The trilemma of population growth, economic growth and environmental sustainability
Whenever resources become scarce, the share available to the poor gets even smaller. In some developing countries, up to 98% of available water is fully allocated. The bulk of the allocation is to agriculture and industrial users, leaving little for human consumption. As population growth breaches the 9 billion mark in 2050, current projections point towards increase in Energy (+23%), Water (+55%), and Food (98%) demand. Urban population globally is expected to increase by up to 70% in 2050. The UN estimates that the amount of wastewater produced annually is about 1 500 km3. This is six times more water than exists in all the rivers of the world. This explosion in urban population, coupled with the drive for economic growth, will certainly put more pressure on the environment, including water resources. The impact of these developments on the poor and under-serviced will be tremendous. There is therefore, need to decouple population and economic growth from environmental degradation in order to lessen the burden on the poor.
My work in the Sub-Saharan region involves treatment of water and wastewater for drinking, re-use or disposal. I am constantly exposed to the impacts of pollution on the environment and communities emanating from industry as well as municipalities. By definition, sustainability is “meeting the needs of the present without compromising the ability of future generations to meet theirs”. If the status quo falls short of even meeting the needs of the present day generation, particularly in Sub-Saharan Africa, how then can we secure the three pillars of sustainability (people, planet and profits) for the next generation?
For industries like mining, the major deciding factors to install water treatment plants are capital and operational expenditure. On the other hand, municipalities are encumbered by lack of revenue generation from water sales, rates and taxes. The lack of wastewater treatment capacity at municipal level invariably implies pollution of freshwater resources by untreated sewage. This is exacerbated by the prevalence of emerging pollutants in water systems, many of which cannot be adequately removed by currently installed plants. Furthermore, failure to treat industrial effluents like Acid Rock Drainage (ARD) by mines, which are mostly located in poor communities, invariably leads to pollution of freshwater resources by metal laden effluents. These challenges directly increase water poverty among the poor, posing a significant barrier to the achievement of the very first SDG.
One of the ways to decouple population and economic growth from environmental degradation is to develop and implement self-sustaining water treatment technologies. In addition to augmenting the dwindling freshwater resources, this will turn industrial effluents and municipal wastewaters into valuable resources. Recovery of energy from waste is nothing new; however, higher efficiencies are required for the business case to be widely applicable. One the other hand, ARD often comes rich in metals which can be recovered and processed to highly lucrative products if technology is available.
The growth in population and economies, coupled with affluence, has led to increased energy use. This means that there is ever increasing need for water treatment technologies to be energy efficient to ensure sustainability. However, if the cost of treatment is inherently high like in desalination, recovering valuable by-products will off-set the operational costs. A case in point, in South Africa where I live, metalliferous ARD constitutes 3% of the total annual volume. Valuable by-products can be recovered in the process of treatment of ARD and reduce the cost of treatment in addition to diverting toxic sludges from landfill sites (which are often located close poor communities and freshwater sources).
Pertinent Questions
· How will population growth affect water supply complexity?
· Is decentralization a sustainable solution?
· In light of accelerated rural to urban migration, how can urban informal settlements be better serviced?
· How can we leverage technology to educate the population about water and sanitation?
· What incentives can be put in place to stimulate private sector investment in provision of water and sanitation services, particularly to the poor who do not have buying power?
· How can the agricultural sector contribute towards mitigation of water scarcity and waste?
· In addition to existing water efficient agricultural practices, how else can the industry reduce water consumption?
