The region is paying a heavy price for destroying natural systems that help to mitigate the effects of flooding. Over the past few months, El Niño rains pounding the East African region have led to dire consequences including the massive loss of lives and property.

Experts say massive runoff is unable to flow into rivers, lakes and the ocean due to man-made obstructions in its natural course. Vegetation cover, for example, has been depleted to pave the way for human settlement.

“We have destroyed our natural vegetation, especially forests and wetlands, which has exacerbated the rise in flooding because rain water no longer filters into the ground,” said Violet Matiru, a Nairobi-based environmental consultant.

Described as “biological supermarkets” — because they produce lots of food that attract animal and bird species — wetlands not only clean river water, but also control floods, experts say.

Mordecai Ogada, a wildlife ecologist based in Nanyuki, in Kenya’s Rift Valley said a good natural vegetation cover especially on slopes helps to control flooding and prevent landslides.

“A good forest cover lowers the speed at which rain falls, making it easier for the water to seep into the ground,” said Dr Ogada. “Hilly countries like Rwanda are particularly prone to landslides.”

Just recently for example, nearly 50 people were killed after a weekend of heavy rains in Northern and Western Provinces.

The ecologist added that the lack of proper planning of cities, towns and other human settlements is partly to blame for flooding.

“Climate change causes the rain, but our lack of planning causes the landslides and flooding,” said Dr Ogada, citing Nairobi where watersheds and waterways have been destroyed to pave the way for buildings.

Salisha Chandra, an environmentalist said that the loss of vegetation leaves the ground open to soil erosion.

“This is because it lacks the support of roots to hold it together,” she said, adding that there are different causes of flooding in rural and urban areas.

“In urban areas, we have built unsustainably without regard to the environment; there are buildings on riparian lands and poor drainages made worse by the reckless disposal of waste including plastics that clogs drainage systems,” said Ms Chandra.

She added: “In rural areas, flooding is caused by human activities such as overgrazing, deforestation and sand dredging.”

According to the Food and Agricultural Organisation, East Africa has a total forest cover of 134 million hectares, but lost 1,357,000 hectares between 1990 and 2000.

FAO says that although Uganda has the highest rate of forest destruction, the largest area of deforestation occurs in the Sudan, “where it is estimated that almost one million hectares are deforested annually.”

The greatest problem is that heavy deforestation occurring in the region is not balanced by tree planting while people have settled on the steep water catchment areas where they end up cultivating unsustainable farms.

According to the United Nations Office for the Co-ordination of Humanitarian Affairs, enhanced rainfall due to El Niño was favourable to most of Kenya, Rwanda, Burundi, Uganda and Tanzania; leading to good pasture, crop development and replenishment of water sources, and an overall improvement in the food and nutrition security for the last season (October-December, 2015).

Excessive rains in late 2015 however, led to flooding that affected an estimated 600,000 out of an expected two million people in parts of Somalia, Kenya, Ethiopia and Uganda.

In Uganda, reports show that floods have displaced up to 300,000 people so far with the worst affected areas being in the north and east of the country, including in Mbale, Manafwa, Bukeda, Budadu, Kumi, Soroti, Katakwi, Amuria, Lira, Pader, Kitgum, Nebbi, and Gulu districts.