Menindee Lakes Project
Lake Menindee inlet regulator
Source: Department of the Environment
The Menindee Lakes are located on the lower section of the Darling River in far western New South Wales (NSW). The Lakes are the main water supply storage in the lower Murray-Darling river system, and are an important source of water for NSW, Victoria and South Australia. They are also the principal water supply storage for the City of Broken Hill.
In the 1950s and in the 1960s, weirs, regulators, levees and channels were built to enhance the ability of the Lakes to store and release water. However, the Menindee Lakes are shallow and are located in a hot, windy, semi-arid environment, and experience average annual evaporation losses of over 400 gigalitres of water per year.
The Australian and NSW Governments are developing a project to improve the efficiency of the operation of the Lakes as a water storage. The objective of the project, involving changes to infrastructure and operational arrangements, is to reduce the volume of water that evaporates from the Lakes each year while securing Broken Hill's water supply and protecting the local environment and heritage.
A copy of the Project Agreement between the Australian and NSW governments can be viewed here: Project Agreement for Menindee Lakes Project Management.
Release of Geoscience Australia Reports: Broken Hill Managed Aquifer Recharge (BHMAR) Project
On 12 December 2013, the Parliamentary Secretary to the Minister for the Environment announced the release of Geoscience Australia's (GA) reports on ground water resources beneath the Darling River floodplain at Menindee Lakes.
- New groundwater resources identified near Menindee Lakes - 12 December 2013
Since 2008, Geoscience Australia has undertaken extensive hydrogeological investigations of groundwater resources in the Menindee Lakes region (the Broken Hill Managed Aquifer Recharge (BHMAR) project).
These investigations have revealed 14 discrete areas beneath the Darling River floodplain which contain fresh to acceptable quality groundwater, as well as significant quantities of brackish groundwater. This groundwater is at depths of between 25 and 100 metres in sand and gravel aquifers beneath the Darling River Floodplain study area. The project covered a very wide study area of 7,500 square kilometres but focused investigations on priority sites close to Menindee township. These priority sites were also assessed, using national guidelines, on the capacity of these aquifers to store additional treated surface water.
At the Jimargil site, which is 10-15 kilometres south west of the Menindee township, the groundwater options identified have the potential to provide water supply security for Broken Hill during a drought.
Using technologies more commonly used in oil or mineral exploration, the investigations have provided significant insights into the regional groundwater resources of the Darling River floodplain. This includes a better understanding of where and how these resources are being replenished by river leakage.
For the BHMAR reports, please visit:
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.
Prior to this study, the Darling River Water Savings Project - Part A study undertook preliminary investigations on potential water saving schemes including possible changes to the operation of the Menindee Lakes, securing water supply for Broken Hill and high security users, increasing water use efficiency and providing water for the environment.
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 Darling Water Savings: Options for Environmental Filling No Impacts, Version 2 report identifies 174 gigalitres per year (Long Term Cap Equivalent) of water savings from operational and infrastructure changes at the Lakes.
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 Geoscience Australia to undertake the BHMAR project to identify groundwater resources and aquifer storage options to secure Broken Hill's water supply in dry periods.
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
A video showing aerial surveys done as part of the BHMAR project is also available: