The many faces of the Niger River

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2 The many faces of the Niger River The Niger is the third-longest river in Africa after the Nile and the Congo; it runs for 4,200 km in West Africa. It presents many different faces along its length. Subject to a tropical condition in its upper basin, the Niger River becomes the Inner Delta in Mali, where it loses about half of its water by evaporation and infiltration into the soil. In this delta where a million people live, the human activities follow the rhythm of floods: fishing at high waters and grazing and arable farming with low water. Along the Niger s course, Canoes designed for carrying passengers from one side of the river to the other near Mopti. it crosses the Sahel and winds through the Sahara before heading south where it pours their water through the many branches of a huge delta in the Gulf of Guinea in Nigeria. Each of the river s landscapes behaves differently based on the climate, precipitation patterns, the shape of drainage basins, infrastructures on the river and human activities. DID YOU KNOW? Manatee Trichechus senegalensis. The Inner Niger Delta is a vast, biodiverse flood zone, where hippos, manatees and more can be found. The Inner Niger Delta around Lake Débo. IDENTITY CARD Source: the Tingi hills Mouth: Gulf of Guinea - Atlantic Ocean Length: 4,184 km Average discharge at mouth: 5,600 m 3 /s Surface of drainage basin: 1.2 million km² Countries: Sierra Leone, Guinea, Côte d Ivoire (Ivory Coast), Burkina Faso, Mali, Niger, Benin, Nigeria, Cameroon, Chad. Oil exploitation in the Niger River Delta poses serious environmental problems with almost permanent oil slicks. Little egret catching a fish. The Inner Niger Delta is West Africa s largest wintering area for birds. Researchers have recorded 250 species there. Bamba Market in the Gao region of Mali. Watercourses are very important for the economy, allowing the goods to be transported from the production site to the trading area. The basin s population is likely to double in twenty years 12

3 The vagaries of floods The River Niger s water resources and its main tributaries along the right bank such as Bani, depends mainly on the upper basin in Guinea, Mali and Côte d Ivoire. Precipitation is more abundant in this region than in areas of the Sahel and the Sahara. However, it is uneven causing a great variability in the flow. Since 1970, the reduction of rainfall caused a sustained decline in groundwater resources and a reduction of the flooded areas in the delta. The impact of climate change in the Niger basin may also increase and decrease rainfall and discharge, varying locally based on geology and soils. The abundant flow favours fishing, navigation and irrigation throughout the course of the river, and in particular in the Inner Niger Delta. However, devastating floods regularly take place, such as in 1967 in Bamako, 1994 in the Inner Delta, 2001 on the banks of the Sankarani, and in 2010 and 2012 in Niamey. These are essentially caused by heavy runoff from bare soil resulting from drought and an increase of cultivated land, or by flooding of urban zones on the riverbed. The aim of the AMMA-Catch observatory is to have a better understanding of the phenomenon of West Africa monsoon and its impact on the environment. Researchers are carrying out a long-term monitoring of vegetation and the water cycle as well as interaction with climate. They use models of the hydrology and the ground-atmosphere exchange in order to evaluate their role and to anticipate rainfall and vegetation dynamics. In today s current context of climate change and land use, these data are vital to plan for the future economic development of the region. Climate change and human activities, land use, irrigation and dams lead to modification of the Niger River s patterns, in turn causing reduced water reserves during dry season and an increased risk of flooding and soil erosion. Upstream, in the Guinean side of the river, precipitation is extremely heavy, approximately 2,000 mm/year. In the Sahelian and Saharan parts of the river, rainfall is rarer and more irregular, with less than 600 mm/year. 340,000 people were affected, and 44 killed, following heavy flooding in August 2012 in Niamey in Niger. The 2001 floods on the banks of the Sankarani almost completely destroyed the banana plantations. Waterside houses in Bamako. The extension of habitat into high-risk areas and the combination of climate change and human activities explains the adverse effects of some floods, particularly in the Sahel. In August 2012, the Niger River reached its highest level since

4 The fertile Niger Irrigated crops, particularly rice agriculture were developed around reservoirs and traditionally in flood plains and around the river. The motor-powered pumps, commonly use during the dry season, allows small family plots to be irrigated to grow rice and vegetables. Building large hydroelectric dams and the increase in water withdrawal will affect the river s flows and will require better water management. The river s behaviour has a particular influence on the scope The life of Peul herds people in the Inner Delta are built around the cycle of transhumance. They follow the floods and high waters in the rainy season, then the gradual drying-up of the plains and secondary branches. of the flooding in the Inner Delta and therefore in the agricultural yields. Most fishing in the basin is carried out by craftsmen. Professional fishermen, such as the Bozo, are located along the river and on the Inner Delta. Farming communities also occasionally practise fishing. The fish stocks in the delta vary each year depending on flood levels. Extreme droughts, but also more intense fishing and heavy catching of young fish, have increased the pressure on this resource. Over several decades, the IRD has been working in the Niger River Basin in order to improve understanding of pluviometry and hydrological patterns subject to climatic and humans influences. These data allow better understanding and optimisation of agricultural practices. The IRD has taken part in CGIAR projects (Challenge Program on Water and Food, BFP Niger), HydroDIN, and Niger-Loire: governance and culture (UNESCO) at the French national research agency ANR RESSAC, and the ILEE federal research institute. Motor-powered pumps in the Kouakourou region. This practice allows more diverse crops (mainly bananas, but also mangos, grapefruit, etc.). The Niger River is an essential source of agricultural water in the most arid areas. The basin has a population of 50 million, and in rural areas, the majority of people are arable and livestock farmers. From the Guinean forest to the swamps at its mouth, passing through the great extensions of dry lands of the Sahel and the deserts of the Sahara, Niger River basin is home to more than 100 million people who make a living from rain-fed and irrigated agriculture, livestock farming, and fishing. The Inner Niger Delta is a vast, biodiverse flood zone, home to 120 species of fish. Collective fishing in the Bolé pond, in the Niandan River. Bozo fisherman hut, a provisional camp in the Inner Niger Delta. Harvesting sorghum in Koré Maïroua in Niger. Most agriculture in the Niger basin is rain-fed, where dry cereal crops are followed by root crops based on rainfall. Irrigation represents only 5% of agricultural surface area in the basin 14

5 Living and developing alongside the river Aware of the socio-economic challenges and concerned about tensions that can arise between the various users, the nine states along the river were associated creating the River Niger Commission in 1964, and then in 1980 the Niger Basin Authority. This intergovernmental organization ensures cooperation among its members to achieve fair and sustainable management of the 1.2 million km² of the basin. Large hydro-agricultural and hydroelectric developments on the Niger and its tributaries remain few and unequally distributed. However, several major projects are currently underway: the Niger Basin Authority is making significant investments in order to irrigate 15,000 km² by 2025, including the Fomi Dam in Guinea and the Taoussa Dam in Mali. Alongside these larger projects, smaller hydraulic facilities have proliferated along the riverbanks since the drought of 1980s. These small dams and pumps are continuing to increase in number, and are likely to have a non-negligible impact on the hydrological balance of the basin and should therefore be taken into account in terms of water management. The main objective of Gire 2 project is to provide the Niger Basin Authority the means to ensure an effectively monitoring of water resources and large hydraulic facilities to perform a peaceful, integrated and coordinated management, including: functional hydrological equipment, capacity building of officers, operational databases and improve systems for processing and dissemination of information and data. The nine countries which share the Niger basin depend mostly on the river and its tributaries for agriculture and drinking water supplies, but also for energy, transport, industry, tourism, and other purposes. Since the population is expected to double within 20 years from now and hydraulic facilities are unevenly spread over the territories, there are concerns that tensions will rise between users and countries. An ethnic Fula Rimaybe farmer is waiting for the first rains. In the Inner Niger Delta, flooding is essential to develop agro-pastoral activities. Irrigated areas near the Sankarani, a tributary of the Niger. The dam, as well as producing electricity, creates a store of water used to irrigate a vast field area. Since 1982, the operation of Sélingué Dam has altered the Sankarani River (a tributary) and up to the Inner Niger Delta. Although the discharge in times of flooding is only slightly reduced, the impact on the dry season is much more important since water is released in the dry season to ensure a water flow that enables navigation and fishing. Around 500 small hydraulic facilities have been built on the Bani River drainage basin in Mali. It is highly likely that they will affect flow behaviour, but this is impossible to quantify due to the lack of information on the size of the reservoirs, how they are operated, and the water usage. The Markala Dam is one of the largest on the Niger River 15