2017 UN World Water Development Report (WWDR)

The 2017 edition of WWDR, the fourth in a series of annual, theme-oriented reports, is titled Wastewater: The Untapped Resource.

Main messages of WWDR

·      Globally, water demand is predicted to increase significantly over the coming decades. In addition to the agricultural sector, which is responsible
for 70% of water abstractions worldwide, large increases in water demand are predicted for industry and energy production. Accelerated urbanization and the expansion of municipal water supply and sanitation systems also contribute to the rising demand.

·      Climate change scenarios project an exacerbation of the spatial and temporal variations of water cycle dynamics, such that discrepancies between water supply and demand are becoming increasingly aggravated.

·      The frequency and severity of floods and droughts will likely change in many river basins worldwide. Droughts can have very significant socio-economic and environmental consequences. The crisis in Syria was, among other factors, triggered by a historic drought (2007–2010).

·      Two thirds of the world’s population currently live in areas that experience water scarcity for at least one month a year. About 500 million people live in areas where water consumption exceeds the locally renewable water resources by a factor of two.

·      The availability of water resources is also intrinsically linked to water quality, as the pollution of water sources may prohibit different types of uses. Increased discharges of untreated sewage, combined with agricultural runoff and inadequately treated wastewater from industry, have resulted in the degradation of water quality around the world. If current trends persist, water quality will continue to degrade over the coming decades, particularly in resource-poor countries in dry areas, further endangering human health and ecosystems, contributing to water scarcity and constraining sustainable economic development.

·      Improved wastewater management generates social, environmental and economic benefits, and is essential to achieving the 2030 Agenda for Sustainable Development.

Wastewater: An Untapped Resource

·      The quantity of wastewater produced and its overall pollution load are increasing worldwide. 


·      Over 80% of the world’s wastewater – and over 95% in some least developed countries – is released to the environment without treatment.


·      The release of untreated wastewater remains common practice, especially in developing countries, due to lack of infrastructure, technical and institutional capacity, and financing.

·      Pollution from untreated wastewater adversely effects on human health and the environment and reduces freshwater availability.

·      Treated wastewater is a reliable source of water that can be safely used to offset growing water scarcity. 


·      Wastewater can be a cost-effective and sustainable source of energy, nutrients and other recoverable by-products, with direct 


·      As an essential component of a circular economy, wastewater use and by-product recovery can generate new business opportunities while helping finance improved sanitation services. 


·      The costs of improved wastewater management are usually outweighed by benefits in terms of human health, socioeconomic development and environmental sustainability. 


·      Accelerating urbanisation and aging infrastructure provide opportunities for adopting alternative low-cost approaches to wastewater management tailored to meet specific local needs. 


·      Phosphorus recovery from wastewater is becoming an increasingly viable alternative to scarce and depleting mineral phosphorus reserves.


·      Actions to improve wastewater management fall under one of the ‘4 R’s’: reducing pollution at the source; removing contaminants from wastewater flows; reusing treated wastewater; and recovering useful by-products. 


·      Barriers to the use of reclaimed water and recovered by-products are often economic and regulatory, rather than technical. 


·      Overcoming negative public perceptions (i.e. the ‘yuck factor’) is critical to implementing water reuse schemes. 


·      Appropriate pricing of water from all sources to reflect its actual cost enables investments that can translate into affordable service delivery for all, including the poor.