Commonwealth Environmental Water Office
Update prepared: 14 March 2013
Photo by Arthur Mostead © MDBA
This portfolio management statement outlines the Commonwealth Environmental Water Office's (CEWO) current potential approach to the use, carryover and trade of Commonwealth environmental water in the Namoi catchment (Upper and Lower) for the remainder of the 2012-13 water year.
This statement will continue to be updated as the approach to portfolio management is adjusted in response to actual seasonal conditions. The next routine update is anticipated around June/July 2013, however, further updates may be released in response to a significant change in circumstances.
Recent Water Availability: The Namoi catchment commenced 2012-13 with very high levels of water availability, however hot and dry conditions have recently prevailed. While Split Rock Dam has remained at approximately 90% of capacity, Keepit Dam has been drawn down rapidly through spring and particularly summer and is now at approximately 45% of capacity. Allocation announcements to general security entitlements have been low, totalling 32.6% of entitlement at the last announcement in early October 2012.
|Entitlement type||Entitlement Held (GL)||Carryover from 2011-12 (GL)||New allocations in 2012-13 (GL)||Estimated water that has been delivered in 2012-13 (GL)||Current Commonwealth allocations (GL)|
|Upper Namoi (General Security)||0.1||0.1||0.1||0.1||0.0|
|Lower Namoi (General Security)||6.1||12.2||0.0||7.6||4.6|
- Slight discrepancies may exist due to rounding.
In accordance with the Water Sharing Plan for the Upper Namoi and Lower Namoi Regulated River Water Sources 2004:
- Upper Namoi (General Security), carryover plus annual allocation cannot exceed 100%, maximum carryover of 50%.
- Lower Namoi (General Security), maximum allocation account balance at any time of 200%, maximum carryover of 200%, maximum annual use of 125%, maximum three yearly use of 300%.
- Use, account and carryover limits are expressed as percentage of entitlement held.
Commonwealth environmental water availablity and use in 2012-13 (up to 28 February 2013)
Including the 100% opening allocation to Upper Namoi general security entitlements, CEWO commenced the year with 12.3 GL of allocation. Allocations to Lower Namoi general security entitlements have not resulted in additional water being received as the allocation account was already at the maximum balance.
In February 2013, 7.7 GL of Commonwealth environmental water extended the duration of natural flows associated with Cyclone Oswald at approximately 2,000 ML/d to provide additional access to in-channel habitat and provide a more naturally gradual flow recession. A gradual recession provides native fish, and other in-stream species, opportunity to retreat to suitable habitat to shelter. This constituted the first delivery of environmental water in the Namoi catchment.
Anticipated water availability and use in remainder of 2012-13 (post 28 February 2013)
The announcement of any additional allocations is subject to the NSW Office of Water's considerations regarding dam inflows and other factors. While environmental water use has made some space within CEWO accounts to receive new allocations, CEWO is not anticipating receiving any significant allocations for the remainder of 2012-13.
No further environmental watering will be conducted in 2012-13 as the February 2013 environmental water delivery fully utilised the water sharing plan's limit on CEWO's annual water use.
Further information on environmental water use in the Namoi is available at Namoi catchment.
Trade in 2012-13
The Commonwealth Water Act 2007 provides for the trade of Commonwealth environmental water (allocations and entitlements) and specifies the conditions under which sales may occur. No Commonwealth environmental water has been traded this year within the Namoi. Minimal trade of regulated allocation by other water market participants was observed until summer, when the value of water traded leapt to historically high levels. Recent rain events have significantly diminished activity.
CEWO is not intending to trade allocations or permanent entitlement in the Namoi over the remainder of 2012-13. Further, CEWO does not intend to trade anywhere until it has addressed matters arising from the making of the Basin Plan and issues that were raised in recent consultation with industry groups. These include implementing protocols to address concerns about the potential for insider trading.
All intentions are largely unchanged from those expressed in the Statement released in December 2012 and further information would be made widely available should they change
Carryover of Commonwealth environmental water into 2013-14
It is estimated that 4.5 GL of Commonwealth environmental water will be carried over into 2013-14. Additional entitlements entering the Commonwealth's holdings may alter this estimate. Allocation carried over will be available for environmental watering in the Namoi catchment in 2013-14, for which options and plans are currently being developed.
Carryover can be used to implement environmental water options from early 2013-14. Further information about carryover of Commonwealth environmental water can be found here: Information on carryover.
Proportion of Namoi irrigation entitlements held by Commonwealth (by total long-term average annual yield)
Regulated Commonwealth environmental water allocations as a proportion of Namoi major storage capacity