Diffuse pollution,
the invisible threat
Think pollution, and clogged streams and landfills come to mind. But
there are invisible, less obvious culprits that poison rivers and water
sources throughout the world.
By Kim Kemp
W
What is diffuse pollution?
Who better to answer the question
than Brian D’Arcy, an independent
environmental consultant who
has worked for many years in
environmental regulation and water
pollution control. For about the past
15 years, his focus of involvement
has been diffuse pollution and he is a
recognised authority on the subject.
“Diffuse pollution is the release of
potential pollutants from a range of
activities that, individually, may have
no effect on the water environment but,
at the scale of a catchment, can have
a significant impact. Problems occur
in both rural and urban environments
and examples include urban storm
water runoff into rivers; sulphur
dioxide emissions to the air from fossil
fuel combustion causing acid rain
and acidification of lakes; and so too,
nutrients and pesticides washing off
vast tracks of farmland into surface
water or, percolating down through the
soil, into the groundwater,” he explains.
The thing about diffuse pollution is
that it is generally unintentional, he
says, and adds: “For diffuse pollution,
no-one gets out of bed to make a
discharge to pollute the environment.
You wash your car, you plough the
hile the Organization for
Economic Cooperation
and Development (OECD)
countries can boast decades
of regulation and investment in
wastewater treatment plants,
producing gains for economies,
human health, environment, and social
values, the emerging and developing
economies are yet to make such
headway and there are still major
problems from water pollution.
Nestled in amongst all the obvious
pollution s ources are invisible and
indirect sources of water pollution,
known as ‘diffuse pollution’.
The use of pesticides in agriculture is one of the primary causes of diffuse pollution in groundwater and waterways generally.
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Water Sewage & Effluent November/December 2017