We have a storm water catchment system in our building with the pipes funnelling through our underground carpark.
Wouldn’t it be great to add a rainwater tank in the basement carpark and then use this to water our gardens?
Yes, it would be nice from a water efficiency perspective but have you considered the additional energy costs of pumping the water?
At Freesia gardens, we did the sums and it was a project which wasn’t worth proceeding with.
Water is still “cheap” compared with the rising energy costs which have doubled in the last 7 years.