Water Resources and Their Management in an Increasing Urban Demography: The Case of Dakar City in Senegal

Abstract

The United Nations classifies Senegal as a water-poor country (less than 1000 m3 per capita of freshwater reserves) and about 20% of its population did not have access to a drinking water supply (estimates of 2015). Economic growth and the fight against poverty in Senegal depend essentially on the availability of water for the development of agricultural and industrial activities, in addition to satisfying domestic uses. As a developing country, Senegal’s human, monetary and institutional capacities are often limited to providing clean and sufficient water efficiently to its citizens. This article examines the management of water scarcity in the city of Dakar (capital of Senegal) in a context of increasing demography and urbanization. However, Senegal has sufficient water resources to meet the demand if the available resources are properly managed. As a result, several initiatives are under way in Senegal to mitigate water problems and protect the country’s water resources: reducing pollution, improving access to drinking water and setting up rational and equitable exploitation with a constant concern for sustainable development.

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
Chapter
Water Resources and Their
Management in an Increasing
Urban Demography: The Case of
Dakar City in Senegal
CheikhFaye
Abstract
The United Nations classifies Senegal as a water-poor country (less than 1000m3
per capita of freshwater reserves) and about 20% of its population did not have
access to a drinking water supply (estimates of 2015). Economic growth and the
fight against poverty in Senegal depend essentially on the availability of water for
the development of agricultural and industrial activities, in addition to satisfying
domestic uses. As a developing country, Senegal’s human, monetary and institu-
tional capacities are often limited to providing clean and sufficient water efficiently
to its citizens. This article examines the management of water scarcity in the city of
Dakar (capital of Senegal) in a context of increasing demography and urbanization.
However, Senegal has sufficient water resources to meet the demand if the avail-
able resources are properly managed. As a result, several initiatives are under way
in Senegal to mitigate water problems and protect the country’s water resources:
reducing pollution, improving access to drinking water and setting up rational and
equitable exploitation with a constant concern for sustainable development.
Keywords: water resources, management, urbanization, water scarcity, water policy
. Introduction
The Republic of Senegal, located at the extreme western tip of the African
continent, covers an area of 196,722km2 for a population of 13,508,715 inhabitants
[1]. There are three climatic domains in Senegal, from south to north: the southern
Sudan, northern Sudan and Sahelian domains, each domain having two variants
(coastal and continental) [2]. Located in the tropical zone, Senegal has a Sudano-
Sahelian climate with annual rainfall ranging from about 1250mm in the south to
just over 200mm in the north. The potential of Senegal’s water resources (surface
and groundwater) is important. Three rivers originating from Guinea (the Senegal,
Gambia and Kayanga rivers) irrigate a large part of the country [3, 4]. Alongside
these two large rivers, there are smaller rivers characterized by intermittent flows
(Casamance, Kayanga, Sine-Saloum (Figure ). Five management and planning
units (PMUs) have been established for the management of these different catego-
ries of water resources (1. Senegal River Valley, 2. Peanut Basin, 3. Senegal-East, 4.
Casamance, 5. Cape Verde Peninsula) subdivided into 28 sub-units (Figure ) [5].

Resources of Water

Groundwater is also an essential component of Senegal’s water potential and
generally consists of four major aquifer systems corresponding to the main geologi-
cal formations: the superficial aquifer system or “terminal complex” (Quaternary);
the intermediate aquifer system (Eocene and Paleocene); the deep aquifer system
(or Maestrichtian); the aquifer system of the basement [6].
In Senegal, the potential for water resources (surface and groundwater) is high
and the availability of renewable water is currently estimated at around 4747m3/
inhabitant/year [6]. Estimates indicate about 80% of its population have access to
a drinking water supply in 2915 [7]. However, the United Nations classifies Senegal
as a water-poor country with less than 1000m3 per capita [8]. Thus, the issue of
water has become a national concern given the range of issues facing the sector [9].
These problems include, among others, climate variability, vulnerability of water
resources, poor distribution of water availability in space and time, poor water
quality in some places. The water crisis can be explained both by the absolute lack
of physical availability, poverty and inadequate water management policies. In
general, Senegal has a large potential for water resources, but its uneven distribu-
tion, its overabundance in the rainy season often causes catastrophic floods and
shortage in the dry season causes severe drought conditions resulting in crop losses,
livestock, public health problems and environmental degradation [10].
These numerous factors, such as global warming (recurring and severe
droughts and floods), contamination of drinking water and lack of investment in
water resources have exacerbated the water crisis, whose role in the achievement
of its development objectives is incommensurate [11]. Its economic performance
and the reduction of poverty depend mainly on the availability of drinking water.
A set of economic activities in Senegal (agriculture, industrialization, energy
production and tourism) are inherent to the availability of water resources. At the
same time, access to safe and sufficient water is necessary for the well-being of the
population.
Senegal is home to some major cities, namely Dakar, Pikine and Touba, Thies.
The capital of Senegal, Dakar, was founded by Faidherbe in 1862, on the site of
a fishing village. It was the capital of the AOF from 1902. Enjoying a strategic
geographical location, the city is since the colonial era, a maritime and air junction
between Africa, Europe and America. It covers an area of 550km2 and has about
Figure 1.
Water resources management and planning unit in Senegal (source: DGPRE).

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Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
23% of the total population of Senegal estimated 15,256,346 inhabitants, according
to demographic projections in 2017 [12]. It is the largest city in Senegal and is its
political, administrative, economic and cultural center.
The water cuts that have become commonplace in many parts of the country,
affect more seriously the capital, Dakar where the daily deficit is estimated at more
than 20,000m3. With a consumption of 360,000m3/day, the capital struggles to
quench its thirst and satisfy its water needs. The Senegalese Water (SDE) needs
300,000m3 per day to meet the demand of the Dakar population, but it drags a
heavy deficit in the correct supply of water. At present, a large part of the city’s
population does not have access to running water 24hours a day. From 200,000
subscribers in 1996, the SDE is now struggling to satisfy its 800,000 current
subscribers.
In Senegal, the urban population is estimated at 6,541,504 people in 2015 includ-
ing 3,360,728 for the Dakar region [12]. In these urban areas, the rate of access by
connection within the covered perimeter stabilizes in December 2015 at 88.9% with
96.2% for the Dakar region. Thus the total production of water was 172.27mil-
lionm3 against an annual forecast of 169.7millionm3, or 110% of realization.
For the Dakar water supply system (WSS), production reached 124.2millionm3
[13]. As a result, there is a tendency to saturate the facilities of the Dakar AEP (for
example, Mékhé is running at almost 24hours). Because of the size of the popula-
tion of Dakar, part of this population does not have access to either an improved
water source or running water. For example, some outlying districts (in the suburbs
of Dakar) do not receive water every day, while others almost never receive water
because of the low water pressure.
In some cities in Senegal, the biggest challenge in the city is often lack of water
supply. For example, residents obtain water from individual connections, public
connections, wells, springs and water vendors that are not monitored [11]. In
addition, water pollution does not save tap water and its consumption can often
be harmful to the health of populations. It is for this reason that a good part of the
population prefer bottled water for their consumption.
The city of Dakar has been chosen for the management of water scarcity in a
context of growing demography and urbanization. Due to increased water demand
in the Senegalese capital, residents of some neighborhoods are frequently randomly
supplied with running water, with the suburbs being the most affected. The ever
increasing hydraulic equipment fails to meet the needs of the population. The diffi-
culty of supplying drinking water, which often strikes the Dakar inhabitants, comes
in the context of global warming and the removal of resources that are increasingly
important. Suddenly, the Senegalese government must expand its production
capacity and distribution networks if it wants to keep pace with unprecedented
population growth.
. The challenges facing the water sector in Senegal’s main cities
As a developing country, Senegal’s human, monetary and institutional capacities
are often limited to providing clean and sufficient water efficiently to its citizens.
Water scarcity in large cities like Dakar is chronic and continues to worsen with
increasing urbanization and pollution of the resource. Most of the time, SDE water
disruption notices are the norm in urban areas (Figure ). Water scarcity may
worsen in the future for several reasons: (1) increased water demand due to rapid
urbanization, (2) poor water management, (3) degradation continuous water
sources, (4) irregular weather conditions, (5) old and dilapidated water infrastruc-
ture, and (6) the incompetence of the water distribution companies.

Resources of Water

. Growing populations and urbanization
Senegal, like many other developing countries in Africa, is experiencing rapid
urbanization. In 1960, its population was estimated at 3.207million people and in
2017, 15.851million people (Figure ) [14]. The urban population has grown from
738,000in 1960 to 7409million in 2017 (Figure ). This urban population, which
accounted for only 23% of the total population of the country in 1960, therefore
rose to 45.9% in 2015. The share of the urban population increased considerably
between 1960 and 2014. The data show that 23% of the population living in urban
areas in 1960 increased to 45.9% in 2015. The share of the population living in
urban areas has increased dramatically in Senegal in recent decades. Thus, the
urban growth rate is 4.78 and 3.46%, respectively over the periods 1960–1985 and
Figure 2.
Notice of disturbance of water supply by Senegalese water.
Figure 3.
Senegal’s total population: semi-annual estimates of the resident population from 1960 to 2017 (source: World
Bank database).

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Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
1985–2015. This rapid pace of urban growth can be explained by the drought of the
1970s [2] and its corollary rural exodus.
According to United Nations estimates, the urban population of Senegal will
increase to 11.778million by 2030, which will represent 53.24% of the national
population (22.123million in 2030). As for the city of Dakar, its population will
increase to 4.339million by 2030 (Figure ), which will represent more than
38.84% of the urban population [14]. Urbanization does not only mean swelling of
the population, but also an increase in the area requiring better services. The rural
exodus from sub-Saharan Africa is the main cause of the rapid growth of the urban
population. To cope with the strong urban growth, water production has risen
drastically, from 95.32millionm3 in 1997 to 172.27millionm3 in 2015 (Figure ).
The growing population (Figures  and ) continues to put pressure on available
water resources, resulting in a reduction in per capita water availability. According
to projections, 70% of the world’s population will live in urban areas by 2050 [15].
The growing population continues to increase the demand for water for domestic,
industrial and agricultural purposes.
Africa currently has three main causes: (1) displacement of people from
rural areas to urban centers; (2) the increase in the urban population, especially
when economic opportunities extend to previously rural areas; and (3) the
development of previously rural areas in urban areas due to increased economic
activity [11]. Although it is difficult to define exactly an urban environment, it is
widely accepted that the term could be determined by location, size of popula-
tion and percentage of non-agricultural activities, pressures on environmental
resources such as water. In recent years, urbanization of rural areas has increased
considerably.
Although urbanization has many economic and social benefits, it causes many
environmental problems such as loss of biodiversity, air and water pollution and
increased pressure on arable land [16]. It has directly affected the availability and
quality of water due to increased demand and pollution resulting from its many
applications. Many developing countries are facing the problem of access to safe
drinking water. In Senegal, rapid urbanization has prevented some cities from
coping with the huge demand for clean and sufficient water. In Dakar, faced with
strong urban growth (an average of 120,000 people per year), the improvement
and expansion of infrastructure is very expensive and, as a result, does not generally
keep pace with the growth. This makes wastewater management very problematic.
Figure 4.
Urban population of Senegal: semi-annual estimates of the resident population from 1960 to 2017 (source:
World Bank database).

Resources of Water

In addition, pollution from agricultural production (urban farmers irrigating their
crops with untreated wastewater) and industrial production has become one of the
biggest challenges for Senegal’s water resources [17]. In addition, because of the
growing population and its corollary the increase in water needs, the lack of protec-
tion of water sources, the scarcity of the resource and the pollution it faces are a
source of hindrance improved and protected water.
Figure 5.
Urban population of three cities in Senegal: semi-annual estimates of the resident population from 1960 to 2035
(source: World Bank database).
Figure 6.
Evolution of water production by the SDE (SONES perimeter) from 1997 to 2015.

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Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
. Contamination of available water
The water sources available in Senegal are frequently affected by pollution of
chemical, microbiological or thermal origin. Chemical contamination of this water,
often used for drinking, can result from the presence of excess nutrients, acidi-
fication, salinity, heavy metals and organic pollutants [18]. Reports indicate that
industries at 32.5% and agriculture at 14% are the sectors that contribute most to
the economic development of any population [19]. On the other hand, 80% of the
water contamination comes from these two important sectors. Agricultural prac-
tices, industrialization, mining, and open sewer lines parallel to the water system
are responsible for most of the problems affecting water quality (Figure ).
The lack of adequate management of liquid and solid waste results in the deposit
of this waste directly into water bodies (Figure ), which contributes to the vicious
circle of water destruction. In fact, the growth and development of agriculture in
Senegal has led to an increase in the use of fertilizers. Agrochemicals end up in bod-
ies of water causing considerable pollution. In addition, most industrial water treat-
ment plants discharge partially treated or totally untreated effluents into surface
water sources, which often contain high levels of toxic substances. These pollutants
and other pollutants of domestic origin continue to cause environmental problems
[11]. Many Senegalese living in informal urban areas lack access to safe drinking
water, often resulting in multiple epidemics that affect their health and livelihoods.
In addition, large leaks in water pipes (Figure ), dilapidated infrastructure and
illegal connections still hinder the availability of drinking water supply. Due to
the large leaks in the water channels, the treated water is sometimes contaminated
before reaching the users.
Figure 7.
Water quality degradation factors in Senegal: (1) CSS effluent discharges into Lake Guiers; (2) water line
between the lake and Dakar damaged; (3) domestic uses on Falémé; (4) equipment for washing gold on the
banks of the Falémé.

Resources of Water

. Degradation of water sources
The main sources of water in Senegal, beyond the groundwater, are surface
water (rivers and lakes that are very attractive for agriculture and populations). The
watersheds that cross the national territory have experienced two major pressures
in recent years on their water resources: (a) pressures from natural sources (climate
variability and change); (b) anthropogenic pressures (dams, rapid population
growth and various productive activities) [3]. These pressures have had repercus-
sions on the natural environment of the basin and its ecological diversity [20].
They have resulted in watershed degradation that has diverse and unpleasant
consequences, often resulting in increased runoff, flash floods, reduced infiltration,
erosion and siltation, to name just a few examples. The impacts of human activities
(development, rapid population growth and various productive activities) related
to the exploitation of resources for the satisfaction of the daily needs of the popula-
tions sometimes manifest themselves negatively on all the natural resources of the
basin. Environmental protection of the watershed is important for the safety and
sustainability of urban water supply. A healthy ecosystem ensures quality water for
cities, reducing treatment costs and the danger to human health.
Activities such as gold mining are causing degradation of natural resources in the
basin through reduced vegetation cover and deterioration of water quality. With the
use of chemicals in the practice of this activity (leaching technique with cyanide or
mercury and tailings ponds), pollution of water resources in the basin is multiplying.
With the major developments (Diama and Manantali dams), flow control and water
permanence in the basin have led to the partitioning of mining activities (extrac-
tion and washing with mercury release) and agricultural activities (large consumer
fertilizers and pesticides) with far-reaching consequences [21]. This results in severe
degradation and deterioration of animal and plant resources [22]. With this destruc-
tion of freshwater ecosystems, the Senegal River finds itself in a situation of loss of
some of its functions, how important, and may alter its hydrological functioning [23].
. Invasive species
Biotic factors affect water resources. For example, the presence of invasive
species such as hyacinth, Salvinia, Pistia and Typha causes ecological imbalance.
The proliferation of plants and invasive species in major bodies of water, including
aquatic plants, is of increasing concern. Typha and algae are plants that contribute
to the deterioration of the water quality of the lake because of the very toxic sub-
stances secreted that can reduce the good water quality (Figure ). They degrade
surface water resources and may even have contributed to the eutrophication of
freshwater lake ecosystems. These invasive species block rivers and greatly influ-
ence water quality. In Senegal, built dams (such as Diama and Manantali on the
Senegal River) play an important role in the reliable and sustainable supply of
water. However, these developments, by permitting the permanence and softening
of the water, have led to the proliferation of certain species such as Typha austra-
lis and Pistia stratiotes and the appearance of new species such as Potamogaton
Schweinfurthis and Ceratophyllum demersum [24]. Overall, the country faces serious
problems of resource protection.
Several environmental impacts, at the origin of the deterioration of water qual-
ity, result from the invasion of water bodies by vegetation [25]: siltation of hydraulic
axes; the formation of caps with loss of hydraulicity; increased evapotranspiration;
the threat to adjacent wetlands; the decrease of the dissolved oxygen level. The
proliferation of macrophytes can therefore make it difficult to access water, slow
down the flow of water in the canals, block the pumps.

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Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
. Interventions on the water challenges
Despite the water problems facing urban populations, Senegal has sufficient
water resources to meet demand if available resources are properly managed [6].
Senegal’s internal renewable surface water resources are estimated at 23.8km3/year
and renewable groundwater resources are in the order of 3.5km3/year. The com-
mon part between surface water and groundwater is estimated at 1.5km3/year and
internal renewable water resources estimated at 25.8km3/year [26]. The diversity
of water resources offers opportunities for exploitation ranging from surface water
abstraction to the use of boreholes in areas with limited surface water resources [10].
. Implementation of relevant policies
Like many other countries, Senegal has adopted several policies at the national
and regional levels to guide the conservation and management of its water
resources. It has put in place crucial reforms in the water sector which have led to
the promulgation of certain regulatory texts and conventions, such as Law 81-13 of
4 March 1981 on the Water Code creation of various associations of water resource
users [3]. Thus, in 1995, the public authorities give a very marked inflection to
the organization of the sector, as well in urban as rural. Indeed, a reform of the
urban water subsector was initiated through the Water Sector Project, which led
to the separation of drinking water from sanitation. This reform embodied by Law
No. 95-10 of 7 April 1995 resulted in the creation of two different entities that are
responsible for the management of the sub-sector of urban water: the National
Water Company of Senegal (SONES), a heritage company, and Senegalese Waters
(SW), operating company, private operator [6, 27].
Figure 8.
Degradation of water quality in Senegal by invasive plants: (1) Typha australis on the lake of Guiers; (2)
freshwater algae in the lake water; (3) invading lake water plan; (4) degradation of the water quality of the
lake.

Resources of Water

. Groundwater, an important additional source in urban centers
The exploitation of groundwater through wells/boreholes is widespread but
is generally not regulated or monitored in many parts of Africa. As in many cit-
ies in Africa, there is a growing demand for groundwater in Senegal’s main cities,
mainly fueled by boreholes. Senegal has groundwater resources of about 4billion
cubic meters renewable every year and all the drilling currently carried out that
pump this resource mobilizes a maximum of 6% of this resource. Thus, in terms of
water availability, Senegal is relatively well endowed, especially since this resource
is captured at depths that vary around 100m. Freshwater stored in underground
aquifers can be used effectively to divert the consequences of climate change. The
availability of groundwater resources and their replenishment rates are uncertain,
posing a serious problem for their management and protection [28]. Therefore, in
the future, improved regulation and monitoring of groundwater withdrawals, in
addition to appropriate management, will be essential for effective and sustainable
monitoring of available water resources in Senegal’s cities.
For the abstraction of groundwater in Senegal, dewatering works can be
grouped into five major systems in order of importance: boreholes and modern
motorized wells; modern wells and wells equipped with wind turbines; modern
wells and wells equipped with hand pumps; modern wells with manual or animal
drainage; traditional wells with manual or animal drainage [29]. Over the past
decades, Senegal has therefore made significant efforts on national resources and
with the support of its development partners to meet people’s drinking water needs
from groundwater. However, it must be recognized that despite the large invest-
ments, the demand for drinking water is far from being fully covered.
. Monitoring of conditioned water
In the various cities of Senegal, a good number of inhabitants use bottled water
in bottles and sachets. From tap water to the bottle, to the plastic bag, there is a
ladder of confidence in the quality of the water to drink, while the older practices of
water consumption paradoxically provoke an attachment territorial, while present-
ing a status apart, since they are detached from any commercial thought. This is
why it can be said that modern conditioning practices such as bottling and bagging
create a new image of drinking water. Calibrated or formatted through models of
different capacity, it pays off, and access is through formal and informal commer-
cial distribution networks. Bottled water is present almost everywhere, from the big
supermarket sign to the small neighborhood retailer, to the petrol stations, while
water in sachets is mostly sold in small shops, in the urban neighborhoods of Dakar
(Medina, Rebeuss …) for example, but also beyond, the capital [30].
Sachet water conditioning in Senegal is mainly in the informal sector of the
economy. Anyone who has access to tap water and owns a refrigerator can create a
“small business.” This is a common practice in working-class neighborhoods. For
modest families, it provides extra income. This ranges from bagging water in fine
and transparent plastics, without any indication of source or quality of water, to
water bags subject to prefectoral authorization with indications of the origin and
characteristics of contained water. It is the work of individual and family initiatives,
and represents an activity that involves the respect of certain health standards. The
conditioning of the water is more a practical necessity, that of providing the body
with the occasional need for water, with a taste that is supposed to be better than
that of tap water. In Senegal, its consumption reaches significant proportions. In the
streets of Dakar, at any time, it is marketed in bottles and especially in small plastic
bags, exchanged for parts of 25 or 50F CFA.Numerous, by the way, are those who


Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
have invested in this business, from children to adults, hence the importance of
setting up a structure for its supervision.
. Rainwater harvesting
There is a regional imbalance in the recovery and distribution of water, and
therefore in water security. In addition, the uneven distribution and variability of
rainfall in sub-Saharan Africa impacts the annual water availability of households.
In addition, climate change is constantly increasing extreme events such as droughts
and floods with disastrous consequences for people’s lives. Sub-Saharan Africa has
abundant rainfall, but it is not evenly distributed and highly seasonal. Senegal expe-
riences droughts and floods every year. It receives rainfall ranging from 200mm in
the dry parts (Sahelian domain) to more than 1500mm in the southern and south-
eastern parts of the country (southern Sudan) [2]. Senegal’s renewable freshwater
resources vary considerably with time and region and cannot adequately meet the
growing demand in large cities. Water harvesting could be an additional means
of alleviating the problems of drought, scarcity and depletion of water resources.
Surface water is scarce and groundwater exploitation is often not profitable. As a
result, sustainable rainwater harvesting systems can be a very important solution to
the problem of water scarcity. However, the collection of rainwater for domestic use
in cities is not sustainable due to the configuration of the building and the diver-
sity of activities that pollute the environment. However, for this rainwater to be a
solution to the permanent shortages of water currently observed, it should first be
captured and then treated before use [11].
. The construction of additional hydraulic infrastructures
Very important results were obtained during the 2005–2015 decade, marked by
the implementation of the Millennium Drinking Water and Sanitation Program
(PEPAM), both in terms of the definition of policies and strategies, the mobiliza-
tion of financing and setting up of access to services. However, there are still major
obstacles still to be overcome, including the still inefficient management of drink-
ing water quality issues due to localized pollution of certain groundwater or surface
water levels, accessibility still average water points due to the low rate of access
to water by connection to homes and the average density of distribution points in
rural areas … [7]. To remedy this, the Government of Senegal, under the Ministry
of Hydraulics and Sanitation, has launched projects to increase water infrastructure
to combat water scarcity. Such infrastructures should make it possible to increase
qualitatively and quantitatively access to water and sanitation services, promote
sustainable management of water resources, reduce the incidence of water-related
diseases, strengthen sector governance through targeted institutional support, with
a view to signing a sector budget support program.
. Strategies to address the water scarcity in Dakar
The shortage of water, temporary or structural, results from a quantitative and/
or qualitative insufficiency of the available water resource compared to the demand.
His study contributes to the reflection for a better distribution and preservation of
water. Water scarcity is a critical issue when it comes to dealing with the sustain-
able development of societies. A precise study of the different types of conflicts
observed is necessary. These occur recurrently between areas of use, commercial
and non-market water uses—in practice urban water supply and irrigation [31].

Resources of Water

Difficulties in the supply of drinking water in Dakar are also due to a poorly con-
trolled urbanization policy, which translates into a sort of “let do” in the settlement
of the populations, which proceed to anarchic constructions, in zones undeveloped.
The housing and housing crisis ended up condemning people to a frantic race to
find a piece of land [32].
To this problem is added that created by the increase in the number of consum-
ers, which aggravates an already tense situation, due to the natural increase of the
population which largely benefits Dakar and the sustained movement of immigra-
tion as well as of the rural exodus, the migrants having as their point of departure
the “low quarters,” already confronted with the precariousness of the system of
supply of drinking water. Given the increase in water demand with the high popula-
tion growth, in a context of climate change, Senegal, like many countries in the
world, is beginning to have an imbalance between its water supply and the demand
of citizens in perpetual rise. To remedy this, the different actors in charge of water
resources issues (government institutions, development partners, civil society
and the private sector) must undertake a sustainable management of the water
resources that are available on the territory.
For Lacoste [33], “In the third world countries, municipalities in big cities
must now respond to many demands for a fairer distribution of water between
rich neighborhoods and slums or slums. Some have water in abundance, while the
others, where the vast majority of the population lives, have almost none. How, in
these conditions, to make reach a maximum of populations with a drinking water?
The answer to this question lies in a significant increase in the budgets allocated to
the financing of social facilities. Having understood this, the Senegalese authori-
ties in charge of the issue have approached access to drinking water as a public
health imperative, which has become a social priority for the country. This is even
more true since the links between water and health on the one hand and water and
economic development on the other are no longer in doubt [32]. As access to drink-
ing water requires undeniable financial efforts, innovative strategies are being put
in place to enable a larger section of the population to benefit. These strategies are
based on a concerted approach that brings together non-governmental organiza-
tions (NGOs), the private sector and governments in synergy.
Dakar’s drinking water supply has long been a major problem in Senegal.
Indeed, since the 1980s, Dakar had begun to register a significant deficit in the
water supply of its population. From 4% in 1984, the deficit exceeded the thresh-
old of 30% in 1991 to reach the record level of 100,000m3/day in 1998. Thus, to
prevent this situation from becoming a disaster, Important means have been put
in place to manage this deficit, but this cannot completely solve the problem [34].
The schematic flow of the current Dakar water supply system in 2013 is illustrated
below in Table  [35].
The history of Dakar’s water supply began in 1949, when groundwater from
the sub-basaltic aquifers of Mamelles and Point B, as well as the quaternary sand
aquifers of Thiaroye, were drilled and developed. Then, in 1960, to meet the increase
in demand for water, taking into account the risks of over-pumping aquifers near
Dakar, new Paleocene limestone aquifers were exploited at Pout and Sébikhotane.
The steady rate of increase in water demand in the following years necessitated the
continued development of water resources. Consequently, in 1970, aquifers of the
Maastrichtian layer along the northern coastal zone (North Coast) were exploited
and the surface waters of the Senegal River were taken from Lake Guiers [35]. In the
absence of sufficient local drinking water resources, Dakar is supplied by a water
supply system from Guiers Lake. This system transports water from the Senegal
River to the capital over 250km and represents 50% of Dakar’s drinking water
supply [24]. The strong population growth of recent years has led to the saturation


Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
Water treatmen t
plant
Year in service Extension Nominal
capacity
(m/d)
Hourly
volume
(m/h)
Ngnith factory 1971 2000
(transition to
a theoretical
capacity of
60,000m3/d)
40,000 1667
Keur Momar Sarr
factory
2004 2008
(transition
from 65,000 to
95,000m3/d)
2011
(transition
from 95,000 to
130,000m3/d)
130,000 5417
Drilling Number
of
drilling
Year in service Extension Nominal
capacity
(m3/d)
Hourly
volume
(m3/h)
Northern littoral
drilling (Gueoul at
Ndande axis)
91999 —35,000 1591
Kelle/Kebemer
drilling
7from the 1970s —30,000 1364
Pout Nord drilling 13 from 1978 (PN6
and PN10)
—4 7,2 4 8 2148
South Pout drilling 7from 1979 (PS5) —20,000 909
Pout Kirene drilling
(including KSW)
41993 (PK3, PK5) —6000 273
Sebikotane drilling 11957 —4500 205
Thiaroye drilling 21951 Not used due to
deterioration
of water
quality
0 0
Point B/Mamelles/
Point G drilling
81966 —18,000 818
Booster Year in service Extension Nominal
capacity
(m3/d)
Hourly
volume
(m3/h)
Mekhe booster 2006 —233,557 10,155
Carmel booster 2013 —241,708 10,509
Pumping station Year in service Extension Nominal
capacity
(m3/d)
Hourly
volume
(m3/h)
Thiaroye factory 1951 —29,90 0 1300
Point B factory—
Madeleine pumping
1966 —20,700 900
Point B factory—
pumping Mamelles
2006 —64,400 2800
Point B factory—
pumping point
1966 7000 700
Transmission line Year Characteristics

Resources of Water

of production and transfer capacities. Currently, nearly 1million people in the
capital suffer from intermittent service. The Dakar region, which comprises 25% of
Senegal’s population and concentrates 80% of the country’s economic activities, has
its water needs estimated at around 320,000m3/d, which represents nearly 75% of
the total production water supply [35]. In 1993, 80% of water consumption in the
Dakar region consisted of groundwater, while the remaining 20% came from Lake
Guiers. In 2013, this ratio was reversed due to over-exploitation of groundwater [36].
To ensure an optimal water supply for the city of Dakar and fight against water
scarcity, the government has mobilized since 2014 an additional production of
100,000m3/day through the realization of 60 boreholes and the rehabilitation of
seven others. This additional volume represents 26% of the average daily produc-
tion (360,000m3). From 2014, a peak of 390,000m3/day is reached with the
commissioning of Bayakh’s new drinking water production center in July 2018. This
production is provided by the factories of Keur Momar Sarr and Ngnith installed
on the site of Guiers Lake (40%) and boreholes of the North Coast, South Pout,
Pout Kirène, Kelle-Kébémer and Dakar (60%). With the commissioning of the two
Bayakh-Thieudème-Diender and Tassette phases, additional production will reach
179,000m3/day overall, or nearly 50% of the capital’s peak needs.
Water treatmen t
plant
Year in service Extension Nominal
capacity
(m/d)
Hourly
volume
(m/h)
ALG1 (Ngnith pipe) 1971 DN 1000 PN
25 steel
ALG2 (driving
KMS)
2004 DN 1200 PN 25
cast iron
800 Sebi 2008 DN 800 cast
iron
600 discharge
Thiaroye
1951–1994 DN 600 cast
iron
700 output tanks
PTY
1951 DN 700
800 Mamelles
repression
1993 —
600 South Pout
repression
—DN 600 PN 16
steel
Tanks Year Characteristics
Tanks of Thies 1971 (R1, R2); 2005 (R3, R4) 25,000m3
Tanks Y-point 1951 10,000m3
Tanks of
Madeleines high
service
1966 1200m3
Tanks of
Madeleines low
service
1966 6000m3
Tanks of Mamelles 2003 35,000m3
Tanks of G point 1966 5000m
Source: JICA study mission based on information provided by SDE.
Table 1.
Main lines of major structures in the water supply network for the Dakar region.


Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
From January 2011 to June 2018, production increased by 22%, from 297mil-
lionL/day in December 2011 to 355millionL/day in June 2018. The peak of 439mil-
lionL/day will be reached in December 2018, i.e., +29% with the commissioning
of Bayakh and Tassette, as well as the three new boreholes of Dieuppeul, Yoff
and Nord Foire. SONES has implemented the various phases of the Emergency
Program with the SDE.Thanks to the impact of this work, the deficit neighbor-
hoods had better access to the drinking water service: Nord Foire, Ouest Foire,
CPI, Cité Alternance, Scat Urbam, Grand Yoff, Liberté 6 extension, Mixta, Keur
Damel, Socabeg, Cité Léopold Sédar Senghor, Hlm Grand Yoff, part of the Unit
26 of Parcelles Assainies, Toubab Dialaw. In 2017, the Ministry of Hydraulics and
Sanitation has developed the Special Program for Drinking Water Supply in Dakar
(PSDAK) which is an intermediate solution pending the completion of structural
works such as: the third production plant and Keur Momar Sarr drinking water
treatment (KMS3) and the des Mamelles seawater desalination plant in Dakar.
The PSDAK has two phases that aim to strengthen production, improve the
quality of the water distributed and secure the supply of electricity. The first phase
of the PSDAK consists of hydraulic works at Bayakh, covering a battery of five
new boreholes, a pumping station, a storage tank of 1500m3 and an adduct line of
18.6km between Bayakh and Rufisque. It has allowed a production of 15,000m3/
day which is injected into the network and several deficit areas have better access
to drinking water in 2018. The second phase of this program consists in particular,
of six boreholes, a station of pumping, a reservoir and a large diameter transfer line
on the axis Diender-Thieudème. Ultimately, these structures will bring a volume of
water of 15,000m3/day complementary.
Apart from additional drilling, and social connections provided by SONES, the
KMS 3 and the des Mamelles water desalination plant are the keystones of a water
security policy. This option will consolidate production and preserve the capital
and the Small Coast from any water stress until 2035. These two major projects of
the state are committed to the challenge of water, in the perspective of population
growth established at 3% annually. The third Keur Momar Sarr plant (KMS 3)
should cover the drinking water needs of the Dakar populations, the new urban
center of Diamniadio, the Rose Lake, as well as all the localities crossed by the Lac
de Guiers pipeline from 2021 It is expected to represent in 2020 more than 20% of
the drinking water supply capacity of the water supply system from Guiers Lake. As
for the other structuring project that is the Mamelles seawater desalination plant,
with a capacity of 50,000m3/day expandable to 100,000m3, the water problems of
Dakar will be conjugated to the past.
In order to ensure the supply of water to cities, it is therefore essential to improve
the availability of sustainable water supply, the conservation and restoration of
water bodies as well as strategic investments in additional water infrastructures.
Additional water facilities would help increase water storage capacity for long-term
uses and avoid recurring disasters such as scarcity. In addition, urban water and
sanitation companies should prioritize the construction of efficient wastewater
treatment plants to facilitate the treatment and reuse of water.
. Conclusions
In the face of strong urban growth in Africa as a whole, people’s water supply is
often lagging behind. Many African cities find it difficult to provide adequate water
services to the growing number of occupants. The demand for clean and adequate
water is increasing due to population growth and the global obligation to achieve

Resources of Water

the Sustainable Development Goals, including Goal 6: “Ensuring access for all to
water and sanitation services managed sanitation” [37].
Senegal suffers from a chronic water crisis due to various causes including
drought, landscape degradation, floods, contamination and unprecedented popula-
tion growth. If solutions exist against mismanagement and water pollution, the
main problem lies in the frequency and severity of extreme events such as droughts
and floods due to ongoing climate change, phenomena that will likely be more
unpredictable in the future. Adequate provision of drinking water to populations
could also be strongly influenced by environmental pollution. Therefore, to pre-
serve water security, it is necessary to focus on the protection of sources, the more
judicious use of fertilizers and pesticides, the reduction of domestic and industrial
pollution as fundamental elements of the complete water management strategy.
In order to achieve the Sustainable Development Goals (SDG 6in particular),
new strategies for the sustainable management of water resources are needed. In
fact, in urban areas that use large quantities of water (which also puts a lot of pres-
sure on the country’s resources), the modernization of water infrastructure is an
important step to implement for the sustainable preservation of water. Pure water.
These strategies must also take into account the improvement of access and access
to drinking water, the fight against waste of the resource, the treatment and reuse
of water used for agricultural purposes, the storage of water in period of rainfall
abundance and its reuse in times of scarcity, preservation of aquatic ecosystems.
On the issue of the recurring water shortage in Dakar, it is recommended a
device with the following objectives: to reinforce the hydraulic equipment; reduce
the vulnerability of people and goods; appreciate, treat and reduce the risk of water
scarcity; put in place the required prevention, response and recovery measures;
maintain essential activities and services; identify external actors and integrate
them into the planning process.
Acknowledgements
We thank all the national and international organizations that provide us with
the data that helped write this article.
Conflict of interest
There are no conflicts of interest for this document.
Notes/thanks/other declarations
There are no other notes/thanks/statements.


Water Resources and T heir Management in an Increasing Urban Demography: The Case…
DOI: http://dx.doi.org/10.5772/intechopen.90218
Author details
CheikhFaye
Department of Geography, U.F.R.Science and Technology, UASZ, Laboratory of
Geomatics and Environment, Ziguinchor, Sénégal
*Address all correspondence to: cheikh.faye@univ-zig.sn
© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms
of the Creative Commons Attribution License (http://creativecommons.org/licenses/
by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,
provided the original work is properly cited.


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