Dampier Peninsula groundwater investigation

This groundwater investigation aimed to improve our understanding of the Dampier Peninsula’s groundwater resources and how they support groundwater-dependent ecosystems north and east of Broome.

We support community and economic development opportunities and regional growth by making water information publicly available. Water users and managers can use the information we gained from this project to support water licence applications, and we will use it to manage groundwater resources.

We conducted this groundwater investigation as part of the statewide Royalties for Regions Regional Water Availability program. It was made possible through strong working relationships with traditional owners and other groundwater users.

What we did during the investigation

During the study we:

  • collected 4,326 square kilometres of aerial electromagnetic data
  • constructed 35 bores
  • undertook ecological fieldwork at 35 sites
  • sampled water from surface waterbodies, rain, aquifers, soil and plant tissue.  

Key findings and how we are using the information

We now have a good understanding of the physical characteristics of the Broome Sandstone aquifer, including depth to groundwater, saturated thickness, recharge rates, location of the seawater interface and groundwater-dependent ecosystems. We have synthesised this information to identify areas where groundwater development might have fewer constraints and created a water opportunities ‘map’.

Key findings from the project include:

  • More information about the Broome Sandstone aquifer, which:
    • covers the whole study area and is fresh and generally unconfined
    • is typically within 20 metres of the surface near the coast and more than 80 metres below the surface over much of its inland extent
    • is around 100 metres thick in the centre of the peninsula, thickens to more than 500 metres in the north and thins where the confining layer is present
    • has estimated median recharge rates between 5 and 16 mm per year.
  • Identification of a new aquifer on the Dampier Peninsula underneath the Broome Sandstone aquifer and confining layer, which:
    • is fresh, has subartesian pressure where we drilled and is possibly artesian further south where the aquifer becomes shallower
    • spans over 930 square kilometres and is generally over 100 metres thick (according to aerial electromagnetic data).
  • The seawater interface is generally close to the coast but is up to 11 km inland around Willie Creek.

Where to get more details

Our Managing groundwater resources on the Dampier Peninsula fact sheet outlines new information about the physical characteristics of the Broome Sandstone aquifer, including depth to groundwater, saturated thickness, recharge, location of the seawater interface, the extent of the newly defined confined aquifer and the distribution of groundwater-dependent ecosystems, along with the water opportunities map.

The Groundwater-dependent ecosystems of the Dampier Peninsula report presents the findings of the ecological investigations, specifically the identification, characterisation and mapping of groundwater-dependent ecosystems.

You can request detailed information on the hydrogeological investigation by emailing groundwater.info@dwer.wa.gov.au.

Go to our Water Information Reporting portal to access data from the monitoring bores installed during the investigation.

Read more about our groundwater investigations by region across Western Australia.

Page reviewed 26 July 2022