4 links have been added on this idea.
  1. Take a look at this company that has invented a cutting-edge wastewater recycling system for residential buildings in the UK.

  2. San Francisco is at the forefront of wastewater recycling for both commercial and residential buildings.

  3. This Indian city plans to enforce mandatory greywater recycling in all new buildings.
    https://bangaloremirror.indiatimes.com/bangalore/others/new-homes-in-bengaluru-must-recycle-greywater/articleshow/115150480.cms