Brief History of Irrigation Development in Australia

In the first decade of the 19th century, Australia's agriculture dealt mainly with sheep, wool, beef and wheat production. The comparatively slow development of the irrigation sector compared with that of dryland reflects the high river flow variability characteristic of Australia, and the associated prerequisite of securing water supply through dam development. Despite the greater water resources in northern Australia, the history of urban and market access have largely dictated the geography of the irrigation industry, which is today dominated by development in the southern half of the Murray-Darling Basin (MDB) (see case study 1).

From 1901 (since the Federation) to the early 1990s, Australian governments were determined to 'drought-proof' the continent through river development (Tisdell et al., 2002). Development of water courses and provision of security of supply were seen as a public good, necessary for the development of the nation. As agents for water resources, the states were the primary developers of surface water infrastructure. This resulted in extensive dam building and associated engineering works, which are represented by the Snowy Mountains hydroelectric scheme, a huge engineering feat that captures and redirects 5044.5 l (1121 gallons) of water from its natural course down the Snowy River into the MDB system. The dam's construction (which spanned 25 years and involved more than 100,000 workers) illustrates the level of cooperation between governments, which was fuelled by the general optimism of the development era.

Irrigation development was associated with concentrated efforts to settle high potential areas following the two World Wars - normally discussed as 'soldier settlement'. Private irrigation trusts were also established in the late 19th century, but were relatively small scale compared to state-sponsored developments. Public investments for dam construction, channel infrastructure and promotion of expansion within the industry made for an industry dominated by the heavily subsidized surface water irrigation industry. In contrast, groundwater development has been sparse, privately financed and localized, with a greater emphasis on non-agricultural use, partly due to the extensive development of surface water resources.

The goodwill generated by shared development ambitions and successful collaborative social and engineering projects have served intergovernment communication through similar jargon and shared responsibilities. This history underpins the relatively cooperative endeavour of water reforms today.

The development agenda of the early and mid 20th century declined since the 1970s, with the realization that the resource base in key areas (notably the MDB) was being jeopardized. It was realized, in the late 1970s, that the licensed volumes within the MDB exceeded the available supply on which interstate water-sharing arrangements were based (Turral, 1998). It was clear that the value of building additional dams would therefore come at a cost of filling existing storages. Quite clearly, in the developed irrigation sites, there was no surface water to harvest and any further development would reduce the security of supply to existing users.

Furthermore, the irrigation industry was increasingly aware of the environmental overheads of their own practices. The expense and political sensitivities relating to the riverine impact of salinity were expanding, and there was growing pressure for irrigators to internalize these costs by improving farm management. Rivers and inland wetlands were impaired by reductions in in-stream flows and, in some cases, through inversion of flow patterns, as irrigation water is released from dams in summer, whereas natural flows are mostly concentrated in winter in south and east Australia.

In the early 1980s, issues surrounding the proposal to dam the Franklin River resulted in an explosion of public debate and environmental awareness relating to river development. The Franklin Dam was a Tasmanian proposal, which was successfully halted by the Commonwealth Government on the basis of the World Heritage listing.

In terms of water development, the significance of the Franklin Dam was twofold:

1. It confirmed (by precedent) a Commonwealth power to intervene in activities previously held to be state responsibilities.

2. It clearly demonstrated, through polls, the public priority of environmental sustainability.

Coincidentally, the state governments were also reluctant to continue to subsidize the operation, maintenance and replacement of irrigation systems. As a result they were corporatized (Victoria) or fully privatized (New South Wales, NSW) in the 1990s, and are now run by professional managers responsible for farmer-dominated management boards. The governments also recognized the full environmental and financial costs of water diversion and transmission, and maintenance overheads of the existing infrastructure. Tisdell et al. (2002) clearly summarize:

[A] singular construct of water capture and reticulation, which traditionally reflected the primacy of national development, was increasingly seen as failing to capture the multiplicity of water outputs, ecosystem functions and the changing societal objectives of maintaining in-stream values and water quality.

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