Human Intervention at Tumbi Wetlands Bushcare 
How can we collect and use rain water?
Of course this will involve collection and some sort of storage.

There are devices on the market that make it easy to collect some of the rainwater from one of your household downpipes.
Water is still a scarce resource
You will need some space to place a storage tank, but again there is quite a variety available, from large conventional tanks to small makeshift ones illustrated.