Rainwater harvesting at home

This is a typical residential rainwater harvesting set up.
The system consists of ;
1. The catchment , that is the roof.
2. The first rain separator also called FRS to segregate the first few minutes of rain.
3. A sedimentation tank to settle any dust in the water. It also acts like a first rain separator.
4. A two chamber filter comprising of aggregates, silex and activated carbon.
5. An underground water storage tank to collect the water.
6. A recharge well to collect any excess water or overflow from the Storage tank. It also collects the surface run off.
Some of the salient features of this set up are;
A. A two chamber up-flow filter is used since the catchment has many plants and the water needs additional filter.
B. A sampling valve is given to collect water sample for purpose of testing.
C. Filter is designed in such a way that the filter can be back-washed after every rain.