from orifice-rating tables and stream gauging downstream of environmental flow release from Warragamba Dam. The banked environmental flow was reduced by the released volume.

Assumptions, Limitations, Caveats and Approximations

Nil.

Uncertainty Information

The volume is based on measured data. Estimated uncertainty based on accuracy of stream gauging is +/– 10%.

Comparative year

The following table compares the value at 30 June 2010 reported in this account with the corresponding value reported in the 2010 Account.

 

Comparative information from the 2010 Account for line item 17.11

2011 Account line item

2010 Account line item

Value reported in the 2010 Account (ML)

Value reported in the 2011 Account (ML)

Additional information

17.16 Other delivery of allocated surface water

14.7.9.7 Allocation diversion of regulated flows – other lumped holders

2,450

2,450

Change in line item name and number