Application of GIS for Mapping Rainwater-Harvesting Potential: Case Study Wollert, Victoria

Water is a basic normal asset for supporting the condition of life. Accessible water assets are feeling the squeeze because of expanding demand. Soon wa-ter, which we have depended upon to be accessible and an unconditional present of nature will turn into a rare product. Protection and conservation of water assets are desperately required. In many parts of Victoria, water supply to communities is limited. Rainwater harvesting systems can provide water at or near the point of demand. The systems can be owner and utility operated and managed. Rainwater collected using existing structures, i.e. rooftops, parking lots, playgrounds, parks, ponds, floodplains etc., has few negative en-vironmental impacts compared to other technologies for water resources de-velopment. Rainwater is relatively clean and the quality is usually acceptable for many purposes with little or even no treatment. The physical and chemi-cal properties of rainwater are usually superior to sources of groundwater that may have been subjected to contamination. The present study was intended to measure the rooftop rainwater harvesting potential using GIS techniques. The GIS examination utilized in this investigation was basically an efficient assess-ment of rooftop water collecting in the chose Wollert which is a suburb in Melbourne, Victoria. With the use of GIS it was conceivable to appraise the ag-gregate sum of water harvestable at the household level. It is very tedious work to assess the catchments available for rooftop rainwater harvesting. Here the roof surfaces are the catchments and GIS is employed to calculate the area of various types of roofs and their potential for planning for the area under study. As a result Eucalypt Estate Wollert has huge potential and can make above 179.11 litres water available per person per day throughout the year.