Project uses satellite imagery to map Africa's water resources
A project funded by the European Space Agency (ESA) is helping Zambian authorities map the country's water resources using satellite imagery. Despite having one of the largest fresh water resources in Africa, Zambia, like many of its neighbours, suffers from frequent water shortages and droughts. These can be explained in part by reduced rainfall levels over the last 30 years, but also by human activity, which has impacted on the availability of groundwater. Funded by ESA, the Integrated Water Resource management for Zambia (IWAREMA) project is gathering information on existing water resources. Using data from ESA's multispectral MERIS sensor aboard the Envisat satellite, it has created maps depicting the whereabouts of groundwater, suitable dam locations, land cover and the risk of soil erosion. The aim of the project is to provide the Zambian public authorities with an information tool with which to better manage and protect this vital resource. Much of the data collected is on the Kafue River Basin, a sub-catchment of the Zambezi River Basin, which is home to more than half of the country's population, and the location of the country's capital. '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,' says Jack Nkhoma of Zambia's Department of Water Affairs. The land cover change maps will enable government authorities to identify trends with regard to deforestation, reclaimed land and new settlement areas, and to determine their long-term impact on water resources. By providing a clearer picture of the situation, it is hoped that the maps will also help authorities implement corrective measures. The data is also expected to help Zambian authorities deal with an unprecedented growth in urban populations. It is estimated that some 34% of the country's 11 million inhabitants is living in urban areas. The speed of urbanisation has meant that the public authorities are behind in developing crucial infrastructures, such as water supply and sanitation. 'With a lot of pressure from population growth and urbanisation, the land cover maps will show how demographic variables and pressures will impact natural resources,' said Mr Nkhoma. If successful, the IWAREMA project could be extended to other basins of the Zambezi. Comparisons between areas on which there is currently very little information will then be possible. IWAREMA was one of the projects initiated under ESA's TIGER scheme. Launched in 2002, the scheme aims to assist African countries to overcome water-related problems and to bridge Africa's water information gap using satellite data. To date, more than 100 African water basin authorities, universities and other organisations have become involved in TIGER projects across the continent.
Countries
Zambia