Quantifying Climate and Management Impacts on Watertables and Soil Salinity (Summary)

Abstract

This report describes the development of a surface-groundwater interaction model for the Murrumbidgee Irrigation Area (MIA), situated in New South Wales, about 600 km west of Sydney and 900 km east of Adelaide. The MIA includes the town of Griffith and Leeton, and the study area covers the boundaries of 375250, 6150500 and 460000, 6230000 in UTM coordinate system shown in Figure E-1. On July 13, 1912 the irrigation scheme was opened bringing water to the area from storages (Burrinjuck dam – 1026 GL and Blowering dam – 1628 GL) through rivers and supply channels, using gravity as the means to manage water flow. Rice growing started in 1924 with its rapid development during 1970-80s. The total area for the MIA is 230,222 ha having dominant land use of rice with more than 32,000 ha in year 2000. Water use by crops is presented in Table E-1. The rising watertable and salinisation have threatened the viability of the MIA and this work is part of management strategies to ensure the sustainability of the area.