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FUTURE IMPERFECT
Increasing the water-holding capacity of the soil and
harvesting rain can be used as an anti-flood measure
as well as to reduce droughts. Typically water harvest-
ing combines more technical interventions such as
the building of depressions or small dams with bio-
logical elements like the use of vegetation-borders,
grassy belts, belts of shrubbery and trees and protec-
tion and/or restoration of infiltration areas.
The average cost to prepare and implement compre-
hensive flood prevention and anti-erosion measures
based on water conservation or harvesting depends
on the character and morphology of the land. Inex-
pensive measures could be implemented and main-
tained by landowners and would create employment.
The average costs for implementation comprehen-
sive flood prevention measures based on water con-
servation or harvesting and anti-erosion measures
for a square kilometre of land represents 0.1% of the
annual GDP of a country multiplied by the number of
years needed for implementation and then divided by
the area of the region (in km
2
).
On the benefit side, rainwater is harvested in water-
sheds in such a way that ecosystems can “produce”
enough good quality water for humanity, food and
nature, can purify polluted water, and can reduce
the risk of natural disasters like floods, droughts
and fires.
Adaptation Action:
Rainwater Harvesting
Examples of rainwater harvesting
(source: Kravcík et al. (2007)