Fresh water scarcity will be the problem of the
century affecting every inhabitant on this planet. It is a result of major
population spikes, improved standards of living, and over consumption from the
expanding first world nations. Less than 0.1% of the world’s water supply is
fresh water on earth which is easily accessible. The rest consists of
surrounding oceans and water sources that are difficult to obtain economically.
In a technical sense, the amount of water is not necessarily the problem. The distribution
on a global scale is. If current trends continue from the last few decades
humanity will be facing a water crisis by 2030.
The increasing risk of climate change, droughts, floods, and an increased
pollution all play roles in the water crisis.
a large scale average, a majority of the world lacks proper infrastructure to
deal with wastewater effectively. A majority of waste water facilities
discharge its effluent into surrounding bodies of water which leads to negative
environmental impacts downstream. The untreated wastewater is a majority of
developing countries is used for agriculture which is can lead to contaminated
food sources and disease for the population. A proper water reuse strategy needs
to be established in developed and developing nations to tackle the water
scarcity problem before it is too late. A suggested solution to this concern is
the decentralization of water treatment facilities which have been proved to
have both economic and environmental benefits compared to its counter partner
of centralized systems.
waste treatment system (DEWATS) by definition is to convey, treat and dispose or reuse municipal and industrial wastewater from small
communities, buildings and dwellings in remote areas, individual public or
private properties. The key
difference between the centralization is its proximity to the source of
generation. It allows for smaller networks of piping systems with the
simplicity to separate different water types like black, grey, and urine. It
also allows for the ability to use simple mechanisms such as gravity sewer
systems to transport the water. The effluent would fluctuate depending on the
rainfall and use.
In new developing areas it becomes available
alternative to its conventional standardized system. The ability to upgrade
existing cities and municipalities exists which lead to hybrid system
mechanics. They have an underlying issue as being seen as a temporary solutions
but city infrastructure including drainage is always taken into account primarily
before the development of permanent residencies. Also, the economic burden of a
centralized system affects taxpayers of all sorts. It is highly expensive with
little physical profit margins to in an industry like water.
A DEWATS utilizes low-maintenance systems
that include septic tanks mainly for domestic use, waste stabilization ponds
(facultative/maturation lagoons), and constructed wetlands. The basic technical
treatment process includes a primary treatment which a sedimentation and
floatation process occurs. Secondly, an anaerobic treatment in a fixed-bed
reactor occurs usually by baffled upstream reactors or anaerobic filters. Tertiary,
an aerobic treatment t in sub-surface flow filters is done followed by a
The advantages for a system like
this ultimately outweigh the disadvantages. It allows for the ability to treat
up to 1000m3 of waste water flow daily, which could handle significant
areas either residencies or by industry.
Also, the modular design technique allows for the system to be easily
divided into smaller working parts which can work independently or cohesively. The
ability to deal with the inflow volumes is also a major benefit to a DEWATS
system. It allows the equipment to not be overworked and allows the room for
reliability and longevity with a little maintenance. The low cost and
maintenance also are prime selling factors to this technology. It allows for minimum
training or upkeep so anyone have the ability to install and facilitate a
system. Although there are many advantages a number of disadvantages exist too.
It requires a large area of land which
in some densely concentrated areas would not be feasible. Also in countries
that land space is constricted and high populations are only rising making this
option unattainable. Also, the ability for wetland treatment is only a viable
if the this sort of land exists around a major population. There have also not
been definitive specifications on different on how climate conditions disrupt
all types of waster waters.
In the city of Bangalore, India, the
population is over ten million making it the fifth most populous city in all of
India. It is located in the Karnataka state and is spread out over 800 km2.
It has been dealing with widespread water problems for over 25 years. The entire
cities natural water source has since dried up and government mandate has taken
president. The Supply and Sewerage Board (BWSSB) has been commanded to pump
over 1.2 billion liters of water per day from the Kaveri River which is all
utilized for domestic consumption. The city is dealing with drastic water
shortages and the centralized system cannot handle the capacity of volume. It
has insufficient drainage networks which do not allow for proper transportation
purposes. The remaining untreated wastewater is then released into streams,
lakes, and other bodies of water which leads to massive pollution problems in
an around the country. It has been known to kill fish and other wide life. In
2004 the Karnataka State issues a zero-liquid discharge order. This in tale
means that all areas that lack proper drainage networks must install a
permanent on-site regulatory treatment plant system and reuse all its water.
The solution to this problem was to install DEWATS all around the city to help
deal with its crisis. This policy was seen as strict in nature but necessary for
predicament surrounding this town and its people.
Nepal has also used the DEWATS to
tackle water problems similar to India. The treatment facility was used at the
Dhulikhel Hosptal which is non-profit, non-government run. It was