Portfolio Management Statement for the Gwydir catchment 2012-13

Commonwealth Environmental Water Office
September 2012

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The following portfolio management statement is intended to provide guidance on the Commonwealth Environmental Water Office's potential approach to portfolio management in the Gwydir catchment for 2012-13. This statement will be updated during the year as the approach to portfolio management is adjusted in response to actual seasonal conditions. The next routine update is anticipated in November 2012, however, further updates may be released in response to a significant change in circumstances.

Photo of Gwydir River catchment

Gwydir River catchment.

Photo by Simon Banks © CEWO

Date issued: 07 September 2012

Recent Water Availability

In 2011-12 the Gwydir catchment experienced very wet conditions and correspondingly very high levels of water availability. Copeton Dam is currently at around 99 per cent of capacity and most general security accounts (managed under a continuous accounting system) remain at their maximum of 150 per cent (1.5 ML/share). per cent (1.5 ML/share).

Commonwealth holdings (as at 1 August 2012)
Entitlement typeEntitlement Held (GL) Entitlement Held – Long-term Average Annual Yield (GL) Carryover from 2011-12 (GL) Water Available (GL) Forecast Maximum Water Available in 2012-13(GL)
High Security 0.4 0.4 0 0.4 0.4
General Security 89.5 32.2 134.3 134.3 134.3
Supplementary# 19.1 3.6 0 - -
Total 109.0 36.2 134.3 134.7 134.7

Note: In accordance with the NSW Water Sharing Plan for the Gwydir Regulated River Water Source (2004):

# Availability of supplementary water is subject to announcement.

Commonwealth environmental water available in 2012-13

The opening account balance of Commonwealth Environmental Water's regulated entitlements for 2012-13 was 134 GL. High security entitlements have received an opening allocation for 2012-13 of 100 per cent. Total allocations of 56 per cent have been made to general security entitlements, however additional water did not accrue to the Commonwealth account as it was already at the maximum balance. These allocations are significantly higher than the long-term average, which means that the Commonwealth Environmental Water Office has, like all other entitlement holders, substantial volumes of water available.

Allocation water can be used, traded or carried over to subsequent years depending on the nature of the source entitlement and the legal framework which applies to the management of Commonwealth environmental water. Near-full public storage limits the degree to which inflows can be captured and allocated, and new allocation announcements will be heavily influenced by the account balances of water users in the Gwydir. As the Commonwealth account is currently full, use or sale would need to occur before any additional volume from allocation announcements could be received.

The use limit that applies to allocations to general security entitlement limits the total volume of regulated allocation available to a maximum of 112 GL. Supplementary access during the year is possible, though less likely in lower inflow conditions.

Water use options in 2012-13

The Commonwealth Environmental Water Office has developed water use options for up to 40 GL of regulated allocations, which may vary depending on seasonal and operational considerations.

Commonwealth supplementary water may be utilised if access is triggered during peak environmental watering demand periods (Dec-Feb).

Further information on environmental water use options is available on Annual Water Use Options 2012-13: Gwydir River Catchment

Trade in 2012-13

The Water Act 2007 provides for the trade of Commonwealth environmental water (allocations and entitlements) and specifies the conditions under which sales may occur. In the Gwydir there is potential to trade allocations in the current situation of high water availability, if there were to be a demand for purchase of that water in this catchment. However, given high water availability and all entitlement owners having high allocation it is not envisaged that this demand would materialise in the short term. Accordingly it is not envisaged that the Commonwealth Environmental Water Office will trade allocation in the short term. The Commonwealth Environmental Water Office will provide further information to the water market prior to undertaking any trading action.

Carryover into 2013-14

Assuming no sale of regulated allocations and excluding substitution of supplementary allocation, Commonwealth Environmental Water Office's opening balance of regulated allocations for 2013- 14 is forecast to be in the range of 94-134 GL. The range reflects uncertainty as to the volume and timing of environmental water use (which will create space within the Commonwealth accounts) and the timing of any additional allocation announcements.

Multi-year planning of environmental water use is particularly important in the Gwydir system given the long-term low reliability of general security entitlements. An account balance in the above range will provide for multiple years of environmental watering under a range of climate scenarios.

Bar charts shows as at 1 August 2012, the Commonwealth held 15% of the Gwydir catchment irrigation entitlements, measured in terms of long-term average annual yield. The remaining 85% were held by other entities.

Proportion of Gwydir irrigation entitlements held by Commonwealth (by total long-term average annual yield)

Bar charts shows that as at 1 July 2012, Commonwealth water accounts in the Gwydir catchment contained 134 GL of allocation. This was approximately 10% of the 1361 GL capacity of the Gwydir's major storages.

Carryover of Commonwealth environmental water as a proportion of Gwydir's major storage capacity

Cover of Portfolio Management Statement for the Gwydir catchment 2012-13

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