Paul Simpson Consulting Pty Ltd
Advice to the Commonwealth Environmental Water Office
About the document
The Commonwealth Environmental Water Office engaged Mr Paul Simpson to investigate the impact that current water management arrangements have on achieving environmental outcomes under low flow conditions and potential options to address those impacts.
Mr Simpson’s report identifies key impediments to achieving event-based environmental flow outcomes, including:
- without additional protections the nature of unregulated licences makes water recovery less useful than regulated systems;
- upstream flow constraints in regulated tributaries; and
- the degree of take permitted during low flow periods under the 2012 WSP, particularly by A Class licences.
The report also outlines options for statutory changes to improve low flow outcomes, including:
- protection within the Barwon-Darling Water Sharing Plan for flow events that have arisen as a result of the release of environmental water in the northern regulated tributary systems;
- formal recognition that supplementary access should be withheld whenever the flows have arisen as a result of the release environmental water in the regulated tributary systems; and
- implementation of individual daily extraction limits and total daily extraction limits at rates more closely matched with the installed pump capacity for that class at the time the Water Sharing Plan was originally made (2012).
This report has provided important information that has informed the Commonwealth Environmental Water Office’s contribution to policy initiatives to protect water for the environment, including the New South Wales Water Reform Action Plan.
The Commonwealth Environmental Water Office has supported several projects to improve our understanding of the ecological importance of low flows in the Barwon-Darling River and the influence of water resource development and river regulation on the river’s hydrology, including:
- Characterising the ecological effects of changes in the ‘low-flow hydrology’ of the Barwon-Darling River
Other information describing the low flow hydrology of the Barwon-Darling and the influence of current water management arrangements can be found on the MDBA website: Barwon–Darling ecological needs and hydrology.
Darling River at Bourke. Photo: Nerida Sloane