India, Oct. 21 -- The Swachh Bharat Mission turned 12 earlier this month. After constructing household toilets, to close the sanitation loop, the mission's Open-Defecation-Free (ODF)++ protocol of 2018 asked cities to ensure no untreated sewage or faecal sludge was dumped into drains, water bodies or open land. The Water+ protocol of 2019 set a higher bar, requiring all used water from homes and businesses to be treated and reused where possible.

But the mission funds used-water management only in towns with fewer than one lakh people. Larger cities were left to AMRUT and Namami Gange. The 16th Finance Commission moved to close part of this gap, allocating Rs.56,100 crore under a Special Infrastructure Grant for 22 cities with population...