Enhancing Flood Resilience in South Sudan

Water security
South Sudan

South Sudan has faced prolonged and severe flooding for over many years, with hundreds of thousands of people displaced, infrastructure and key services damaged, and livelihoods which are dependent on agriculture, pastoralism, and natural resources disrupted. The humanitarian crisis is compounded by the impact of decades of conflict, associated socio-economic challenges and the physical isolation of many of the communities. To strengthen the communities’ resilience to climate-related disasters, a feasibility assessment was conducted, identifying robust, evidence-based, and community-informed investments.

Key Takeaways

  • The feasibility assessment has successfully delivered a comprehensive analysis of flood and drought risks, and identified robust, evidence-based, and community-informed investments to strengthen resilience to climate-related disasters.
  • Complementary and mutually supportive interventions across a range of scales were proposed including major infrastructure investment, ‘small-scale’ investments that may be applied at household level, and investments which support implementation.
  • The resulting evaluated longlist of interventions provides IOM and the Government of South Sudan with a strong foundation for prioritizing and advancing targeted investments to build climate resilience at the community level.
  • A key measure of the success of the project over the long term will be if communities are empowered to develop livelihoods, become more self-sufficient and resilient to climate induced shocks.

Project Details

Started: 2024 – Completed: 2025
Ref: 231495 | Status: Completed
Project title: Flood Resilience Feasibility Assessment for the South Sudan Enhancing Community Resilience and Local Governance Project Phase II (ECRP-II)

Background

Fourteen years after gaining independence, South Sudan continues to face profound humanitarian, economic, environmental, and political challenges. Conflicts in 2013 and 2016 deepened instability, leading to widespread displacement, weakened institutions, and a fragile economy dependent on subsistence farming and cattle-based pastoralism.
Rural communities in northeastern South Sudan are particularly vulnerable due to their reliance on climate-sensitive livelihoods and limited access to infrastructure and services. Extreme weather events – especially floods and droughts – are becoming more frequent and severe, damaging farmland, disrupting mobility, and exacerbating food insecurity. For example, the 2019–2020 floods damaged over 45% of cereal-growing areas in nine counties. The World Food Programme warned in December 2023 that millions in South Sudan faced acute hunger, with levels doubling over the previous year.

Community-built dike to prevent against flooding in Kodok Town
Flooded farmland in Kodok Town

Activities

The project aims to strengthen communities by improving access to essential services, building resilience to flooding, and enhancing institutional capacity for local service delivery.
The focus is on conducting baseline studies, hydrological modelling, and stakeholder engagement to understand the local context and identify potential flood and drought resilience interventions.

Activities included desk studies, site visits, and stakeholder consultations, which informed the development of a long list of appropriate solutions.

While Arup concentrated on the feasibility assessment of large-scale infrastructure such as dykes and elevated roads, Acacia Water focused on ‘smaller-scale’ community-based solutions.

Key outputs to which we contributed are:

  • An inventory of successful disaster risk reduction interventions from South Sudan and similar environmental settings
  • Field validation and initial community consultations on the proposed long-list options
  • A comprehensive list of short-, medium-, and long-term flood and drought mitigation measures, including preliminary designs, cost estimates, and a ranking system based on environmental and social criteria

Findings

A key measure of the success of the project over the long term will be if communities are empowered to develop livelihoods, become more self-sufficient and resilient to climate induced shocks. Therefore, a range of complementary and mutually supportive interventions across a range of scales were proposed including:

  • Major infrastructure investment which includes flood defences (new dykes and strengthening existing dykes), access road improvements, measures to manage surface water flood risk, access to safe water supply, improved and flood resilient sanitation.
  • ‘Small-scale’ investments that may be applied at household level to improve soil and water conservation as well as measures to improve livelihood diversification and agricultural practices.
  • Investments which support implementation which include setting up reliable base surveys and control stations, weather and water level gauges to inform and improve predictive flood modelling into the future, and investments to assist with institutional strengthening and capacity building. A need has been identified for collaborative spatial development and governance planning to provide a tool which enables local authorities and communities to move away from reactive emergency interventions to planning for long term resilience.

The feasibility assessment has successfully delivered a comprehensive analysis of flood and drought risks across the five target counties, and identified robust, evidence-based, and community-informed investments to strengthen resilience to climate-related disasters. The resulting evaluated longlist of interventions provides IOM and the Government of South Sudan with a strong foundation for prioritizing and advancing targeted investments to build climate resilience at the community level.

Project Areas

Five target counties in the northeast were identified for physical investment in consultation with the government: Duk (Jonglei), Twic East (Jonglei), Pibor (Pibor), Fashoda (Upper Nile), and Rubkona (Unity).

Geographically, the northeast of South Sudan includes diverse ecosystems – low-lying marshes like the Sudd, savannahs, bushlands, and seasonal wetlands. The wet season (May–October) is increasingly unpredictable, often forcing people to higher ground and making road access unreliable. This movement intensifies pressure on scarce resources.

The region is ethnically diverse (including Nuer, Dinka, Shilluk, Azande, and Bari populations), with a mix of rural settlements, administrative towns like Malakal and Rubkona, and large IDP camps such as the Bentiu PoC site, home to over 112,000 people. Resource-based conflicts between pastoralists and farmers – particularly over grazing lands and water – are exacerbated by population growth and climate change.

Geographic scope: Local

Downloads and Links

There are no documents and links available for this project.

In Cooperation With

Commissioned by:

International Organization for Migration (IOM)

Funded by:

The World Bank

Project partners:

Acacia Water Groundwater Relief (GWR) Arup University of the West of England (UWE) University of Reading Cardiff University Groundwater Science

Contact

Lenna Merton

Hydrologist

+31 6 24 36 40 77
lenna.merton@acaciawater.com
lennamerton

Related topics:

Climate resilience, Drought, Flood resilience, Nature-based solutions (NbS), Small-scale interventions

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