Water Quality and Sediment Behaviour of the Future: Predictions for the 21st Century (Proceedings of Symposium HS2005 at IUGG2007, Perugia, July 2007).  IAHS Publ. 314, 2007, 293-299

 

Runoff erosion control for a sustainable water supply in Niamey, Niger Republic

 

ISSOUFOU Abdoulkader

FACOM, Save the Children UK, Tessaoua, Niger Republic

kader_issoufou@yahoo.com

 

Abstract Runoff erosion is very detrimental to soils and their use, especially in semi-arid countries, and controlling it is a day-to-day preoccupation of people and governments. The flowing water erodes farmland and destroys infra­structures. Also, overland flow transports silt and deposits it in depress­sions. Silting is one of the most important causes of flow reduction in the River Niger, which serves as the source of domestic water supply for Niamey and other riverside towns and villages. In order to protect this river and its riparian communities, the Niger Republic and the Niamey Urban Communality (CUN) governments adopted a number of measures to control runoff erosion so as to guarantee three million cubic metres of domestic water supply, the need of only a few days. These were mostly structural and/or agronomic methods. The present study examines the control measures in Niamey Township from 2000 to 2006. The methodology used included interviews with the local population, technicians and engineers handling the erosion control activities. Some field investigations were also undertaken to determine the sediments caught upstream of the constructions, and view the effectiveness of the control measures. After a critical examination of the techniques implemented, it emerges that not all were effectively constructed. The efficiency of any erosion control measure is conditioned by the total involvement of the local population. There is, therefore, a need for a large-scale campaign to enlighten the people of the importance of the control activities so as encourage them to fully participate in the control work and in maintaining the existing constructions.

 

Key words erosion control; River Niger flow; CUN (Niamey Urban Communality)