Rainwater Catchment Calculator
Calculate how much rainwater you can harvest here
How much rainwater can you collect?
When looking at rainwater tanks, understanding how much water you can collect and how much you’re using, will help provide a much clearer picture of what size tank you need.
In general, for each square metre of roof space, each 1 mm of rain will enable you to harvest 1 litre of rainwater. So, the two key pieces of information you need are to know your roof area and the average rainfall for your location.
Calculating average rainfall
To find the average rainfall for your location you can refer to your preferred weather station source or click here.
Increase rainwater harvesting
Why not use the roof of your tank to increase your rainwater collection?
If you are getting one of our round steel water tanks, these can be fitted with rain harvesting gutters, further increasing the available roof space collecting rainwater.
Rain Harvesting Calculator
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Rainwater tank options
Like to see what tanks we have available? Click your preferred option below to find out more.
Slimline water tanks
Modline / Rectangular water tanks
Round steel water tanks
Rural water tanks
Have questions about rainwater harvesting?
Whatever your water storage requirements, Puraflo is available to answer your questions and tailor a solution to match your needs.