Elements for Life

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originally two metres deep, is now only 30 cm deep due to an

accumulation of sediment and rubbish. It is also linked to the

increased number of houses which yield much more runoff

from a given quantity of rain.

Local Kampala people claim that floods are now more

frequent and more severe. The flooding used to occur in

predictable cycles in the two main rain seasons of April-May

and October-November, but now occurrences have become

erratic and unpredictable

The response to floods in July 2006 was characterized by ad

hoc individual short-term efforts to survive and protect prop-

erty. In addition, some residents undertook collective work to

open up drainage channels, some temporarily moved to lodges

and public places like mosques and churches until the water

level receded and others constructed barriers to water entry at

the doorsteps. Some made outlets at the rear of their houses

so any water entering their homes flowed out quickly. There

were limited collective efforts at the community level, and

virtually no significant intervention by the relevant local

government at the division level.

What helped the residents most was the fact that the rains

that caused the flooding were not the continuous peak rains

that last several days, such as those experienced in April and

November. What limited the response of the residents was the

fact that almost all activities were uncoordinated, and were at

the individual level.

Case study: Maputo, Mozambique

In Block 40B of the Luis Cabral slum neighbourhood of

Maputo, Mozambique, residents argue that flooding has wors-

ened since 1980, pointing out that the 2000 floods completely

destroyed the area. A single one-day rain event can cause floods

that persist for three days. If the rains persist from three days

to one week, the water depth rises to one metre and it may

take a month to disappear.

urbanizing region – climate change is already threatening that

goal, putting the continent’s already strained urban cities under

additional stress.

Flooding in urban areas is not just related to heavy rainfall

and extreme climatic events, but also to changes in the built-

up areas themselves. Urbanization aggravates flooding by

restricting where floods waters can go, covering large areas of

ground with roofs, roads and pavements, obstructing sections

of natural channels, and building drains that ensure that water

moves to rivers more rapidly than it did under natural condi-

tions. As people crowd into African cities, these human impacts

on urban land surfaces and drainage intensify. Even quite

moderate storms now produce high flows in rivers because

more of the catchment area supplies direct surface runoff from

its hard surfaces and drains.

Flooding from rising sea levels as a result of climate change

is a potential hazard for the quarter of Africa’s population living

in coastal zones.

It is estimated that the average annual

number of people in Africa impacted by flooding could increase

from one million in 1990 to 70 million in 2080.

The capital

of The Gambia, Banjul, could disappear in 50-60 years through

coastal erosion and sea-level rise, putting more than 42,000

people at risk.

Trends in urban flooding in Africa

Many African cities have experienced extreme flooding since

1995. Heavy rains and cyclones in February and March 2000

in Mozambique led to the worst flooding in 50 years and

brought widespread devastation to the capital city, Maputo.

Upwards of one million people were directly affected. Water

and sanitation services were disrupted, causing outbreaks of

dysentery and cholera.

In Ethiopia in August 2006, floods killed more than 100

people in the capitalAddis Ababa, and destroyed homes in the

east of the country after heavy rains caused a river to overflow.

The overflowing Dechatu river hit Dire Dawa town at night

drowning 129 people and wiping out 220 homes.

The clear messages emerging are that:

• Urban flooding is becoming an increasingly frequent and

severe problem for the urban poor

• Climate change is altering rainfall patterns and increasing

storm frequency and intensity, thus increasing the poten-

tial for floods

• Local human factors, especially urban growth, occupation

of flood plains and lack of attention to waste management

and maintenance of drainage channels, are also aggravat-

ing the flood problem.

Case study: Kampala, Uganda

In Kampala, Uganda, construction of unregulated shelters by

poor inhabitants has reduced infiltration of rainfall, increas-

ing runoff to six times that which would occur in natural

terrain. Some of the increase is probably due to climate change,

but some is the direct result of land cover change.

Fifty-nine-year-old Masitula Nabunya, of Bwaise III Parish

in Kampala said that after the 1960 floods a channel from

Nsooba to Lubigi was dug and workers were employed to clean

it regularly. There were no further flood problems until the

1980s, but since then she has had to rebuild her house after

flooding six times. Flooding in these places is now much more

frequent, every small downpour appearing to produce intense

flooding. Some of this is because the main drainage channel,

Photo: ActionAid Sierra Leone. Freetown, Sierra Leone

Girl affected by flood