Menindee Lakes Project
In 2010 the NSW and Australian Governments signed a Memorandum of Understanding (MOU) to guide the implementation of the Australian Government's 2007 commitment to a Menindee Lakes project. The project is aimed at reducing evaporation and improving water efficiency at Menindee Lakes; securing Broken Hill's water supply; protecting the local environment and heritage; and returning up to 200 gigalitres (GL) per year to the environment.
In June 2011 NSW advised that it considered the MOU had ceased to have effect.
Darling River water savings project — Part B study
In March 2010, the Australian and NSW Governments completed the Darling River Water Savings Project (DRWSP) Part B study. This jointly funded study investigated options to reduce evaporation at Menindee Lakes, improve the water supply and management of the Darling River system, and secure Broken Hill's water supply.
The most recent studies to support the implementation of a Menindee Lakes project:
Darling Water Savings: Options for Environmental Filling No Impacts, Version 2
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) has undertaken a number of hydrological modelling studies to identify management options for Menindee Lakes that would result in no impact on downstream users but maximise water for the environment and significantly reduce evaporation losses. The key findings from the Darling Water Savings: Options for Environmental Filling No Impacts, Version 2 report are:
- the water saving option that best meets the criteria specified by the Hydrological Modelling Working Group under the MOU, would comprise
- the revised proposed Basin Plan environmental filling rules, with a 185/185 NSW/MDBA operating rule
- the Lake Menindee outlet increased to 14,400 ML/day
- Broken Hill's water supply secured and 28 GL of NSW General Security Murray Licence purchased but not used.
- Under this option the proposed environmental filling requirements in Lakes Menindee and Cawndilla could be met, Broken Hill's water supply would be secured, and there are 174.0 GL/y (LTCE) of savings.
- There were a number of positive impacts associated with the proposed option, including increased flows to the lower reaches of the Darling and Murray (including the lower lakes and Coorong), improved allocations in dry years, reduced average restrictions in South Australia, and improved allocations in the Lower Darling and Victoria. There are improved diversions as a consequence of the improved allocations.
- The report also concludes that under the option discussed there would be some minor downstream salinity impacts, which could be offset by using salinity credits owned by the Commonwealth.
Broken Hill managed aquifer recharge (BHMAR) project
To identify options for securing Broken Hill's water supply, the Department commissioned Geoscience Australia to undertake a study of known groundwater resources and aquifer storage options within 150km of Broken Hill (the 'Broken Hill Groundwater Resource Assessment').
Based on positive findings from this study, the Department commissioned further work by Geoscience Australia to help identify realistic groundwater options to secure Broken Hill's water supply in dry periods. The BHMAR project surveyed groundwater resources and aquifer storage options in the region.
The first two phases of the project identified that the use of sustainable groundwater resources and an aquifer storage system would be feasible. More detailed on-ground geological and engineering assessments are being finalised. Reports include:
A video showing aerial surveys being done as part of the BHMAR project:
For further information on the BHMAR Project, please visit Geoscience Australia - Broken Hill Managed Aquifer Recharge web page.
Professional Opinion, Securing Broken Hill's Water Supply: Assessment of Groundwater Extraction and Conjunctive Water Supply Options at Menindee Lakes
In April 2011, as part of the BHMAR project, Geoscience Australia provided a professional opinion, Securing Broken Hill's Water Supply: Assessment of Groundwater Extraction and Conjunctive Water Supply Options at Menindee Lakes, indicating with a high level of confidence that groundwater resources, used in conjunction with the existing surface water supply from the Darling River and Menindee Lakes, would have the capacity to secure the water supply for Broken Hill.
- Professional Opinion, Securing Broken Hill's Water Supply: Assessment of Groundwater Extraction and Conjunctive Water Supply Options at Menindee Lakes