Sanitation and Wastewater Atlas of Africa

Wastewater in the water cycle

MUNICIPAL WATER

Agriculture

Water Treatment Plant

Wastewater Treatment Plant Fit-for-purpose

Desalination

Residential Commercial Institutional

Industrial

Recreational

Suface water

OCEAN

GROUNDWATER

Natural water cycle Groundwater flow

Raw water source Treated water

Treated wastewater Untreated wastewater

Agricultural runoff Urban runoff

GRID-Arendal/Studio Atlantis

Source: WWAP, 2017.

Figure 1.16 . Wastewater in the water cycle

worsen the situation, resulting in an increase in environmental and health-related problems.

and the income level of the country (WWAP 2017). Treatment capacity in 2012 was reported to be 70 per cent of the generated wastewater in high-income countries, compared to only 8 per cent in low-income countries (WWAP 2017). The consequence of such practices include increased disease burden as well as significant damage

to key ecosystems. Studies have also revealed that contamination from these streams usually finds its way into freshwater resources, resulting in increased levels of eutrophication and loss of some ecosystem services. Wastewater can also easily pollute groundwater due to the percolation process, as shown by Figure 1.16.

The WWDR stated that only 20 per cent of globally produced wastewater was receiving adequate treatment in 2012, adding that there seems to be a correlation between the treatment capacity

Treated wastewater can be used for irrigation and replenishment of groundwater, among other uses

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SANITATION AND WASTEWATER ATLAS OF AFRICA