Thank you for your question!
Submersible pumps are actually in use in some places in Cape York – our interactive walk through of a water supply system (found in Resources – Interactive: Explore CfAT project examples) includes a submersible pump in that design.
However, as you’ve identified, portable fire fighting pumps are also being consistently used across Cape York due to their availability, cost and ease of use. A submersible pump system is more expensive to install and can require technical expertise in implementing the system, as well as making sure it is resistant to extreme weather events. The repair and replacement of a submersible pump is more complex than that of a mobile fire fighting pump, the latter being easier and cheaper to implement, repair or replace.
I’ve linked below a previous question in this discussion forum which gives some more insight into portable fire fighting pumps.
About Increasing natural disaster resilience of riverbank pump systems
I hope this is helpful, please reach out if you have any more questions!