The Vision of the South East Catchment Water Management Board
for the SE Catchment
Hugo Hopton
Abstract The SECWMB wishes to set a new direction for the sustainable management of the waters of the South East of South Australia, second only to the River Murray in importance to the state. Over the last 100 years the region’s flat landscape has been cleared of native vegetation for extensive rain-fed grazing enterprises. Exploitation of the waters has been incremental to crisis point. Water management has been sound but reactive, water-focussed but narrow. In its long-term catchment plan, the Board, aspires to achieve balance between current and future economic, social and environmental demands, as the natural resources move to a new equilibrium and for the well-being of the water resource itself.. The Board will need to determine how to value of the natural environment, including the intrinsic value of sub-surface cavities, and the waters associated with them. Introduction
The Board is required to consider all waters in its area, including surface waters, waste waters, reclaimed waters and the waters below, the groundwaters. Background
Discussion
An early stage in the process for the Board is to determine the definition of sustainability in the context of the Board region. Peter Ellyard in his book “Ideas for the new millennium” discusses sustainability, and suggests that ‘sustainable development ‘ may be a more inclusive concept to ‘ecologically sustainable development’. He argues that including the word ecologically has satisfied the environment movement and natural resource agencies of government, but made ESD a concept of marginal importance to the community and to business. To lift above this, he suggests that: “A sustainable society is one which can exist more or less indefinitely because it is both respectful of and able to change and adapt to its natural limits”. He goes on to question, if, with current knowledge, the elements of sustainability:
The Board, in considering its vision for the catchment, will need to determine if it, in association with the community, will be focussing on sustainability in its broadest sense. Alternatively, it could as Ellyard suggests, singly consider the elements of economic, ecological, social and cultural sustainability for the waters of the catchment of the South East. Added to this, the Board will also have to decide whether or not to develop a hierarchy of sustainability at strategic level, or whether to examine each issue on its merits. Should ecological sustainability dominate over economic sustainability. For example, the comprehensive catchment water management plan will certainly have to discuss the rate at which the fossil waters of the confined aquifer should be used. Should they be eked out over 1,000 years, or used for economic benefit in a much shorter period of time. Before the debate on sustainability can be openly initiated, the Board faces a significant challenge. Currently water allocation is high in the mind of many sections of the community, and has become quite political. While some of the issues are similar, such as declining water qualities in some areas, the heat in this debate reflects the effects of current and future water allocations on individuals or enterprises, rather than the community as a whole. To avoid this distracting the emphasis on developing a vision of a sustainable catchment, the Board must design and run a process to allow the water allocation plans to be developed in a fair and consultative way. This process, because of the timelines confronting the Board will be concurrent with the comprehensive catchment water management planning process. The Board will seek to keep the two planning processes separate in the community’s minds, while ensuring the two processes connect at relevant times on issues of common interest. The examination of economic, social, ecological and cultural issues will differ in scale and scope between the two processes. The comprehensive catchment water management plan will set direction for the very long term, while water allocation plans will focus on the immediate. In working with the community to set a vision for the catchment, the Board must also contemplate, and assist the community to contemplate the external influences currently at play. Some of these are described below: 1. Water is an increasingly politicised issue, locally through to internationally;
This means that the development of a vision for the catchment cannot and should not rest in the artefacts of past management, or even resource sharing. The wider community and even the global community have an interest and a stakeholding in the well-being of the South East’s water resources. The catchment is, therefore, very much part of the global community as a result of the globalisation of environmental issues. The sound management policies currently in place in the Board’s region indicate the prudence and strength of character of the former water resources committees active in the region. Existing and modified policies need to remain in place while the future direction arises from the development of the comprehensive catchment water management plan. Below are just some issues which may be explored in the development
of the vision and the consequent direction in catchment management.
Vision for the catchment
Societal Issues
The value of the vision and the comprehensive catchment water management plan is from the energy for change it engenders. Fundamental is measuring the progress and monitoring the effects on the four elements of sustainability describes above. Underpinning the vision for the catchment must be an effective monitoring network, recording a well-considered range of parameters. The South East is certainly fortunate to have a very extensive groundwater monitoring system. The region needs to add to this a monitoring framework which will also yield sound information on some of the less tangible parameters. This may include issues such as the health of below ground cavities, the formations within them, their water features and the life associated with them. Conclusion
The vision for the catchment must not only accommodate the current management needs of the water resources of the catchment, but must excite the community about the ecological, economic, social and cultural opportunities the future can hold. References
Appendix 1 Physical Description of the board area
Investment in irrigation continues to expand as farm businesses and new investors look to an increasingly globalised market, and one in which traditional commodities attract lower real prices. Towns and industries continue to grow, with that growth bringing an increasing reliance on the water resources of the region. Farm gate value of irrigated products exceeds $100 m annually. In addition, industries such as paper pulp and potato processing use groundwater and add substantially to the economy. The South East possesses water resources that are second only to the
River Murray in their potential importance. The region’s groundwater
resources principally lie in two aquifers: an upper unconfined aquifer,
and a deeper confined aquifer, separated from the upper aquifer by a confining
bed of clays.
The unconfined aquifer is recharged annually by rainfall, with recharge ranging from 10 to 15 mm per year in the north to more than 150 mm in the south, depending on rainfall, vegetation cover and soils. It has a hydraulic gradient towards the coast with a watertable elevation of more than 80m AHD east of Naracoorte to less than 5m AHD near the coast. The depth to groundwater ranges from over 20 metres around Mt Gambier to 2 metres over much of the central area. The lateral groundwater flow ranges from 1 to 40 metres per year. The quality of the unconfined aquifer varies across the region, with low salinities in the south (< 500 mg/L) to very high salinities in the north-west of the region (> 7000 mg/L). In a number of areas the quality of the unconfined aquifer has been affected by waste disposal, irrigation and agricultural practices and changing land use. The most important influence in unconfined aquifer water quality is salinisation resulting from locally concentrated use of the groundwater. The confined aquifer contains older water, principally recharged in western Victoria, as well as some locally restricted recharge areas, such as near Nangwarry. Vertical leakage between the two aquifers occurs in some areas. In the west of the region there is sufficient confined aquifer pressure to enable bores to flow freely at the ground surface. The depth to the confined aquifer ranges from less than 30 metres in the Glencoe area to more than 300 metres along the south coast. Salinity ranges from 600 to over 3,000 mg/L. |