THIS ARTICLE IS re-published from Conversation under Creative Commons License.
Massive floods have once again engulfed much of South Sudan as record water levels in Lake Victoria flows downstream through the Nile. Over 700,000 people have been affected. Hundreds of thousands of people have already been forced to leave their homes by massive floods a few years ago and they did not return when this fresh threat appeared.
Now, there are fears that these displaced communities may never return to their lands. While extreme weather regularly displaces entire communities in other parts of the world, this could be the first lasting mass displacement due to climate change.
In the Sudd region of South Sudan, the Nile flows through an extensive network of smaller rivers, swamps and floodplains. It is one of the largest wetlands in the world. Flood levels vary greatly from year to year, mainly due to fluctuating water levels in Lake Victoria and controlled discharges from a dam in Uganda where the lake flows into the Nile.
The unique geography of the Sudd means that floods there are very different from those elsewhere. Most floodwaters cannot flow freely back into the main White Nile channel, and the water has difficulty infiltrating the clayey and silty floodplain soil. This means that floods last a long time, often subsiding only as the water evaporates.
People can’t cope anymore
The Sudd communities, including the Dinka, Nuer, Anyuak and Shilluk, are well adapted to the typical ebb and flow of seasonal floods. Herders move their cattle to higher ground when floodwaters rise, while clay walls made of compressed mud, they protect homes and infrastructure. During the flood season, fishing sustains local communities. When the floods subside, crops such as peanuts, okra, pumpkins, sorghum and other vegetables are planted.
However, record water levels and the long duration of recent floods have strained these native coping mechanisms. The prolonged flooding conflict in the country further confined their ability to cope. Older community members who spoke to our colleagues at the humanitarian aid charity Médecins Sans Frontières said that fear of conflict and violence had prevented them from moving to regions of sheltered ground they found during the severe flooding of the early 1960s.
Around 2.6 million people were displaced in South Sudan between 2020 and 2022 alone, as a result of both conflict and violence (1 million) and floods (1.5 million). In practice, the two phenomena are linked, as floods have displaced pastoralists come into conflict with resident farmers on the land.
Standing flood water as well leads to an boost in waterborne infections such as cholera and Hepatitis Esnakebites and vector-borne diseases such as malaria. As people become malnourished, these diseases become more risky. Malnutrition is already a large problem, especially for About 800,000 people who fled to South Sudan from Sudan following the outbreak of a separate conflict there in April 2023.