The Pilbara is an arid region with an annual rainfall of between 200 mm and 350 mm, which is highly variable and dominated by tropical cyclones. Severe droughts and major floods may occur at close intervals, highlighting the need to secure water supply for the worst case and not scenarios based on the average rainfall for the area.
The region is experiencing significant growth. Some of the region’s public water supplies, particularly at coastal ports and towns need to be increased to meet the projected demand and improve security of supply.
The environment, social and cultural water issues are considered in water planning and future management of water in the Pilbara.
The Department of Water completed a program of investigation in this area that was part funded by the Australian Government’s $12.9 billion Water for the Future initiative.
What were the outcomes of the projects?
The final report – Water for the future – Statutory Water Planning for the Pilbara summarises the implementation and findings of the project. The most significant findings and management implications for the project areas were:
- Results from assessment of existing and potential water sources to augment Pilbara towns will improve the security of supply and extend the range of options for developing sustainable water supplies for towns and cities in the region.
- Sustainable level of extraction set for the Millstream aquifer will protect the culturally and nationally significant wetlands of the Millstream Chichester National Park
- Investigation of groundwater dependent ecosystems and cultural values will allow the consideration of these in-situ values in the allocation limit setting process. Specific objectives and rules to minimise or manage impacts on in situ values are being developed using the outcomes of ecological and cultural investigation and assessment projects.
Through this project we have also:
- assessed and reviewed Pilbara coastal alluvial aquifers
- completed modelling for the Millstream aquifer
- completed hydrogeological modelling and assessment of the West Canning Basin
- completed identification and assessment of groundwater dependent ecosystems
- completed Cultural water values studies
- established environmental reference sites
- completed the first phase of the East Pilbara water study
- developed a bore and mining report database
- developed a source and scheme infrastructure planning tool
What were the products generated through the project?
The following are reports completed and published:
- Interpretation of Airborne electromagnetic, magnetic and Falcon gravity gradiometer data, summary report
- Pilbara region, Western Australia TEMPEST – Geophysical survey – Acquisition and Processing Report, July 2009
- De Grey and Yule – Falcon Airborne gravity gradiometer and magnetic geophysical survey, 2009
- Development of a subregional scale numerical groundwater model of the Lower Yule Catchment, June 2010
- Lower De Grey Groundwater Model
- Lower Robe River Groundwater Model, June 2010
- Millstream Model Recalibration, Nov 2009
- Radio carbon age dating groundwater of the West Canning Basin Western Australia, March 2009
- West Canning Basin Model Design report, May 2009
- Determining the age of groundwater in the recharge zone and north-eastern section of the West Canning Basin Western Australia, April 2010
- West Canning Basin Modelling project, May 2010
- Long term Ecological research on a Pilbara River system, June 2009
- Fishes in groundwater dependant pools of the Fortescue and Yule Rivers; Pilbara, Western Australia, Sept 2009
- Conservation Status and habitat associations of Aquatic Invertebrates in Pilbara, Western Australia, Sept 2009.
- Lower De Grey: Ecological Values and issues
- Millstream Status report
- Groundwater dependent ecosystems for Millstream: ecological values and issues
- Lower Fortescue River – Ecological values and issues
- Determining Water level ranges of Pilbara riparian species
- Lower Robe River – ecological values and issues
- Millstream aquifer – determination of a long term sustainable yield and long term reliable allocation
- Yule River – ecological values and issues
We also produced the following unpublished reports. They include highly technical reports, chemical analysis results; bore drilling data and internal DoW policies.
- LiDar Metada Statement
- Pilbara River Pool project – progress report
- Pool mapping – Metadata statement
- Vegetation monitoring Yule bore field area
- Pilbara Water resource – capture of backlogged bore and mining reports
- East Pilbara Groundwater review (summary report)
Members of the public who are interested to access information within the reports are invited to contact the Department of Water Library on 63646425. Where reports contain confidential information, the department will provide a summary report upon request by the public.
How will the information be used?
Information will directly support improvements to future management of the resources. It will make a substantial contribution to a water allocation plan. A combination of robust science and information from stakeholders and the community about economic, environmental, social and cultural water issues will be used to prepare the water allocation plan for the Pilbara. The plan will help secure water for the Pilbara area, in line with the requirements of the National Water Initiative.