Space sensors help solve African water shortages
Whereas most Europeans live in towns and cities, the people of poorer countries usually live in the countryside. But this situation is changing rapidly. In recent years, developing countries such as Zambia have been transformed by people pouring into urban areas.
Zambia already has one of the highest urban populations in southern Africa. About one third of the country’s 11 million people are now living in towns and cities. This inflow has been so rapid that services such as water supply and sanitation have not been able to keep pace.
In an effort to keep track of the explosion in city dwellers and to plan for problems such as shortage of water, the Zambian authorities are turning to images from ESA’s Envisat spacecraft. Satellite-based maps of the Kafue River Basin, home to over half the country’s population, have been produced by the ESA-funded IWAREMA (Integrated Water Resource management for Zambia) project.
Local authorities can now study the expansion of urban areas and its effects on nearby forest and agricultural areas. It is also possible to calculate the risk of soil erosion and give early flood warnings by monitoring changes in surface water. "The results of the IWAREMA project can be used to protect Zambia’s ecosystems particularly in the Kafue flats where wildlife, agricultural activities, fisheries and tourism compete for regulated water resources," said Jack Nkhoma of Zambia’s Department of Water Affairs. IWAREMA is one of many projects initiated under ESA’s TIGER initiative, launched in 2002 to assist local authorities across the continent with water management.