The Lower Incomati Flood Risk Management Project


The Incomati Flood Risk Management Project will reduce flood and drought vulnerability for outgrowers, smallholder farmers and 50,000 households in the Lower Incomati floodplain in Mozambique. In addition, the Incomati Basin transboundary Early Warning Flood Forecasting System – produced by CRIDF for live availability on a website – will also benefit eSwatini and South Africa. The project will also improve climate resilience along the supply chains of resident sugar companies.

Investment request

Up to £6 million grant funding for outstanding feasibility studies, detailed design and construction related to the proposed flood risk management infrastructure.

Main sponsor(s)

Private sector: Tongaat Hulett and Illovo Sugar

Public sector: ARA-Sul (government authority responsible for the operation and management of the Incomati River in Mozambique) and the National Institute for Irrigation in Mozambique (INIR)

Key facts

Water infrastructure type

Flood risk management (flood embankment with sluice gates to control the direction of flow for both flooding and low flows)

Country(ies), location


Transboundary basin

Inco-Maputo Basin

Development impact

  • Reduced flood vulnerability for outgrowers, smallholder farmers and over 50,000 households
  • Increased climate resilience with commensurate socio-economic benefits for all parties along the agricultural value chain
  • Reduced flood risks and damage for outgrowers, and smallholder farmers
  • Improved daily water resources management

Download PDF

  • Additional feasibility studies: geotechnical investigation, environmental and social studies, localised flood resilience design measures, environmental licence and permits.
  • Detailed infrastructure design phase: design of sluice gate, flood embankment, etc.
  • Procurement process, appointment of contractor and construction with handover to the operator – ARA-Sul.
  • Development of operating rules.
  • Institutional arrangements per phase of the project life cycle.
  • Institutional arrangements per project life cycle phase.
  • Enhancing livelihoods components and gender and social inclusion impacts.
  • Sugar cane and subsistence farming remains a significant contributor to poverty alleviation within the Lower Incomati floodplain.
  • The floodplain has experienced several severe floods and droughts over recent decades, with increasing frequency and intensity and devastating impacts due to climate change.
  • The project will significantly reduce flood vulnerability for over 250,000 people in the Basin. The infrastructure can also be used to optimise the daily management of water resources.
  • The project brings together the public and private sectors with innovations at watershed and value chain levels, contributing to flood risk management and ecologically sound water management.

The estimated annual costs avoided (by implementing the infrastructure) for a 1 in 10-year flood event amount to at least £21 million. The annual cost requirement for the infrastructure is £47,000 per year. The benefits that can be realised through the project far exceed the annual costs with a cost–benefit ratio of at least 4.5.

CRIDF has completed engineering and social prefeasibility studies, including a two-dimensional hydraulic model covering an area of 1,300 km2, proving the benefits of the project. The infrastructure solution includes a flood embankment with sluice gates to control the direction of flow for both flooding and low flows. The structure will have the ability to divert water from the Cuenga River to the Incomati River during flood events and reduce some of the flooding impacts further down the Basin for low return-period flood events. During normal flow conditions, releases will be made for environmental purposes, to enhance water quality and for irrigation flows down the Cuenga River. This can be potentially attained by the development of operating rules that permit flexible releases designed to achieve these purposes. For example, the diversion of water into the Cuenga can be utilised to enhance water quality during extensive dry periods.

A memorandum of understanding detailing the financial commitments and roles and responsibilities of the parties involved in the Project is currently being reviewed for signature. The private sector co-financiers are Tongaat Hulett and Illovo Sugar, and the public sector partners are ARA-Sul and INIR.

The livelihoods resilience and capacity building components of the Project address the needs of outgrower and subsistence farmers in the Basin. This includes the development of rural advisory services and outgrower strategies for different areas within the Basin, training on sustainable agriculture practices, small-scale and localised flood risk interventions and improved access to pertinent information.

In line with Mozambican legislation, the Project will produce environmental and social impacts assessments and environmental and social management plans, with stakeholder consultations.