Investing 0.16 percent of global GDP (US $198 billion) in the water sector could reduce water scarcity and halve the number of people without sustainable access to safe drinking water and basic sanitation in less than four years, stated a United Nations Environment Programme (UNEP)'s report.
According to the Green Economy Report, currently the failure to invest in water services and to collect, treat and re-use water efficiently, is exacerbating water shortages in many parts of the world and contributing to a situation where global demand for water could outstrip supply by as much as 40 percent within 20 years.
Hence, investing in sanitation and drinking water, strengthening local water supply systems, conserving ecosystems critical for water supply, and developing more effective policies can help avert the high social and economic costs resulting from inadequate water supplies.
The Green Economy Report shows that improvements in water productivity, as well as increases in supply (from new dams and desalination plants as well as more recycling) are expected to narrow this gap by about 40 percent, but the remaining 60 percent will have to come from infrastructure investment, water policy reform and the development of new technologies.
It observed that improving the efficiency and sustainability of water use is also vital if the world's increasing energy demands are to be met; as countries become wealthier and more populous, industrial demand for water is expected to increase.
Under the green investment scenario outlined in the Green Economy Report, global water use could be kept within sustainable limits and the Millennium Development Goal of reducing by half the proportion of the population without sustainable access to safe drinking water and basic sanitation, could be met by 2015. "With an annual investment of US $198 billion, or 0.16 percent of global GDP by 2030, water use could be made more efficient, enabling increased and sustainable agricultural, bio-fuel and industrial production," it added.