Md. Firoj Alam
17 March 2015
“Water and Sustainable Development” is the
theme of the World Water Day 2015. The
theme of this years no doubt is very relevant and significant as the SDG
(Sustainable Development Goal) is going to be finalized at the end of the MDG
(Millennium Development Goal) this year.
There are many products and by-products of
development. Waste is one of the obvious by products of it. Without creating
waste, it is very difficult to make the development happening and continuing. In
the plain word we can say, “The more you get developed, the more you produce
waste”. Many countries, especially the countries which are doing rapid economic
growth are already in trouble to deal the waste created in their development
process. The developed countries has chosen to incinerate waste to get rid of
it but it pollutes air. They are actually internationalizing their own /local
problem, while the developing countries are using the waste mostly for
landfilling and pollutes their land, air and water at a time. In this article I
would like to shade a bit of light on the water pollution, particularly the
ground water pollution caused mostly by our improper waste management.
Water is one of our most important natural
resources which we have a plenty in quantity though it is poor in quality. This
is why we are living with abundance and scarcity of water at the same time. We
are spoiling our water knowingly and unknowingly every day. Neither ground
water, nor the surface water is spared from the contamination. The pollution of
surface water is very much visible to us and we often discuss about it. Contrarily,
the ground water on which we are depending fully for our daily consumption is
getting contaminated every day and it is remaining unnoticed to us generally.
One of the unnoticed contaminants of our
ground water is the municipality waste. Let me elaborate this area a bit. In
Bangladesh there is no well managed waste disposal system, let alone a complete
waste management for the towns. So far what the municipal authorities are doing
is just dumping the waste in an open place close to the towns which is often
situated very close to the localities. In professional language it is called
“non-sanitary landfill”. Examples are many of this in and around Dhaka city,
divisional and district towns.
The wastes in our country are mostly green
waste: bio degradable waste. However the share of hazardous and non-bio
degradable waste is also huge. As the numbers of population is very high and
the concentration of population is highest in our country in the world we
produce a huge amount of waste daily though the per capita waste is very low here
compare to the developed countries. The waste in the dumping sites produces a
lot of methane that contributes to the global warming. Global warming potentials (GWP) of methane
gas is 21 times higher than the carbon-di-oxide which contributes 12% of our
total greenhouse gas emission. I am leaving the methane emission issue here as
it is not an issue of my today’s discussion. Let’s come back to the ground
water pollution.
The non-sanitary landfill is very dangerous
because other than producing methane it produces a huge amount of liquid called
leachate. Leachate is just a soup of bacteria, chemical elements and particles
of heavy metals. This leachate percolates down to the ground water quickly and
travels far through the aquifer and contaminates our safe water which we are
extracting through the tube-wells and using for drinking and cooking. In
Bangladesh we sometimes test the arsenic in the ground water and we seldom look
into the other chemical and biological parameters. There is every possibility
of having heavy presence of chemical and biological pollutants in the ground
water where the dumping sites are!
Bangladesh is called a graveyard of
tube-wells. After identification of arsenic in the ground water many tube-wells
were abandoned immediately by the users. The pumps of the tube-wells have been
taken away and left the well redundant. These wells are just uncapped, open I
would say rather. The opened tube-wells have the every possibility to
contaminate our precious ground water as contaminant can easily pass to the
ground through the boreholes. Many of the boreholes are located inside the
industrial premises with a high likelihood of contaminating the ground water
with chemical and bio-logical effluents of the industries.
We the users are just unaware about the risk
of contamination that may occur through the redundant tube-wells. We simply leave
the non-functioning tube-wells uncapped and allow the pollutants to reach up to
the ground water. As per an estimation, there are about 10 million tube-wells
in Bangladesh. The number of the redundant tube-wells is very high, we can assume
from this data.
Neither in the urban area nor in the rural area
we have appropriate faecal sludge management system. The sewerage lines of the
municipalities in most cases are opened onto the rivers or waterbodies while
the open toilets are contaminating surface water years after years. In last three decades we have achieved a good
coverage in terms of use of improved latrines. Different sources show that
about 80% of our population is now using latrine. Bangladesh has done a better progress than
many countries in the world in this regard. We are proud of it. However, most
of these latrines are just a pit latrine in type. It is constructed by the
people using very basic technology. It
is true that it can confine the faecal matter in a fixed place and can prevent
the pathogens to come out in the open environment but it has also created a
high risk of contaminating the ground water especially in those areas where
water table is high. I know for sure from a study done in an island of Bay of Bengal
in Bangladesh that pathogens escaping from the toilets pit had contaminated
total source of ground water there. Now it is really a time to teach the people
how to seal the toilet pits to protect the ground water from the pathogens of
the faeces.
Our ground water is already in a severe stress
as the natural pollutant like arsenic, salinity and iron are found in many
areas. The over extraction of ground water is causing the depletion of aquifer
in the rural and urban areas including Dhaka city. Our surface water is already
so contaminated that it is almost irrecoverable through treatment. If we go on
contaminating our water in such a pace, we will have to import safe water from
India, Nepal, Bhutan and Myanmar in future to meet our daily demand. I am sure,
none of us are ready for that!
Md. Firoj Alam is a Water Sanitation
and Hygiene Officer of a UN agency in Bangladesh.
