Africa: Water surplus will persist in Nigeria & Chad

24 October 2022

THE BIG PICTURE
The 12-month forecast through June 2023 indicates water deficits in many regions across North Africa with areas of intense deficit including exceptional anomalies in Algeria and from southeastern Libya into Egypt.

In West Africa, exceptional deficits are forecast for northern Mauritania and northern Mali, and deficits reaching exceptional intensity in southern Mali and Sierra Leone. Moderate deficits are forecast in Côte d'Ivoire between the Sassandra and Bandama Rivers and in southwestern Ghana. Deficits of varying intensity are expected in southeastern Nigeria.

Surpluses will be widespread in a belt across the southern edge of the Sahel from Burkina Faso through southern Sudan, dipping further south into Ghana, Benin, and well into many parts of Cameroon and Central African Republic (CAR). Anomalies will be intense in northern Nigeria, central Chad, and from southeastern Cameroon into CAR. In the Horn of Africa, a few pockets of deficit are forecast in central Eritrea, around Berber in Somaliland, and in south-central and western Ethiopia, including severe deficits surrounding Addis Ababa. Deficits are also forecast in pockets of southern Kenya, including Nairobi, crossing into Tanzania.

In the heart of the continent, moderate to severe deficits are forecast from western South Sudan through the eastern tip of CAR and the Ruki Sub-basin of the Congo in Democratic Republic of the Congo (DRC). In South Sudan east of Juba, surpluses will be intense and will reach into Uganda. In the mid-Atlantic, deficits are predicted in Gabon’s extreme northern and southern extents and in southern Republic of the Congo where anomalies will be exceptional. Angola can expect a few moderate pockets of deficit in the far northwest and southwest.

In southern Africa, moderate surpluses are likely at the intersection of Angola, Namibia, and Botswana. Surpluses are also predicted for south-central Botswana and in South Africa in the Kalahari and Upper Karoo regions of Northern Cape, Eastern Cape’s northern half, and North West Province. Intense deficits are forecast in small pockets north of Cape Town and on Madagascar’s central east coast.

FORECAST BREAKDOWN
The 3-month maps (below) show the evolving conditions in greater detail.

The forecast through December indicates deficits from Mauritania through northern Mali and Algeria, moderate overall but exceptional in northwestern Mauritania, the El Djouf desert region of Mali, and the Erg Iguidi desert in Algeria. In Libya, some moderate deficits are forecast in the west, intense pockets in the southeast, and surpluses will re-emerge in pockets on the coast including Benghazi. Surpluses are also expected in Egypt in pockets near the Nile. Surpluses will be widespread in a belt across the southern edge of the Sahel from Burkina Faso through southern Sudan, dipping further south into Ghana, Benin, Nigeria, eastern Cameroon, and CAR. Anomalies will be intense in several regions, particularly Chad and northern Nigeria.

In West Africa, pockets of deficit are forecast in Sierra Leone, southern Mali, southwestern Ghana, and southeastern Nigeria. In the Horn, deficits will be intense from central Eritrea through Djibouti, moderating in Somaliland and northern Somalia, and severe near Addis Ababa, Ethiopia. Surpluses are forecast in Uganda leading into nearby areas of South Sudan and Kenya, and in Rwanda reaching into DRC and Tanzania. Scattered surpluses are expected elsewhere in Tanzania as well. Deficits are expected in the Middle Congo Basin of DRC, severe deficits in CAR’s southeastern corner, and deficits of varying intensity in southern Republic of the Congo. In southern Africa, surpluses are predicted for southern Mozambique, south-central Botswana, southern Lesotho, and several regions in South Africa including Eastern Cape, Free State, and the Kalahari and Upper Karoo regions of Northern Cape. Intense deficits are forecast in small pockets north of Cape Town and on Madagascar’s central east coast.

From January through March 2023, deficits will shrink considerably, persisting in pockets of northern and southeastern Mali and southeastern Libya, and intensifying in central Sudan. Deficits near Addis Ababa will also intensify, and a few pockets will emerge in eastern Ethiopia and central Somalia. Surpluses will remain widespread in Chad and will persist in southern Sudan, eastern Cameroon into CAR, Ghana, pockets in Nigeria’s southwest and northeast, and pockets in coastal Libya and in Egypt. Surpluses will continue in northern Uganda and deficits in southern Republic of the Congo. In southern Africa, surpluses will linger in Eastern Cape and a few other pockets in South Africa and will emerge at the intersection of Angola and Namibia and into northern Botswana. Deficits on Madagascar’s central east coast will increase, reaching the city of Fianarantsoa.

In the final quarter – April through June 2023 – deficits of varying intensity will emerge across North Africa. Anomalies will be intense from Egypt into northern Sudan and southeastern Libya; from Mauritania into Mali; and in northeastern Niger. Surpluses are forecast from Burkina Faso through southern Sudan.

Please note that WSIM forecast skill declines with longer lead times.

IMPACTS
Flooding has affected 19 nations in West and Central Africa.

In Chad, officials have updated their estimates of flood impacts after what is being described as the heaviest seasonal rainfall in three decades. As of mid-October, flooding that began in July has affected over a million people, nearly quadrupling last year’s total. Over 465,000 hectares of agricultural land has been destroyed and 19,000 livestock, increasing food insecurity. At least 50,000 people were displaced in the capital, N’Djamena, when the Logone and Chari Rivers overflowed. About half of the city is underwater and the federal government has declared a state of emergency.

Over 85,000 people in Central African Republic have been affected by flooding that has continued since June, claiming 11 lives. Crops and infrastructure have been destroyed and at the end of September flood refugees were still being housed in schools, delaying the start of the school year for 10,000 children.

Residents near the Weija Dam on the Densu River in Ghana were evacuated when excessive rainfall pushed the dam above maximum operating level. Operators opened spill gates to prevent structural collapse, flooding around 1,000 nearby homes.

NOTE ON ADMINISTRATIVE BOUNDARIES
There are numerous regions around the world where country borders are contested. ISciences depicts country boundaries on these maps solely to provide some geographic context. The boundaries are nominal, not legal, descriptions of each entity. The use of these boundaries does not imply any judgement on the legal status of any territory, or any endorsement or acceptance of disputed boundaries on the part of ISciences or our data providers.

Subscribe to our monthly Water Watch List

Search blog categories

Search blog tags