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M. O. Eduvie and I. F. Oseke
1 Introduction
A dam is a man-made structure built across sections of a river or stream to retain water,
which is generally used for agricultural purposes such as farmland and garden irrigation and the watering of livestock (Lodha 2007). It also can serve as a constructed
barrier across a stream or river to impound water and raise its level for various
purposes, such as drinking water supply and irrigation systems, and also increase
river depth for navigation, generating electricity, control of water flow during times
of floods and droughts, and the creation of artificial lakes for fisheries and recreational
use. Many dams serve multiple of these purposes (Uyigue 2006). However, in the past
twenty (20) years especially in 2017/2018, there has been upsurge in extreme events
which negatively impacted the dams as a result of changes in climate (NASRDA
2012). In this particular event of 2017/2018, the rainfall period was not as long as
anticipated. On the average, rainfall period always occurs between March/April to
September/October but in the 2017/2018, the rains only occurred between April
to early August. Climate and water resource systems have a special relationship
insofar as water resources depend on the hydrological cycle which itself is part of
the climate system (Stainforth et al. 2005). The impact of climate change on the function and operation of existing water resource systems and infrastructures, including
hydropower, structural flood defenses, drainage and irrigation systems, as well as
water management practices (Alvarez et al. 2014) are critical. As effects of climate
change on water resource systems accumulate, there is corresponding impact of other
stresses, such as population growth, changing economic activity, land-use change and
urbanization (Thornton et al. 2008).
The concept of climate change revolves around the atmospheric concentrations
of greenhouse gases (GHG) which have increased since the pre-industrial era due to
human activities, primarily the combustion of fossil fuels and changes in land use
and land cover (Gwary 2008). These, together with natural forces, have contributed
to changes in the Earth’s climate over the twentieth century. Land and ocean surface
temperatures have warmed, the spatial and temporal patterns of precipitation have
changed, sea level has risen and the frequency and intensity of cumulative pressure
from climate change events have increased. These changes have affected dams and
reservoirs and other water infrastructures (Gwary 2008).
The importance of water resources to man cannot be overemphasized. These
include provision of water for domestic use, agricultural production, fishing, transportation, industrial use, hydro-electric power, recreation, tourism and mining.
Furthermore, according to the World Bank (2014), every development challenge
of the twenty-first century, such as food security, management of rapid urbanization, energy, security, environmental protection and adaptation to climate change
requires urgent attention to the infrastructure management of water resources. Available information and statistics indicate that in recent times, climate variation or
change is becoming more extreme in certain areas. This dynamic is not specific to
Nigeria of course, but rather is represented by a rapidly growing global catalogue
M. O. Eduvie and I. F. Oseke
1 Introduction
A dam is a man-made structure built across sections of a river or stream to retain water,
which is generally used for agricultural purposes such as farmland and garden irrigation and the watering of livestock (Lodha 2007). It also can serve as a constructed
barrier across a stream or river to impound water and raise its level for various
purposes, such as drinking water supply and irrigation systems, and also increase
river depth for navigation, generating electricity, control of water flow during times
of floods and droughts, and the creation of artificial lakes for fisheries and recreational
use. Many dams serve multiple of these purposes (Uyigue 2006). However, in the past
twenty (20) years especially in 2017/2018, there has been upsurge in extreme events
which negatively impacted the dams as a result of changes in climate (NASRDA
2012). In this particular event of 2017/2018, the rainfall period was not as long as
anticipated. On the average, rainfall period always occurs between March/April to
September/October but in the 2017/2018, the rains only occurred between April
to early August. Climate and water resource systems have a special relationship
insofar as water resources depend on the hydrological cycle which itself is part of
the climate system (Stainforth et al. 2005). The impact of climate change on the function and operation of existing water resource systems and infrastructures, including
hydropower, structural flood defenses, drainage and irrigation systems, as well as
water management practices (Alvarez et al. 2014) are critical. As effects of climate
change on water resource systems accumulate, there is corresponding impact of other
stresses, such as population growth, changing economic activity, land-use change and
urbanization (Thornton et al. 2008).
The concept of climate change revolves around the atmospheric concentrations
of greenhouse gases (GHG) which have increased since the pre-industrial era due to
human activities, primarily the combustion of fossil fuels and changes in land use
and land cover (Gwary 2008). These, together with natural forces, have contributed
to changes in the Earth’s climate over the twentieth century. Land and ocean surface
temperatures have warmed, the spatial and temporal patterns of precipitation have
changed, sea level has risen and the frequency and intensity of cumulative pressure
from climate change events have increased. These changes have affected dams and
reservoirs and other water infrastructures (Gwary 2008).
The importance of water resources to man cannot be overemphasized. These
include provision of water for domestic use, agricultural production, fishing, transportation, industrial use, hydro-electric power, recreation, tourism and mining.
Furthermore, according to the World Bank (2014), every development challenge
of the twenty-first century, such as food security, management of rapid urbanization, energy, security, environmental protection and adaptation to climate change
requires urgent attention to the infrastructure management of water resources. Available information and statistics indicate that in recent times, climate variation or
change is becoming more extreme in certain areas. This dynamic is not specific to
Nigeria of course, but rather is represented by a rapidly growing global catalogue