Unfolding Narratives

houses and offices reveal concrete lumberyards. Converting these
areas into green roof can be simple and inexpensive. It only needs
inputs from the expertise of building and landscape designers
during the planning process. It is next to impossible to create ponds
or water bodies in crowded urban spaces so helping the water to
rise can be a service that can be helpful as well. Constructing a
green roof is not an indulgence but should be taken as a
commitment to rainwater harvesting that may not have been
planned or desired by the building’s owners. However, a green
roof that uses municipal water to create lush greenery is no good at
all. But such roofs naturally capture and absorb normal rainfall
quantities reducing the amount of storm water discharged into
municipal sewer systems. In dry areas these might appear of much
use but wherever there is reasonable, it can be a very useful factor.
IMPORTANCE OF RAINWATER HARVESTING
Commercial water harvesting systems will become more popular if
business establishments and commercial building owners are made
aware of its benefits in rupee terms. Reduced usage of municipal
water translates into substantial amounts of finances with many
secondary benefits. It is also legally mandated in construction
activity.
In times when sustainability is used as a marketing gimmick at
times, it is commercially sensible to include these systems in any
construction for long term cost savings that come about with
commercial rainwater harvesting systems.
In fact rainwater harvesting and grey water reuse should be
mentioned in the same breath. In USA, the National Sanitation
Foundation has set a standard and certification process for
commercial greywater harvesting systems. Greywater is the water
used extensively and often mindlessly in sinks, showers, toilets and
for general irrigation of lawns in commercial spaces. While USA
may have established clear and realistic guidelines to define proper
quality criteria for greywater reuse treatment systems, India is still
struggling to create the need and drive for such measures.
Not that there aren’t enough systems and guidelines in place.
Commercial buildings and multi storey apartments blocks can befit
hugely and architects and building owners can easily incorporate
this in projects. Green Building rules, formalised by Indian Green
Building Council, will result in the practice of recycling on-site
water for non-potable uses and will eventually become popular in
commercial properties and multi-unit housing.
THE TECHNOLOGY IS NOT ROCKET SCIENCE
Rainwater harvesting has a demonstrable payback and many
installations will pay for themselves in just a few years. On larger
commercial applications it can be possible to achieve quantity
savings on mains water in the order of 35-40% with commensurate
savings on commercial water rates.
Rainwater harvesting is now mandatory in India for hotels, malls
and hospitals in major urban areas.
The government has decided to make rainwater harvesting
compulsory in urban areas considering the increasing population
and burden on water supply. Low rainfall situations and drying
ground water levels are main challenges in urban as well as rural
areas to keep sufficient water supply since rain water harvesting is
a sustainable way of water conservation. Such water can be used
throughout the year for all basic needs after filtration and UV
disinfection.
It is not all about high technology since a simple roof water
collection system, a pump and a storage tank makes a basic
rainwater harvesting system. A pump is needed to circulate water
between filter, storage tank and the building and UV disinfection
systems like ALFAA UV are needed to destroy microorganisms to
make water safe for drinking. However there are other ways for
roof top rainwater harvesting through recharge pits, trenches, tube
and recharge wells as well. By connecting with government, both
at central and state levels, the building and construction industry
can play a major role in resolving urban water woes.
Architecture Update March 2016 21