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| Clean, abundant water is an important driver of economic growth, social stability and ecosystem health. |
Water pollution
is an important sustainability risk due to its impact on human health and the
environment. Importantly, water pollution also reduces available water
resources, at times rendering them unusable for their intended purpose. Water scarcity can
have serious impacts, and the prevention of water pollution should therefore be
a salient aspect of any national water security strategy, to be viewed within
an integrated framework that includes infrastructure development (dams, purification
plants, transfer pipelines etc.) and water conservation.
From the policy
and regulatory perspective, the water pollution issue is complex and requires a
multidisciplinary approach for its appropriate management. Diffuse pollution,
such as that caused by runoff from industrial sites, is particularly difficult
to measure, control and regulate. The many different modes of transport of
pollutants also makes this issue one which can fall within the ambit of different regulatory
bodies, increasing the challenges associated with its management. For example, problems around air
quality and solid waste management can ultimately result in water pollution
problems. In South Africa, the integration of national departments to yield a single Department of Water and Environmental Affairs can be considered to be an important first step in removing some of the structural impediments to the systems approach that is so essential in dealing with matters of water pollution at the policy level. This theme of integration carries through to the
micro level, and polluters themselves also require cross-functional
approaches if they are to get to grips with the water pollution issue
holistically.
Industry is but
one of a number of economic sectors which contribute to surface and groundwater
pollution. The impact of individual industrial sub-sectors varies markedly, and
it would be folly to tar all industries with the same brush in terms of their
water pollution profiles. Some industries have well-documented pollution
footprints, and are known to be riskier than others (for example the metals industry, where some players could pollute the environment with heavy metals or even hexavalent
chromium discharges, or the pulp and paper industry, which is know for its potential in terms of persistent organic pollutants
(POP’s), to name just two). However, seemingly innocuous discharges take
on a new significance when pollution life-cycles are considered. For example,
nutrient discharges from food processing could lead to algal blooms, some of
which could lead to the presence of carcinogenic cyanotoxins that could
ultimately find their way into drinking water. High organic loads could also
generate carcinogenic trihalomethanes during water purification. It is therefore vital for polluters to take a systems view of pollution, and to consider the downstream impacts of their activities in terms of how pollutants interact with the environment. These are the
types of risks that are generally not reflected in instruments such as the effluent discharge specifications industries are typically
expected to comply with. Compliance
therefore does not equate to sustainability, particularly in poorly regulated or
developing environments.
The implication for industrial players who truly wish to become sustainable is that they need to take a high level of organisational responsibility in dealing with water pollution. Holistic
and ongoing assessment of water pollution risks is essential. This assessment should comprise a review of
known industry-specific water pollution risks, detailed analysis of the various
pollution pathways through which contaminants reach receiving surface and
groundwater, a life-cycle assessment that considers the environmental, social
and economic impacts of individual pollutants, and the status of potentially affected catchments. The only way to carry out this assessment
effectively is to examine operations at the process level, identifying and characterising each individual pollution source. The mode of transport of the pollutants must be considered i.e.
are they emitted to the environment through a point discharge, through diffuse
runoff, via air pollution which finds its way into surface water resources,
through solid waste from which pollutants are leached into groundwater etc.
Every industrial site and each step in the value chain has unique pollution pathways with impacts determined by the nature
of the pollution and the status of the receiving environment in terms of its
assimilative capacity.
Site-specific
impacts are where control can be exercised most directly, and the most
effective mitigation strategy is to attack problems at source, using a
philosophy such as Cleaner Production, for example. From a product life-cycle
perspective, water pollution impacts can be mitigated by using alternative raw
materials, the careful consideration of product characteristics and packaging
and product disposal/recycling. This can become quite challenging, since the
effluents produced by many recycling processes can be hazardous, and while
recycling is generally considered to be positive from a resource efficiency
perspective, with easily measured financial benefits, the water pollution
impacts can be quite a different matter. In much the same way as effluents should
not be forgotten once they have been disposed of to drain, responsibilities
regarding water pollution do not end once products have been sold.
I’ve tried to
show in this post that this is a complex issue that has to receive focus in any
sustainability strategy. It is an issue that is difficult to police, and it is therefore
incumbent upon polluters to take responsibility for their impacts rather than
to have a compliance mindset that leaves water resource protection solely
in the hands of regulators. Lastly, if you view the ongoing management of water
pollution only as a cost, think again. Resource efficiency at source is one of the
most effective preventive strategies, and translates into direct material usage savings
as well as reduced costs of operation for water treatment plants where
end-of-pipe approaches are unavoidable. In some circumstances it is possible to generate revenues from the recovery of materials that would otherwise become a source of pollution, and there are also a growing number of clean waste-to-energy solutions making their way onto the market. As with all sustainability issues, water pollution should not be viewed in isolation, as this just leads to missed opportunities.
Copyright ©
2013, Craig van Wyk, all rights reserved
