Indian Politics & Policy Volume 1, Number 2, Fall 2018 | Page 114

Parameters of Successful Wastewater Reuse in Urban India
Closed-Loop or “Zero
Discharge” Cases
In Karnataka and Tamil Nadu, the
Pollution Control Boards are now
requiring industries, housing societies,
and five-star hotels to use recycled
wastewater for gardening, toilet flushing,
and industrial processes. 20 There
are only a few water recycling projects
in the country that can be considered
closed-loop or zero discharge. They
are interesting models and propose the
most dramatic shifts in the hydrosocial
cycle. They transform consumers into
producer–consumers and this has interesting
implications for governance
over wastewater management.
The two projects we introduce
as case studies are located in large institutional–business
complexes. One
is at the IIT in Chennai and the other
is in the Renaissance Hotel and Convention
Center in Mumbai. Both their
systems were developed to help solve
water-scarcity problems. The IIT needed
water for its sprawling campus at a
time when city provisions were running
very short. Engineering professors were
instrumental in getting the university
administration to invest in a state-ofthe-art
system to recycle wastewater
and re-engineer the entire campus for
dual plumbing. 21 With a population of
about 20,000, of which 9,000 are students,
9,000 are residents, and 2,000
constitute a floating population, the institute’s
one-day requirement is 2.8 mld
and the Chennai Metro Water and Sewage
Board supplies 1.2–1.8 mld of pure
water. The gap is bridged by treated
wastewater on site. Their STP provides
recycled water for toilet flushing in the
dormitories, for campus gardening, air
conditioning, and other building and
cleaning needs. The facility was built in
a phased manner, at a cost of about 20
crores (Krishna Chaitanya and Krishna
2017). During the drought of 2015, the
campus was able to function with very
little city water, using their own internal
resources through recycling. The
lead professor in this effort recently explained
to the Indian Express:
The IIT-M STP treats close to 30
lakh [3 million litres per day],
including 8 lakh litres [800,000
litres per day] of wastewater
generated by the IIT-M research
park. They send back 8 lakh litres
of treated water to the research
park for their utilization and 10
lakh litres is routed for flushing
and upkeep of greenery. So the
remaining 10–12 lakh litres is in
excess, which is being diverted
into ponds. Once those are full,
two groundwater recharge wells
are dug up, each having a capacity
of 0.5 MLD. This will replenish
the fresh water lake. Overall,
nothing is wasted. (Krishna
Chaitanya and Krishna 2017)
The second closed-loop system
is in the Renaissance Hotel and Conference
Center in Mumbai. The Manager
of the Engineering department
explains that they were first motivated
to upgrade and fully utilize their own
STP after water shortage affected their
ability to run the AC cooling towers for
three very large high-rise hotel buildings.
At that time, they had a smaller
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