The Sustainable City in Africa Facing the Challenge of Liquid Sanitation E-Book
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- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
This book questions the role of liquid sanitation in the development of cities in Africa. The absence of sewerage networks and treatment plants in African cities already submerged by rapid and anarchic urbanization is a major problem. To meet this challenge, it is urgent to rethink urban water governance and impose and enforce sustainable urban planning standards. In other words, sanitation issues must now be placed at the heart of urban planning.
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Veröffentlichungsjahr: 2023
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Table of Contents
Cover
Title Page
Copyright Page
Introduction
Acknowledgments
1 Sustainable Cities and Domestic Wastewater Treatment: The Case of Africa
1.1. Setting the context
1.2. Theoretical framework: the sustainable city in Africa
1.3. Methodological framework
1.4. Prospects for changes to be implemented
1.5. Conclusion
1.6. References
2 The National Sanitation Policy in Tunisia: Successes and Limitations
2.1. Introduction
2.2. Urban liquid sanitation: Tunisia is ahead of the countries in the region
2.3. Wastewater treatment plants, a new polluter?
2.4. The necessary readjustments
2.5. Conclusion
2.6. References
3 Cameroon’s National Liquid Sanitation Strategy: Critical Analysis and Proposals
3.1. Background
3.2. Methodology
3.3. Theoretical framework
3.4. Results
3.5. Conclusion
3.6. References
4 State of Play of Non-Collective Sanitation in Cameroon and Compliance Solutions for Sustainable Urban Planning
4.1. Introduction
4.2. Methodology
4.3. Results
4.4. Discussion
4.5. Conclusion
4.6. References
5 Industrial Water Management in Sarh (Chad): Spatialization of Socio-Environmental Risks
5.1. Introduction
5.2. Methods
5.3. Results
5.4. Discussion
5.5. Conclusion
5.6. References
6 Summary Diagnosis of the Excreta and Domestic Wastewater Collection System in the District of Douala III (Cameroon)
6.1. Introduction
6.2. Contextual framework of the study
6.3. Data collection
6.4. Results and discussions
6.5. Conclusion
6.6. References
7 The Public Sewerage System in the District Municipality of Douala I: Status of the Issue and Some Technical Guidelines
7.1. Introduction
7.2. Theoretical framework: the concept of a sanitation network
7.3. Results
7.4. Conclusion
7.5. References
Websites
Conclusion Public Sanitation Services: A Priority for Any Sustainable City Project in Africa
List of Authors
Index
Other titles from ISTE in Science, Society and New Technologies
End User License Agreement
List of Tables
Chapter 2
Table 2.1. Development of sanitation infrastructures in Tunisia
Table 2.2. Sanitation in Tunisia, an increasingly efficient sector
Chapter 4
Table 4.1. Distribution of latrine types in the Yaoundé V district
Table 4.2. Distribution of latrines according to their distance from a wate...
Table 4.3. Comparison of contamination control parameters according to the ...
Table 4.4. Comparison of physico-chemical and bacteriological parameters ac...
Table 4.5. Comparison of pit depths with surrounding wells
Table 4.6. Characteristics of filling materials
Chapter 5
Table 5.1. Water withdrawal from the Chari River by the CST in March 2013....
Table 5.2. Quantity of water per ton of cane washed at CST in March 2013.
Table 5.3. Wastewater discharges by the CST in March 2013.
Chapter 6
Table 6.1. Summary of heads of households interviewed by neighborhood
Table 6.2. Typology of land parcels in Douala III
Table 6.3. Estimated amount of wastewater produced in Douala III and specif...
Table 6.4. Estimated amount of wastewater produced in Douala III and specif...
Table 6.5. Domestic wastewater treatment plants in Douala III (Sanitation M...
Chapter 7
Table 7.1. Estimated data of the existing sewerage system
Table 7.2. Classification of the type of habitat according to the latrines ...
Table 7.3. Data on occupied surfaces with residential dominance
Table 7.4. Data on occupied surfaces with a predominantly commercial charac...
Table 7.5. Measurements of the piezometric load in the district municipalit...
List of Illustrations
Chapter 2
Figure 2.1. Anarchic discharges of untreated industrial effluents into the sea...
Figure 2.2. Leaks and anarchic discharges of poorly treated wastewater in the ...
Figure 2.3. On the beach of Ksibet El Médiouni, the pollution linked to the di...
Figure 2.4. Dead fish at Ksibet in the Bay of Monastir
Figure 2.5. Beaches closed to swimming in 2013 due to pollution from wastewate...
Figure 2.6. Popular march against marine pollution in Ksibet
Chapter 3
Figure 3.1. Eutrophication phenomenon observed in the Wouri River (Douala). Fo...
Chapter 4
Figure 4.1. General operating principle of a biological treatment plant
Figure 4.2. Some organic pollutants produced by wastewater
Figure 4.3. Linear extrapolations of total coliform and fecal coliform values ...
Figure 4.4. Distances required in the installation of a stand-alone system
Figure 4.5. Diagram of the layout of collective and non-collective sanitation ...
Figure 4.6. Diagram and recommendations for a ventilated watertight pit
Figure 4.7. Diagram of an ECOSAN latrine
Figure 4.8. Characteristics of a septic tank
Figure 4.9. Drained filter bed and installation rules
Figure 4.10. Reception area for septage
Figure 4.11. Diagram of a treatment facility for septage using reed beds
Chapter 5
Figure 5.1. Location of the city of Sarh
Figure 5.2. Location of the industrial units studied in Sarh
Figure 5.3. Main building of the Sarh regional hospital
Figure 5.4. CST lagoon for the collection and treatment of industrial water
Figure 5.5. Water management system at the Sarh regional hospital
Figure 5.6. Control panel for the regional hospital’s wastewater treatment pla...
Chapter 6
Figure 6.1. Location of the Douala III district and survey areas
Figure 6.2. Structure of the neighborhoods in the Douala III district
Figure 6.3. Example of high-quality housing in the Dibom II district
Figure 6.4. Low-standard housing in the neighborhoods of Moutongo
Figure 6.5. Domestic wastewater collection infrastructure
Figure 6.6. Traditional latrine with a shower area
Figure 6.7. Traditional bottomless latrine
Figure 6.8. Installation of latrines along a watercourse in the Kolmintag neig...
Figure 6.9. Latrine with Leaky Pit in the Nyalla neighborhood
Figure 6.10. Example of an improved toilet (A: English-style toilet, B: Turkis...
Figure 6.11. Septic tank with two functional compartments: (A) with a visitng ...
Figure 6.12. Abusive discharge of gray water in the Bilongué block 3
Figure 6.13. Wastewater discharge method in households in the study area
Figure 6.14. CCC wastewater treatment plant: baffle decanter on the left and c...
Figure 6.15. Untreated effluent from the Complexe Chimique Camerounais (CCC) d...
Figure 6.16. Case of a blocked gutter in the Brazzaville district
Figure 6.17. Double concrete pipes at Mbanga Bakoko (4.00438 N; 9.79516 E)
Figure 6.18. Tongo Bassa drain transformed into a dumping ground
Figure 6.19. Partial obstruction of a culvert in the Mgoua River by a garbage ...
Figure 6.20. Culvert of the Ndogsimbi branch under Avenue Roger Milla, in a pl...
Figure 6.21. Flooded road due to ineffective stormwater structures
Figure 6.22. Type of malfunctioning of sewage works in the study area
Figure 6.23. Prevalence of diseases encountered in the study area
Chapter 7
Figure 7.1. Geographical location and neighborhoods of Douala I
Figure 7.2. Overview of a longitudinal cross-sectional view
Figure 7.3. Collectors for boulevard Sébastopol, around 1900
Figure 7.4. Structuring of spontaneous and structured areas in Douala I
Figure 7.5. Neighborhood of Douala I with a strong domination of structured ar...
Figure 7.6. Neighborhoods of Douala I with a strong domination of semi-structu...
Figure 7.7. Neighborhoods of Douala I with a high domination of unscreened are...
Figure 7.8. Neighborhoods of Douala I with a high domination of very dense inf...
Figure 7.9. Comparison of buried networks under asphalt and non-asphalt roads
Figure 7.10. Neighborhoods with high residential density
Figure 7.11. Neighborhoods with high commercial influence
Figure 7.12. Neighborhoods with high administrative functionality
Figure 7.13. Geomorphology of Douala I
Figure 7.14. Level curves of surface water passage in Douala I
Figure 7.15. Map of the piezometric curves of Douala I
Figure 7.16. Available area in Douala I that can accommodate the pumping stati...
Guide
Cover Page
Title Page
Copyright Page
Introduction
Acknowledgments
Table of Contents
Begin Reading
Conclusion: Public Sanitation Services: A Priority for Any Sustainable City Project in Africa
List of Authors
Index
Other titles from ISTE in Science, Society and New Technologies
WILEY END USER LICENSE AGREEMENT
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Territory Development Setcoordinated byAngela Barthes
Volume 2
The Sustainable City in Africa Facing the Challenge of Liquid Sanitation
Edited by
Esoh Elamé
First published 2023 in Great Britain and the United States by ISTE Ltd and John Wiley & Sons, Inc.
Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers, or in the case of reprographic reproduction in accordance with the terms and licenses issued by the CLA. Enquiries concerning reproduction outside these terms should be sent to the publishers at the undermentioned address:
ISTE Ltd
John Wiley & Sons, Inc.
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UK
USA
www.iste.co.uk
www.wiley.com
© ISTE Ltd 2023The rights of Esoh Elamé to be identified as the author of this work have been asserted by him in accordance with the Copyright, Designs and Patents Act 1988.
Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s), contributor(s) or editor(s) and do not necessarily reflect the views of ISTE Group.
Library of Congress Control Number: 2022945776
British Library Cataloguing-in-Publication Data
A CIP record for this book is available from the British Library
ISBN 978-1-78630-808-5
Introduction
This book, rich in lessons learned, contributes to a better understanding of the current realities of domestic wastewater collection and treatment in African cities. As a reminder, in urban hydraulics, wastewater refers globally to water that has been soiled by use. The purpose of collective or non-collective liquid sanitation is the removal and treatment of wastewater.
There are two types of wastewater: domestic wastewater and industrial or agricultural effluent1. Domestic wastewater refers to black water (toilet water) and gray water (water from the sink, kitchen, washing machine, etc.) from households. Industrial or agricultural effluent is wastewater from industrial or agricultural facilities.
Wastewater, whatever its nature, cannot be discharged into any ecosystem, because it causes pollution that is harmful to the environment. It therefore needs to be treated beforehand to prevent pollution risks. Carried out in a wastewater treatment plant in a collective sanitation zone, or by means of autonomous devices in a non-collective sanitation zone, the treatment enables the elimination of solid matters and substances dissolved in the wastewater.
At least four out of five African cities do not have urban governance for taking into account the “right to water and sanitation”. These cities have yet to institute structural changes in their planning and management to better overcome the barriers that prevent all their citizens from having access to safe water and adequate sanitation services. This situation is a sign of a lack of global vision of sanitation in African cities. It prevents the proper achievement of the Sustainable Development Goal (SDG) 6 on access to clean water and sanitation for all. The lack of transformative actions that originate from a comprehensive vision embodied in urban planning in most African cities does not ensure access to water and sanitation for everyone. Most of these African cities have several inconsistencies in urban governance that make them lose sight of the fact that sustainable resource management is one of their main missions. They have the responsibility to initiate and carry out urban liquid sanitation projects that are part of a common framework for sustainable cities driven by MDG 11.
The implementation of a set of actions concerned with liquid sanitation in African cities requires a clear vision of the objective to be reached in this field. In several African countries, the ongoing decentralization process gives municipalities wider prerogatives in several areas, including sanitation, land use planning, urban planning, management of the urban environment, social, cultural and economic development, etc. The implementation of sustainable development objectives, which cannot be achieved without a major mobilization of local authorities, necessarily requires the resolution of liquid sanitation problems in both urban and rural areas.
All African cities suffer significant economic damage every year, caused by the lack of sanitation2. Urban areas in Africa are now the focus of the major ecological, societal and economic challenges of our century in terms of sanitation. With the demographic explosion of the continent in a context of random and rapid urbanization, more than 90% of African cities still do not have a public sewerage system. However, the latter constitutes an urban heritage, which is essential for the existence of a public sanitation service in a territory. The problems of wastewater and rainwater collection caused by the absence of sewerage networks and treatment plants that comply with international standards in terms of public health generate significant direct health consequences for the populations. They can lead to premature death and significant health expenses for populations which are already poor.
The crucial lack of rainwater drainage, collection and treatment infrastructures in African cities in general and sub-Saharan cities in particular is no longer acceptable in terms of hygiene and salubrity. The wastewater with its numerous materials and substances is directly discharged into the natural environment, causing significant pollution. This deplorable situation makes African and sub-Saharan cities particularly vulnerable, constantly faced with the appearance of epidemics and the degradation of the environment and living conditions of the populations.
Most African cities, due to the lack of urban planning in line with sustainable urban development standards, have not been designed to ensure that all their households have systematic access to adequate liquid sanitation services. Liquid sanitation in sub-Saharan cities and related hygiene issues have long been neglected and are now confronted with high population growth, uncontrolled urbanization and the proliferation of slums, which is the expected effect of poor urban development.
Given the seriousness of their liquid sanitation problems, sub-Saharan cities are obliged to make this a central point of their urban planning. To this end, the installation of sanitation systems and the education of urban populations on the risks associated with the discharge of wastewater in the open air or in channels reserved for rainwater are some of the urgent actions to be taken. Decision-makers in sub-Saharan cities must understand the importance of setting up adequate sanitation facilities. This is all the more urgent since in many countries, economic and demographic growth as well as urbanization will increase the demand for decent sanitation facilities. Thus, defining a framework in each sub-Saharan city for the provision of sustainable sanitation services on a large scale, accessible to all, is a major challenge.
In sub-Saharan African cities, liquid sanitation is one of the main obstacles to local development. The situation of African cities, especially in sub-Saharan Africa, with regard to liquid sanitation, is very worrying and calls for urgent action. African cities cannot develop without putting a special emphasis on liquid sanitation issues, neither is their eventual transition to sustainable cities possible without a convincing approach to managing their current sanitation problems. It is also clear that the implementation of a Local Agenda 21 approach in a sub-Saharan city could be an appropriate framework for a broad consultation aimed at finding long-term solutions to the liquid sanitation problem. The orientations traced by the Local Agenda 21 approach make it possible to experiment with a participatory urban planning process that takes liquid sanitation into account.
In sub-Saharan countries, it is noted that the key components of the sanitation framework are poorly defined. There is a lack of public policies on sanitation that leads to the clear and precise implementation of guidelines that result in the provision of adequate and hygienic sanitation services. Technical modalities, accompanied by a well-harmonized financing system and well-targeted incentives to support the provision of adequate sanitation services are not in place in sub-Saharan cities. Sub-Saharan countries are slow to learn from the experience of Asian countries that were in the same situation as them, but were able to implement large-scale sanitation projects.
This book presents, in a general way and through the prism of the sustainable city, the problem of liquid sanitation in African human settlements from a few case studies: from Tunisia, Cameroon and Chad. The rapid and uncontrolled urbanization in African cities shows that the time for the application of improvised, distorted and simplistic solutions to liquid sanitation is over. It is no longer possible to think about the city in Africa without a strong focus on liquid sanitation facilities and the public service that results from them, especially since they have a direct impact on the quality of life and health of citizens. African cities, like all cities in the world, need solutions to the problem of liquid sanitation that are successfully integrated into the solutions adopted for sustainable urban planning.
Divided into seven chapters, this book addresses the issue of liquid sanitation as one of the components of the right to water and sanitation. The first chapter of the book, written by Esoh Elamé of the University of Padua (Italy), sets the scene by addressing the issue of “Liquid sanitation in African cities when faced with the challenges of the sustainable city”.
The second chapter focuses on national liquid sanitation policies in Tunisia. The author Rebei Hedi, from the University of Sfax, gives us an overview of the Tunisian situation in the field of sanitation. The creation of the National Sanitation Office (Office National de l’Assainissement, ONAS) in 1974 to ensure the preservation of water resources has been decisive. It can serve as an example to other African countries.
In Chapter 3, Esoh Elamé provides a critical analysis of strategic planning for liquid sanitation in Cameroon.
Chapter 4, written by Esoh Elamé and Jacques Martel, discusses the inadequacies of non-collective or autonomous sanitation in Cameroon.
In Chapter 5, Yamingué Bétinbaye, Ngaressem Goltob Mbaye and Michel Tchotsoua address the issue of industrial water management in Sarh (Chad), particularly its impacts in terms of spatialization of socio-environmental risks.
Subsequently, in Chapter 6, Esoh Elamé, Moni Augustine Nathalie, Tefounou Marco Bianny and Jacques Martel talk about wastewater management in the Douala 3 district.
Chapter 7 deals with the public sewer system in the Douala 1 district municipality. Akini Damsou, Esoh Elamé and Jacques Martel analyze Douala 1 and show that this municipality meets all the parameters for a public sewer system that can provide good wastewater collection and treatment.
In the light of the information provided by these various studies, it can be concluded that the problem of domestic wastewater is a major urban challenge in Africa today and for at least the next three decades. Public liquid sanitation services, currently unknown in most African cities, must be promoted. It is no longer acceptable to have cities in Africa where local officials and elected representatives do not take up the issue of setting up and monitoring the wastewater collection and transport network in addition to the treatment plant in order to maintain and permanently check their efficiency. Each African city should have its own wastewater network and connection plan and should have the means to better manage its wastewater. Unless African countries make consistent and significant long-term investments in public liquid wastewater systems, sustainable urban development of their cities will not be possible.
Notes
Introduction written by Esoh ELAMÉ.
1
Effluents of industrial or agricultural origin.
Industrial and agricultural activities generate wastewater: water used in a manufacturing process, water used to rinse manufactured products, water used to wash workshops or livestock buildings, etc. Their treatment is the responsibility of the industrial or agricultural operator. It is therefore recommended that the operator acquires the appropriate equipment for the treatment of wastewater. The operator can also have a contract with a wastewater treatment plant in a nearby municipality. When the wastewater is too polluted to be treated, it must be disposed of as hazardous waste (i.e. sent to a specialized treatment center).
Source: https://www.eaufrance.fr/lassainissement-des-eaux-usees-domestiques.
2
As a reminder, a sewerage system in a city is public and is part of the urban hydraulic system. It is a public facility whose purpose is to collect wastewater and rainwater from a specific area with the major concern of protecting the natural environment. Perfectly watertight, both for the wastewater carried away inside the pipes and outside, in order to avoid the introduction into the water pipes contained in the ground, even in the case of ground movements; the sewerage system is built to last over time. The implementation of a sewerage system requires main and ancillary works. The main works correspond to the development of the whole network up to the entry of the effluents in the treatment plant and their explosion to the outlet. The pipes are used according to the size of their section; they are classified as main collector for large diameters greater than ᴓ800, secondary collector for diameters between ᴓ400 and ᴓ800 and tertiary collector for diameters less than or equal to ᴓ300. The sewerage network also includes ancillary works which are made up of all the connection, access, wastewater reception and stormwater engulfment devices and installations whose functional role is to enable good and efficient operation of the network, in particular storm overflows, liftings, storage-restitution basins, etc. A sewerage system includes structures that are designed and calculated to resist permanent loads and rolling overloads from vehicles on the public highway. The pipe material is also supposed to resist external and internal corrosion due to the nature of the wastewater.
To learn more, refer to:
Goubert, J.P. (1984). La France s’équipe. Les réseaux d’eau et d’assainissement. 1850–1950. Les annales de la recherche urbaine, 23(1), 47–53. Persée-Portail des revues scientifiques en SHS.
Scherrer, F. (1992). L’égout, patrimoine urbain : l’évolution dans la longue durée du réseau d’assainissement de Lyon. Doctoral Dissertation, Université Paris-Est Créteil Val de Marne (UPEC).
http://hydrauliqueformation.blogspot.com/2013/03/canalisation.html.
Acknowledgments
The work by the authors of this book is part of the European project “Masters in Environmental Science - Mention: Integrated Management of the Water Resources and Sanitation in African Cities” (ref. FED/2011/276626) funded by the European Commission, within the framework of the European “Water Facility” program.
However, the contents of this book are the sole responsibility of its authors. The responsibility for this material lies with its principal authors and does not represent the opinion of the European Commission, which is not responsible for any use that may be made of the information contained therein.
1Sustainable Cities and Domestic Wastewater Treatment: The Case of Africa
1.1. Setting the context
Domestic wastewater treatment is a central issue in the environmental and health problems of African cities, regardless of their size. In more than 90% of African cities, there is a lack of liquid sanitation systems and if they do exist they are inadequate. Access to decent liquid sanitation through the existence of a public sewerage system that complies with hygiene and sanitation standards is a luxury for both poor and rich populations.
The lack of wastewater sanitation in African cities can only hinder their sustainable development. Taken as a whole, African cities, particularly in sub-Saharan Africa, are experiencing several problems with regard to the quality of their urban fabric in terms of hygiene and sanitation. The recurrent problems of wastewater sanitation in African cities are a health concern. The absence of a public sanitation service generates mistrust and discontent among users.
This contribution aims to clearly pose the problem of domestic wastewater treatment in African cities, which are at the crossroads of economic, social and environmental issues for the African States. The transforming action of globalization paves the way to question the environmental problems of African cities. In order to balance priorities, sub-Saharan cities are looking for better ways to solve their perennial liquid sanitation problem. As the populations have been demanding for some years, these cities need effective solutions in the field of hygiene and sanitation to be integrated into their urban planning. Thus, in terms of urban development, no African city will be able to claim to be in line with MDG Goal 11 without effectively solving its liquid sanitation problems. A better balance must be sought between urban planning, liquid sanitation and sustainable cities. Under the impetus of the State’s regulatory functions, urban planning for the sustainable city in sub-Saharan African countries can generate a creative and productive dynamic of good practices in liquid sanitation mobilizing the populations. Triggering the sustainable city process in sub-Saharan Africa can produce a balance that would reconcile economic growth, social progress and environmental protection. This chapter intends to propose a constructive vision of the liquid sanitation problems of African cities.
Today, in most sub-Saharan cities, domestic wastewater sanitation has an impact on the population’s quality of life and on other urban issues. Despite this, political leaders and senior civil servants are failing to provide their cities with public wastewater services that meet international hygiene and sanitation standards. Most of these political leaders and senior civil servants are not yet aware of the 2010 United Nations General Assembly resolution that recognizes the right to safe drinking water and sanitation as a human right. These decision-makers are then called upon to make greater efforts to provide their populations with accessible and affordable drinking water and sanitation services. It is also noted that these decision-makers have not yet realized Target 6.2 of the MDGs, which calls for ensuring equitable access to adequate sanitation services for all.
These decision-makers continue to postpone the major decisions they should have taken decades ago regarding the establishment and management of public liquid sanitation services. The safety, health, individual and collective well-being of African populations are at stake. The repercussions of the degradation of the urban environment in sub-Saharan cities due to liquid sanitation problems induce significant public and private expenses in the public health sector. In the medium and long terms, they will generate huge costs in terms of depollution, health costs, loss of human capital, etc.
Box 1.1. Key facts. https://www.who.int/fr/news-room/fact-sheets/detail/sanitation
In 2017, 45% of the world’s population (3.4 billion people) had access to improved sanitation facilities, allowing excreta to be disposed of on-site or treated off-site safely.
31% of the world’s population (2.4 billion people) had access to private sewage facilities connected to main sewers with treated wastewater.
14% of the world’s population (1 billion people) used toilets or latrines with on-site excreta disposal.
74% of the world’s population (5.5 billion people) had access to at least one basic sanitation facility.
Some 2 billion people still do not have toilets or latrines.
Of these, 673 million defecate in the open, such as in gutters, behind bushes or in water bodies.
It is believed that at least 10% of the world’s population consumes food from crops irrigated with wastewater.
It is estimated that there are about 36 million hectares of cultivated land in peri-urban areas irrigated by urban wastewater, usually untreated. This is equivalent to the size of Germany.
Poor sanitation is linked to the transmission of diseases such as cholera, diarrhea, dysentery, hepatitis A, typhoid and polio and exacerbates stunted growth.
Poor sanitation reduces human well-being and hinders social and economic development through consequences such as anxiety, risk of sexual assault and reduced educational opportunities.
It is estimated that poor sanitation is responsible for nearly 432,000 deaths from diarrheal diseases. It is a major factor in the spread of several neglected tropical diseases, including intestinal parasites, schistosomiasis and trachoma. It also contributes to malnutrition.
Today, in many sub-Saharan cities, the poor understanding of sanitation issues by senior officials and policy makers is compounded by the fact that short-term economic interests are more important than the protection of the urban environment. Awareness of environmental problems and their protection through significant investments remains a luxury. The aim of this chapter is to show the urgency of intervening in favor of liquid sanitation in African cities, in a context where anarchic urbanization governs urban development. In the same way, and still in the logic of the practicability and impact of sustainable development in African cities, it is necessary to ask how liquid sanitation problems can lead to changing current urban planning practices.
1.2. Theoretical framework: the sustainable city in Africa
Data from the United Nations and the World Bank are clear: Africa is urbanizing very rapidly. Moreover, this urbanization is of variable geometry, in a context where the increase in poor populations leads them to invent solutions for their survival in the face of the absence or little impact of public policies for the redistribution of wealth.
In the current state of legislation on urban planning in several African countries, we can only expect an acceleration of lawless urbanization. State officials have not taken drastic measures to impose dynamic, interactive territorial planning in their cities, which would prevent urban sprawl. The agents of the central administration, as well as the local elected representatives, remain timid and unimaginative in breaking with the old habits of multiple origins that encourage lawless urbanization. They are struggling to adopt a participatory, inclusive and endogenous decision-making process that will promote local development leading to a sustainable city.
As such, the change to be made in order to employ measures guaranteeing the establishment of sustainable cities remains very problematic. With regard to current public policies on urban planning, most African cities are totally out of step with the principles and indicators of sustainable urban development.
The emergence of the concept of sustainable development at the Rio Conference in 1992, as defined in the Brundtland report and whose implementation is prescribed in Agenda 21, introduced the era of strategic planning for territories (cities and countryside). It is worth noting here that this concept has not yet been fully understood and integrated into public urban development actions in African cities. Although some rare cities are exceptions by having a Local Agenda 211, it is important to remember that for the most part, everything remains to be done. The urban transformation that leads to the sustainable city requires a clear vision to define a framework and generate opportunities to improve the urban fabric, which is currently lacking in most African cities.
Conditions must be created to operationalize a new conception of development planning and analysis in African cities. “The achievements of the implementation of a Local Agenda 21 approach remain understated in cities in industrialized countries and very insignificant in cities in developing countries” (Esoh Elamé 2016) and particularly in Africa. The sustainable city notion emphasizes the consideration of sustainable development in territorial policies (Esoh Elamé 2016, p 13).
In fact, among the 55 member states of the African Union in 2020, including the Sahara, which Morocco does not recognize as an independent country, the bitter observation is that the concept of the sustainable city remains unknown to elected officials and senior managers of ministries and local authorities. Very little effort is made by local decision-makers in African cities to put into practice the recommendations of Chapter 28 of Agenda 21 (Global Agenda 21 from the Rio Conference) requiring all local authorities in the world to establish a dialogue with their inhabitants, local organizations and private companies in order to adopt an Agenda 21 program at the community level, commonly called Local Agenda 21. It is the development of this urban planning document that initiates the process of establishing a sustainable city through a planning document called Local Agenda 21.
In Chapter 28 of Agenda 21 (United Nations Global Agenda 21) entitled “Local Authorities’ Initiatives in Support of Agenda 21”, it is stated that:
Local authorities construct, operate and maintain economic, social and environmental infrastructure, oversee planning processes, establish local environmental policies and regulations, and assist in implementing national and subnational environmental policies (UNCED 1993, p. 202).
Agenda 21 thus highlights the key role that cities have to play in making sustainable development in an urban context a real global challenge. It is also clearly mentioned in this document that cities “play a vital role in educating, mobilizing and responding to the public to promote sustainable development” (UNCED, op cit). Agenda 21 formulated in its Chapter 28 a set of objectives concerning local authorities, namely:
1) by 1996, most local authorities in each country should have undertaken a consultative process with their populations and achieved a consensus on “a local Agenda 21” for the community;
2) by 1993, the international community should have initiated a consultative process aimed at increasing the cooperation between local authorities;
3) by 1994, representatives of associations of cities and other local authorities should have increased levels of cooperation and coordination with the goal of enhancing the exchange of information and experience among local authorities;
4) all local authorities in each country should be encouraged to implement and monitor programs which aim at ensuring that women and youth are represented in decision-making, planning and implementation processes.
This document is an indispensable tool for urban planning and territorial forecasting. It calls into question the improvised urban management, the day-to-day management of a territory which characterizes most African cities. The Local Agenda 21, based on the aspirations of the population and the real needs of the territory, constitutes a framework that makes it possible to organize intentions and prioritize them. The construction of such a planning framework for collective action is today the reference in terms of good territorial governance.
Action 21, as the first global Agenda 21, has therefore put in place specific mechanisms to support the anchoring of sustainable development in cities. Agenda 21, in addressing the issue of sustainable development in an urban context, was inspired by the work on access to housing for all of the United Nations Center for Human Settlements (UNCHS)2, also called Habitat at the time, which later became UN-Habitat.
In general, it is worth noting that African cities are not succeeding, for various reasons, in following the framework set out in Chapter 28 of Agenda 21 to promote well-defined local public policies for urban renewal, centered on sustainable development. We do not see any concrete liaison actions at the African, sub-regional or even national level for the application of sustainable development principles in the cities of African countries just after the 1992 Rio conference. Immediately after the 1992 Rio conference, no African country had made a strong commitment to promote endogenous urban governance based on urban planning, with particular emphasis on liquid and solid sanitation issues. A few years later, the first African country to take initiatives to promote Local Agenda 21 and strengthen its institutional capacities in this area was Tunisia. Subsequently, other North African countries have timidly initiated the process. In sub-Saharan Africa, apart from South Africa, the mobilization of governments and their local authorities in the territorial anchoring of the concept of sustainable city remain null more than 25 years after the dissemination of Agenda 21. Thus, in these countries, the activities carried out by the States, notably on housing, infrastructure, water supply, basic services, land use planning, the environment, disaster management, public finance, municipal management and safety in the cities, are not part of a territorial planning aimed at building sustainable cities. Thus, more than a quarter of a century after the global popularization of sustainable development, we are struggling to see concrete public policies in sub-Saharan countries aimed at increasing urban planning capacities for sustainable cities.
In the framework of both the International Union of Local Authorities (IULA) and the International Council for Local Environmental Initiatives (ICLEI) initiatives, it is difficult to see sub-Saharan cities mobilizing with determination to adopt good practices in environmental and sustainable development.
The New Urban Agenda3, which was adopted at the UN Conference on Housing and Sustainable Urban Development (Habitat III) in Quito, Ecuador, on October 20, 2016 has not led to any movement in African urban planning for sustainable cities. Although it focuses its attention on urban renewal, and especially on improving living conditions in disadvantaged neighborhoods, the New Urban Agenda so far has not triggered a significant increase in urban planning based on the sustainable city where sanitation is central to urban renewal.
Since 1998, Africities, which takes place every three years in one of the five regions of the continent, is indisputably the flagship pan-African event that brings together a large number of African local authorities as well as financial institutions, civil society organizations and development partners at the continental and international levels. This initiative has not succeeded in focusing the debate within African local authorities on the concept of sustainable cities and their anchorage in African cities.
The sustainable city concept is slow to emerge in Africa. It is fundamentally a question of African cities becoming aware of their failure in terms of urban planning, particularly with regard to their capacity to offer their citizens a vision of the inclusive, intercultural, environmental and intelligent city. It is therefore important to reframe public urban development policies in African countries by making cities the object and subject of reflection on urban planning. Transforming the city into a space for permanent discussion on land use planning in order to overcome all forms of poverty, reduce social, cultural and environmental inequalities and to promote resilience is now an imperative.
The urgency of transforming African cities into a vast pan-African construction site for inclusive, sustainable urban spaces is therefore quite acute. It is now necessary to pose the problem and implore decision-makers to become aware of it. The latter can no longer leave to future generations the vast task of restructurning urban policies geared to sustainable development. It is now important to build sustainable cities in Africa through an inclusive, participatory, endogenous, intercultural, environmental and pan-African approach.
It should also be noted that the exponential demographic growth of Africa will lead its population to double by 2050, compared to 2017. This demographic problem of the African continent requires, however, linking the urban governance of African cities to sustainable development. To this end, there is no doubt that demographic planning must be included in the objectives of urban planning. It is time for the demographic transition to become an integral part of the urban planning of sustainable cities in Africa. For this to happen, a change of approach is absolutely necessary in the design and implementation of public policies in the field of urban development that are very concerned with the demographic transition.
1.3. Methodological framework
In order to carry out this reflection, we carried out an essentially documentary study combining documentary wealth and scientific rigor. The information sources were well selected and the research focused on relevant documents with identifiable sources, which were primarily made up of sustainable development strategies, national urban policies, sanitation strategies, Agenda 21, laws, monographs, journal articles, theses, etc. We searched for documents in the catalogs and databases of the University of Padua, the following web search engines and specialized portals: Google Scholar (http://scholar.google.fr/), Google Books (http://books.google.fr/), Scirus (http://www.scirus.com/), Isidore (http://www.rechercheisidore.fr/) and Theses.fr (http://www.theses.fr/). An evaluation of the quality and the relevance of the sources was necessary as well as the implementation of a documentary surveillance during the research period.
We read and analyzed urban policy and sanitation documents from several African countries. The information from these documents served as a basis for our analysis.
1.4. Prospects for changes to be implemented
Cities in African countries as a whole are struggling to meet the challenge of urbanization. Rapid population growth in African cities is not accompanied by increased and improved access to basic services. While most of Africa’s urban population resides in cities of less than 500,000 inhabitants and millionaire cities are attracting a growing share of the population, it is important to note that the phenomenon of rapid and uncontrolled urbanization is the main factor that characterizes the poor development of these cities. Innovative solutions must therefore be sought.
