Sustainable Groundwater Management
Under the National Water Initiative , the Australian, State and Territory Governments have acknowledged the importance of groundwater and are committed to a "whole of water cycle" approach. Important components of this strategy are to:
- improve our knowledge of groundwater surface water connectivity, with significantly connected systems to be managed as one integrated resource
- complete the return of currently over-allocated or overused systems to environmentally sustainable levels of extraction
- improve understanding of sustainable extraction rates and regimes, and develop common approaches to achieving sustainability
- develop better understanding of the relationship between groundwater resources and groundwater dependent ecosystems.
In response to a deepening water availability crisis and the threat of climate change, particularly in the Murray Darling Basin, the Australian Government, through the Council of Australian Governments (COAG), has established the National Water Initiative and the National Water Commission to champion reforms in water management, including the recently adopted National Groundwater Action Plan. An example of ongoing water management reform is the establishment of the Murray-Darling Basin Authority , an independent authority which will develop and implement sustainable surface and groundwater management plans of the Murray Darling Basin by 2011.
Currently, groundwater is managed at state or local scales. Groundwater management plans vary across jurisdictions and may cover all aquifers or only a portion of aquifers in respective regions. Development of area-specific groundwater management plans requires an understanding of geology, hydrogeological settings, hydrodynamics, environmental water requirements, historical water use practices and local water use, present and future. Water sharing arrangements are typically governed by state legislation, in areas of highly developed groundwater resources, via specific groundwater management plans. The Australian Government can support state and territory water management through agreements tied to funding programs.
The Australian Government is directly involved in water management where resources cross state boundaries. Cross border agreements exist for the Murray Darling Basin, the Lake Eyre Basin, the Great Artesian Basin, the Queensland/New South Wales Border Rivers, the Snowy River, and the Victoria/South Australia Border Groundwater Area.
Both surface water and groundwater resources have suffered from unsustainable consumption or extraction and over allocation of resources with ongoing and worsening environmental consequences including land degradation, decreased water quality and declining biodiversity.
Sustainable management of groundwater resources is imperative to the agricultural, industrial, urban, rural and environmental viability of Australia.
Such management requires not only a robust scientific basis but also ongoing monitoring of groundwater allocations/licensing, use, water levels, and groundwater quality.
Understanding of the variability and range of hydrogeological settings and Australia's demands on aquifer systems is crucial to effective management practices.
Sustainable allocation of groundwater resources will require catchment and aquifer management plans that clearly integrate groundwater and surface water systems. This will require an accurate catchment and aquifer water balance to develop management plans which recognise the long timeframes of aquifer and catchment interaction. Integrated management plans must allow for sufficient environmental flow in groundwater systems to maintain groundwater dependent ecosystems. For groundwater to provide a buffer against drought, storages cannot be depleted; allocation must be considerably less than the average annual sustainable yield.
The Water Act 2007 requires the new Murray-Darling Basin Authority to prepare a Basin Plan. The central element of the Basin Plan will be the introduction of sustainable and integrated diversion limits on groundwater and surface water extraction.