Oral Presentation NCGRT/IAH Australasian Groundwater Conference 2019

A collaborative study combining contemporary hydrogeological methods with traditional knowledge to understand living water in the Great Sandy Desert (228)

Steven J. Bolton 1 2 , Peter Murray 3 , Sarah A. Bourke 2
  1. Rockwater Pty Ltd, Jolimont, WA, Australia
  2. School of Earth Sciences, University of Western Australia, Crawley, WA, Australia
  3. Ngurrara Rangers, Yanunijarra Aboriginal Corporation, Fitzroy Crossing, WA, Australia

The traditional water sources (Jila and Jumu) of the Great Sandy Desert are of significant cultural value to the traditional owners, the Ngurrara people. Prior to European settlement these were the only source of water for the people of the Great Sandy Desert and they are integral to Ngurrara culture. The Ngurrara people have long-term observations of the surface waters’ seasonally-changing taste (salinity) and water levels. This collaborative research project was established to increase our understanding of these valuable water features and support the development and implementation of water resource monitoring and management.A hydrogeological review of aquifers and groundwater-surface water (GW-SW) interactions was conducted for five culturally-significant water bodies: Wili Jila, Kurnajarti Jila, Puluwala Jila Lumpu Lumpu Jila and Lake Pirnini Jumu. This assessment included monitoring bore installation and measurement of water levels and major ion composition over a 15 month period. The Jila and Jumu of the Great Sandy Desert are diverse in hydrogeological setting and water chemistry. Water balance data show rainfall is insufficient to maintain the water levels observed at permanent surface water expressions (Jila) throughout the year. Surface water assets that are disconnected from underling aquifers (Jumu) only provide temporary sources of water prior to evaporation.  Characterisation of the groundwater shows both NaHCO3 are Na-Cl type waters occur in the project area. Regional groundwater levels suggest groundwater flows from the south and north of the project area toward a topographically low, terminal basin. However hydrogeochemical data shows groundwater to be least saline at the lowest elevation of the project area, where it is expected to be the most saline. Bringing together traditional ecological knowledge and contemporary hydrogeological methods, this study has provided an updated understanding of the hydrogeological systems that have been relied upon by the Ngurrara people. This renewed understanding has been applied to the development of a monitoring and management system that seeks to preserve these important water bodies under the concept of Living Water.