Water and Land Use Change Study

The Water and Land Use Change (WatLUC) study addresses the challenges posed by land use and hydrologic change across south-western Victoria. Land use changed rapidly across this region during the late 1990s and the early years of the current decade. Although it has slowed in some sectors in recent years, the scale and nature of land use and vegetation change is so great that it has potential to transform the volume and quality of water moving through the region’s landscapes. This may have profound implications for the region’s water dependent ecosystems and for the way in which its water resources are managed.

The two major objectives of the WatLUC study were to:

  • Understand the dynamics of land use change in the region and develop some scenarios that reflect realistic land use change outcomes;
  • To assess the impacts of these scenarios on water movement through landscapes and on the availability and quality of water for consumptive and environmental uses.

To date, there have been two stages in the WatLUC study. The first stage developed methods for determining the hydrologic impacts of land use and land use change and applied them in five case study catchments. This document reports on stage 2, in which the methods developed in stage 1 were applied to both the Glenelg Hopkins and Corangamite Catchment Management Authority (CMA) regions. It reports the nature and scale of hydrologic change associated with land use change scenarios and discusses some of the implications for water resources and flow-related stress in river systems.

The WatLUC project is primarily concerned with a sub-set of the land uses practiced in south-west Victoria, they include:

  • Broadacre grazing with sheep and/or beef cattle
  • Dairying
  • Broadacre cropping
  • Urban and commercial land use
  • Viticulture
  • Rural residential land use
  • Plantation forestry using native hardwoods and Radiata pine
  • Nature conservation through restoration of indigenous vegetation on private or public land

Ten land use change scenarios, incorporating different mixes of these land uses, were developed for the study area. The scenarios were derived from current land use mapping, trends in agricultural land use and commodity production, industry consultation and regional natural resource management policy documents. The combination of land uses in 1990 and 2003 was common to all scenarios. Individual land use combinations were developed for each scenario for 2010, 2020 and 2030 and for all of the 66 sub-catchments defined for the study area.

Water and Land Use change study