Forest and Water Programme

Managing the Forest-Water Nexus and Mitigating Flood Events


Water-related disasters accounted for 74 percent of all-natural disasters between 2001 and 2018, and their frequency and intensity are generally rising. Changes in land cover/use, population growth, and climate change have resulted in an increase of floods frequency from an average of 127 events per year in 1995–2004 to 171 events per year in 2005–2014. Consequently, communities, agriculture, livelihoods, and the economy have been severely impacted.  During the past 20 years, floods and droughts affected over three billion people, causing 166,000 deaths and economic damage of almost US$700 billion, with Africa and Asia being the most affected continents. Sudan, for example, has recently faced an increase in hunger levels due to flooding levels rising, which submerged entire villages, homes, livestock, and crops.  


The case of Kenya's Great Rift Valley

There are two important water resources in Kenya`s Great Rift Valley: the Lake Baringo, which provides fresh and drinkable water to many people in the region; and the Lake Bogoria, home to an important colony of flamingoes. Unfortunately, deforestation combined with months of unusually heavy rains has resulted in rising to alarming levels of both water resources, generating floods in the region. Consequently, thousands of acres of farmland were lost; communities had to migrate to safer regions; vital tourism and agriculture sectors were severely impacted; and homes, hospitals, and schools are underwater. There is also a concern regarding a huge ecological disaster due to the possibility of Lake Baringo and Lake Bogoria contaminate each other, as Lake Bogoria is salty.

In order to mitigate the flood effects, a non-profitable organization, the Rehabilitation of Arid Environments (RAE), is supporting the rehabilitation of degraded drylands, aiming to enhance the landscape resilience and establish sustainable income from these areas. Capacity building and technical support have also been provided to communities. As a result of these activities, the local people involved in the community-based solutions developed by RAE are reaping multiple socio-economic benefits from their once degraded lands.


Flood damage can be mitigated by managing forests sustainably. Trees and forests are able to improve landscape resilience and may reduce the frequency with which a given flood peak occurs, by rapidly increasing evapotranspiration and enhancing soil infiltration. Forest ecosystems store water during heavy rainfall, then release it slowly into streams, which lessens the severity of floods and maintains stream flows during dry periods. Tree roots and litter increase the permeability of the soil and facilitate infiltration processes, reducing the run-off of rainwater, and reducing flood risks. Therefore, in order to cope with climate change and natural disasters, it is essential to manage forest ecosystems, targeting landscape resilience and mitigation of water-related disasters.