Petition UK Planning Change – All new build houses to have Grey Water / rain water harvesting systems.

With much of the UK suffering in drought conditions, surely it is time we took responsibility for how much water we use and what we use it for. For too long expensive white drinking water has been wasted, being used to flush toilets and water gardens. Surely All new build houses should incorporate full rainwater harvesting and recycling of Grey Water.
Statistics show that this should reduce the usage of fresh water by up to 50%
So this would be a win win situation for home owners as well, as water bills should be reduced.
If Grants were made available for retrofitting of these systems, the existing water supply system would be more than adequate as demand becomes static and then decreases. Saving the water industry billions, keeping bills static and helping the environment.