The Delhi Jal Board has advocated a rating system for water-using appliances similar to the one that is used to denote energy efficiency for an electrical appliance.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/jal-board-advocates-new-rating-system-water-appliances
[2] http://admin.indiaenvironmentportal.org.in/category/author/smriti-kak-ramachandran
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/hindu-new-delhi
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/delhi
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/delhi-jal-board-djb
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pricing
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/ganga
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/yamuna
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy-efficiency
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/mumbai
[11] http://admin.indiaenvironmentportal.org.in/category/thesaurus/bangalore-t
[12] http://admin.indiaenvironmentportal.org.in/category/thesaurus/hyderabad-t
[13] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-supply