UNIVERSITY OF GHANA 

 

DEPARTMENT OF GEOGRAPHY AND RESOURCE 

DEVELOPMENT 

 

UNDERSTANDING MASS WASTING IN METROPOLITAN 

ACCRA 

 

 

BY 

 

ABIGAIL AMA KUM ARHINFUL 

(10483175) 

 

 

 

THIS THESIS IS SUBMITTED TO THE UNIVERSITY OF 

GHANA, LEGON IN PARTIAL FULFILLMENT OF THE 

REQUIREMENT FOR THE AWARD OF MPHIL GEOGRAPHY 

DEGREE 

 

 

 

 

SEPTEMBER 2020 

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DECLARATION 

I, Abigail Ama Kum Arhinful, declare that this research and its entire content is a 

representation of my own work. All secondary resources have been duely 

acknowledged and I remain answerable to every question pertaining to this work. No 

part of this work has been submitted for the award of a degree in any other institution.  

 

ABIGAIL AMA KUM ARHINFUL  

INDEX NUMBER: 10483175 

SIGNATURE:  

DATE: 30th July, 2021  

 

SUPERVISORS 

 

DR. JOHN MANYIMADIN KUSIMI                   PROF. MARTIN OTENGABABIO  

(Principal Supervisor)                                              (Co – Supervisor) 

Signature:                     

Date: 30th July, 2021                                                  30th July, 2021 

 

 

  

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DEDICATION  

To my lovely family, God bless you for the support.  

 

  

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ACKNOWLEDGEMENT  

I want to first thank God almighty for life and protection. To my supervisors Dr. John 

Kusimi and Prof. Martin Oteng-Ababio, I say a very big thank you for your unflinching 

support throughout this study. Their criticisms and directives ensured the success of 

this research.  I will like to acknowledge Dr. G.A.B Yiran for his support and 

clarifications on the GIS aspect of this work. God bless you all. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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ABSTRACT 

Metropolitan areas are one the fast-growing urban metropolis in Sub-Saharan Africa 

with respect to both demographic densification and expansion of the built-up 

environment. The sprawling nature of Metropolitan Accra has also resulted in various 

human activities such as settlement, stone quarrying, and sand mining. The resultant 

effect is the exhibition of signs of mass wasting in the metropolitan area for some years 

now. Mass wasting refers to the wide variety of processes that result in the downward 

and outward movement of slope-forming materials including rock, soil, artificial fill, or 

a combination of these. The study employed a mixed-method approach to ascertain the 

triggers of mass wasting in Metropolitan Accra. Specifically, the study assessed the 

vulnerability levels, residents’ perceived risk to mass wasting and presented some 

recommendations for policy considerations. A total of 130 respondents were used for 

the study: 124 household survey and 4 in-depth interviewees. The results further 

showed that the main trigger for mass wasting as perceived by respondents in the study 

communities were anthropogenic factors with environmental impacts making majority 

of responds in relation to mass wasting.  The results again revealed that respondents at 

the summit of hills perceived themselves to be less exposed to mass wasting than those 

along the slope and base of the hill thus respondents along the slope and base of the 

slope are perceived to be at greater risk of mass wasting events. The findings again 

revealed that, majority of the communities at the northern part of Ga South were less 

prone to mass wasting compared to those of the southern part, exposed to high risk of 

mass wasting. Weija-Gbawe had some patches of areas very low to mass wasting with 

the interior part accounting for some major high-risk zones. The study suggested some 

recommendations for policy considerations to help manage the event.  

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TABLE OF CONTENTS 

 

 

DECLARATION ............................................................................................................ i 

DEDICATION ............................................................................................................... ii 

ACKNOWLEDGEMENT ........................................................................................... iii 

ABSTRACT .................................................................................................................. iv 

TABLE OF CONTENTS ............................................................................................... v 

LIST OF TABLES ........................................................................................................ ix 

LIST OF FIGURES ....................................................................................................... x 

LIST OF PLATES ........................................................................................................ xi 

CHAPTER ONE ............................................................................................................ 1 

BACKGROUND OF STUDY ....................................................................................... 1 

1.0 Introduction ...................................................................................................... 1 

1.1 Problem Statement ............................................................................................... 4 

1.2 Research Questions .............................................................................................. 8 

1.3 Research Objective ............................................................................................... 8 

1.4 Significance of Study ........................................................................................... 8 

1.5 Thesis Structure .................................................................................................... 9 

1.6 Chapter Summary ............................................................................................... 10 

CHAPTER TWO ......................................................................................................... 11 

LITERATURE REVIEW ............................................................................................ 11 

2.0 Introduction ........................................................................................................ 11 

2.1 General Overview of Mass Wasting .................................................................. 11 

2.2 Classification of Mass Wasting .......................................................................... 13 

2.2.1 Slides ............................................................................................................ 13 

2.2.2. Falls ............................................................................................................. 17 

2.2.3. Flows ........................................................................................................... 17 

2.3 Factors causing mass wasting ............................................................................. 18 

2.3.1 Climate and Water ....................................................................................... 18 

2.3.2 Geology and Soil.......................................................................................... 20 

2.3.3 Topography .................................................................................................. 21 

2.3.4 Vegetation .................................................................................................... 21 

2.3.5 Human activities .......................................................................................... 22 

2.3.6. Seismic Activities ....................................................................................... 23 

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2.4 Mass Wasting in Ghana ...................................................................................... 27 

2.5 Impacts of Mass wasting .................................................................................... 28 

2.6 Vulnerability to mass wasting ............................................................................ 32 

2.7 Risk Knowledge and Perception of Mass wasting ............................................. 33 

2.8 Mitigation and Coping Strategies ....................................................................... 36 

2.9 Remote Sensing and Geographic Information Systems in Hazard Mapping ..... 37 

2.10 Observation as a Method of Data Collection ................................................... 39 

2.11 Theoretical and Conceptual Framework .......................................................... 40 

2.11.1 Theoretical Framework: The Disaster Crunch Model ............................... 40 

2.11.2 Conceptual framework ............................................................................... 42 

2.12 Chapter Summary ............................................................................................. 48 

CHAPTER THREE ..................................................................................................... 49 

STUDY AREA AND RESEARCH METHODOLODY ............................................. 49 

3.0 Introduction ........................................................................................................ 49 

3.1 Study Area .......................................................................................................... 49 

3.1.1 Location and Size ......................................................................................... 51 

3.2 Geology and soil ................................................................................................. 52 

3.2.1 Relief and drainage ...................................................................................... 53 

3.2.2 Climate ......................................................................................................... 53 

3.2.3 Economic activities ...................................................................................... 54 

3.2.4 Population and Settlement ........................................................................... 54 

3.3 Research Methodology ....................................................................................... 56 

3.3.1 Introduction .................................................................................................. 56 

3.3.2 Philosophical Underpinning and Research Strategy .................................... 56 

3.3.3 Research Design........................................................................................... 59 

3.3.4 Data Sources ................................................................................................ 60 

3.4 Target Population ............................................................................................... 61 

3.4.1 Sample Size Determination.......................................................................... 62 

3.4.2 Sample Distribution ..................................................................................... 63 

3.4.3 Sampling Procedure ..................................................................................... 63 

3.4.4 Data Collection Methods and Tools ............................................................ 64 

3.4.5 Data Analysis ............................................................................................... 67 

3.5 Chapter Summary ............................................................................................... 75 

CHAPTER FOUR ........................................................................................................ 76 

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RESPONDENTS CHARACTERISTICS AND VULNERABILITY LEVELS ......... 76 

4.0 Introduction ........................................................................................................ 76 

4.1 The Background Characteristics of Respondents ............................................... 76 

4.2 Potential Mass Wasting Hazard Map ................................................................. 83 

4.2.1 Verification of the Mass Wasting Hazard Map ........................................... 88 

4.3 The Vulnerability levels of Respondents through Vulnerability Mapping ........ 89 

4.3.1 Mass Wasting Inventory Map of the Municipalities.................................... 90 

4.4 Relationship between Mass Wasting and the Causative factors. ....................... 93 

4.4.1 Mass Wasting and Rainfall .......................................................................... 93 

4.4.2 Mass Wasting and Land Use........................................................................ 96 

4.4.3 Mass Wasting and Soil Type ....................................................................... 97 

4.4.4 Mass Wasting and Geology ......................................................................... 98 

4.4.5 Mass Wasting and Proximity to Faults ........................................................ 99 

4.4.6 Mass Wasting and Proximity to Water Bodies .......................................... 101 

4.4.7 Mass Wasting and Proximity to Roads ...................................................... 102 

4.4.8 Mass Wasting and Slope Gradient ............................................................. 103 

4.4.9 Mass Wasting and Slope Aspect ................................................................ 105 

4.4.10 Mass Wasting and Curvature ................................................................... 106 

4.5 Chapter Summary ............................................................................................. 108 

CHAPTER FIVE ....................................................................................................... 109 

RESIDENTS’ PERCEPTIONS OF MASS WASTING ............................................ 109 

5.0 Introduction ...................................................................................................... 109 

5.1 Understanding Mass Wasting in the Ga South and Weija-Gbawe Municipality

 ................................................................................................................................ 109 

5.1.1 Types of Mass Wasting .............................................................................. 109 

5.2 Proposed level of Exposure to Mass Wasting .................................................. 115 

5.2.1 Perceived Causes of Mass Wasting ........................................................... 119 

5.2.2 Impacts of Mass Wasting ........................................................................... 125 

5.2.3 Mitigation and Coping Strategies .............................................................. 132 

5.2.4 Proposed Ways to Mitigate Mass Wasting in the Communities................ 137 

5.3 Chapter Summary ............................................................................................. 141 

 

 

 

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CHAPTER SIX .......................................................................................................... 142 

SUMMARY OF KEY FINDINGS, CONCLUSIONS AND RECOMMENDATIONS

.................................................................................................................................... 142 

6.0 Introduction ...................................................................................................... 142 

6.1 Summary of Key Findings ............................................................................... 142 

6.1.1 Vulnerability levels of Residents ............................................................... 142 

6.1.2 Residents’ Perceived Risk to Mass Wasting .............................................. 143 

6.1.3 Mitigation Practices to Mass Wasting ....................................................... 144 

6.2 Conclusion ........................................................................................................ 144 

6.3 Recommendations for Policy Consideration .................................................... 146 

6.3.1 Construction of Drainage Systems............................................................. 146 

6.3.2 Strengthening Slope Stability through Engineering Techniques ............... 146 

6.3.3 Public Education and Sensitization ............................................................ 148 

6.3.4 Re-Evaluation ............................................................................................ 148 

6.3.5 Community-based Approach to Mass Wasting Mitigation ....................... 149 

6.3.6 Sanctions .................................................................................................... 149 

REFERENCES .......................................................................................................... 150 

APPENDICES ........................................................................................................... 165 

APPENDIX A ............................................................................................................ 165 

APPENDIX B ............................................................................................................ 171 

 

 
 

  

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LIST OF TABLES 

Table 2.1:  Classification of mass wasting ................................................................... 14 

Table 2.2:  Occurrences of mass wasting events in Ghana .......................................... 16 

Table 2. 3: Some of the Deadliest Mass Movements................................................... 30 

Table 3. 1:Summary of Environmental Data Needed for Hazard Mapping ................ 61 

Table 3. 2: Table Showing a Summary of Target Population and Sample Size .......... 63 

Table 4.1: Background Characteristics of Respondents .............................................. 78 

Table 4. 2: Respondents’ Level of Education .............................................................. 79 

Table 4. 3: Respondents’ Duration and Reason for Stay in the Communities ............ 80 

Table 4. 4:  Matrix of Factor Weight Evaluation ......................................................... 84 

Table 4. 5: Number of Mass wasting Points in Each Class ......................................... 84 

Table 4. 6: Risk Level of Some Towns in the Ga South and Weija-Gbawe Municipality

 .................................................................................................................. 87 

Table 4. 7: Mass wasting Points Identified .................................................................. 91 

Table 4. 8: Mass Wasting and Rainfall ........................................................................ 94 

Table 4. 9: Mass Wasting and Land Use ..................................................................... 97 

Table 4. 10: Mass Wasting and Soil Type ................................................................... 97 

Table 4. 11: Mass Wasting and Geology ..................................................................... 99 

Table 4. 12: Mass Wasting and Distance to Fault ..................................................... 100 

Table 4. 13: Mass Wasting and Distance to Water Bodies ........................................ 102 

Table 4. 14: Mass Wasting and Distance to roads ..................................................... 103 

Table 4. 15: Mass Wasting and Slope Gradient ......................................................... 104 

Table 4. 16: Mass Wasting and Slope Aspects .......................................................... 106 

Table 4. 17: Mass Wasting and Curvature ................................................................. 107 

Table 5. 1: Perceived level of Safety in the Community ........................................... 117 

Table 5. 2: Measures Undertaken by Respondents to Cope with Mass Wasting ...... 133 

 

 

 

  

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LIST OF FIGURES 

Figure 2.1: Diagram showing the types of mass wasting ............................................ 15 

Figure 2. 2: Evidence of rock falls at Michigani, Tuba Junction ................................. 18 

Figure 2. 4: Modified Disaster Crunch Model ............................................................. 46 

Figure 3.1: Map of Ga South and Weija-Gbawe Municipal Areas .............................. 50 

Figure 3. 2: Flowchart of Methodology ....................................................................... 74 

Figure 4. 1:Location of Respondents’ Infrastructure  .................................................. 81 

Figure 4. 2: Source of Information on Mass wasting................................................... 82 

Figure 4. 3: Respondents’ Best Experience with Mass Wasting ................................. 83 

Figure 4. 4: Mass Wasting Hazard Map ...................................................................... 85 

Figure 4. 6: Mass Wasting Inventory Map .................................................................. 92 

Figure 4. 7: Rainfall and Land Use Map ...................................................................... 94 

Figure 4. 8: Monthly Rainfall Chart from 1991 to 2017 with Temperature ................ 95 

Figure 4. 9: Soil and Geology Map .............................................................................. 98 

Figure 4. 10: Distance Maps ...................................................................................... 101 

Figure 4. 11: Digital Elevation Maps ......................................................................... 105 

Figure 5.1: Success Rating Curve ................................................................................ 89 

Figure 5. 2: Proposed Level of Exposure of Mass Wasting ...................................... 116 

Figure 5. 3: Reasons for Perceived Level of Safety in the Community. ................... 118 

Figure 5. 4: Causes of Mass Wasting......................................................................... 119 

Figure 5. 5: Anthropogenic Causes of Mass Wasting in the Study Communities ..... 121 

Figure 5. 6: Natural Causes of Mass Wasting in the Study Communities ................. 124 

Figure 5. 7: Environmental Impacts of Mass Wasting .............................................. 127 

Figure 5. 8: Socio-economic Impacts of Mass Wasting ............................................ 131 

Figure 5. 9: Perceived Measures to Manage Mass Wasting ...................................... 138 

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LIST OF PLATES 

Plate 1.1: Evidence of Sand Winning around Michigani ............................................... 6 

Plate 1. 2: Picture of Deep Gully in the Ga south Municipality .................................... 6 

Plate 2.1: Mass wasting at La Conchita, California ..................................................... 31 

Plate 5.1: Evidence of Debris Slide and Debris Flow at Tuba Junction (deposited debris 

from the flow and evidence of debris slide)............................................. 111 

Plate 5.2: Evidences of Rock falls at Tuba Junction .................................................. 112 

Plate 5. 3: Evidences Debris slides and Rock Falls at Choice ................................... 114 

Plate 5. 4: Some of the New Residential Apartments at Michigani (Tuba Junction) 123 

Plate 5. 5: Some Gully Sites in the Community ........................................................ 126 

Plate 5. 6:  Retaining Walls at Tuba Junction ............................................................ 135 

Plate 5. 7: Sand bars and building elevation at Choice .............................................. 136 

Plate 5. 8: Big Gutters Chocked with Debris at around Osiadan Construction Limited

.................................................................................................................. 141 

 

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CHAPTER ONE 

BACKGROUND OF STUDY 

1.0 Introduction 

The topic of urban settlements and their exposure to damage caused by environmental 

hazards, in the past decades, has become a major research subject in both the social 

sciences and the natural sciences. Its transdisciplinary relevance comes from the fact 

that in many past scenarios catastrophic events were linked to multiple interrelated 

factors (Simon, 2019). A wide range of urban hazards such as floods, earthquakes, 

volcanic eruption and mass wasting pose a potential threat to the security of people 

living in cities and municipal areas. Over the last decades, the study of mass wasting 

processes on slopes has become a major topic of research as they are eradicating the 

successes of development (Gruber, Huggel & Pike, 2009). They occur naturally in all 

parts of the world and are part of the normal adjustments of slopes to changing 

conditions (Rodriguez, Fournier, Chamot-Rooke and  Huchon, 2012). Mass wasting 

“describes a wide variety of processes that result in the downward and outward 

movement of slope-forming materials including rock, soil, artificial fill, or a 

combination of these” (USGS, 2016). Mass wasting is a general term covering all 

natural processes by which large masses of earth material are moved by gravity from 

one place to another. The term landslide will be restricted to rapid movements in which 

soil or unconsolidated earth material moves as one or several units on a single or many 

slip planes whiles the term mass movement and mass wasting will be used 

synonymously. 

 

Mass wasting, among the various geologic hazards, are considered as one of the most 

serious geologic hazards and the third most crucial natural disaster, which threaten and 

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influence the natural and socio-economic conditions of many countries and the world 

at large (Abdallah, 2007; Igwe and Una, 2019; Schuster and Highland, 2007; Tofani, 

Segoni, Agostini, Catani, and Casagli, 2013). It is responsible for significant loss of life 

and injury to people and their livestock as well as damage to infrastructure, agricultural 

lands and housing (Perera, Jayawardana, Jayasinghe, Bandara and Alahakoon, 2018). 

Between 1990 and 2006 landslides caused more than 100,000 fatalities worldwide 

(Oven, 2005). Like other natural disasters where restoration can occur, mass wasting 

usually create permanently unstable sites that often are suitable only for designation as 

un-developable open space (Burke, Sattler and Terich, 2003). In cases where 

reconstruction is possible, solutions are often complex, expensive, and unfortunately, 

rarely work.  

 

Mass wasting is termed differently depending on factors such as material composition 

and speed of movement (Rodriguez et al., 2012). Stetler (2014) stated that, the rates of 

mass wasting processes vary from imperceptible motion to rapid translation of large 

volumes of materials buttressing van Westen, Alkema, Damen, Kerle, and Kingma 

(2011) three (3) major classifications for mass wasting. As stated by van Westen et al., 

mass wasting can be classified according to rate of movement (rapid or slow), type of 

movement (fall, sliding or flowing) and types of material involved (rock, debris or soil). 

Hazards associated with these processes are, in large part, directly a function of the 

speed of the process.  

 

The occurrence of mass movements depends largely on driving and resistant forces 

(Balsubramanian, 2011). Every mass standing on a slope possesses these forces. The 

standing mass has the driving force due to its weight. The slope and substratum have 

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the resisting force (Kusky, 2008). Slope stability depends on the equilibrium between 

the driving and restoring forces that act on potentially unstable soil mass. The driving 

forces acting on slope material, including gravity, result in a shear stress that must be 

counteracted by the available shear strength (van Beek, Cammeraat, Andreu, 

Mickovski and Dorren, 2008). In summary, when the driving forces 

(example: shear stress) overcome resisting forces (example: shear strength) the slope 

will fail thus causing mass wasting. Also, the steeper the slope’s angle, the greater the 

component of force acting parallel to the slope and the greater the chances of mass 

wasting. The steepest angle that a slope can maintain without collapsing is its angle of 

repose. It is at this angle that the shear strength of the slope’s material exactly 

counterbalances the force of gravity (Monroe and Wicander, 2006).  

 

Sahin (2004) described triggers of mass wasting as an external provocation such as 

water, earthquake and volcanic eruption that causes a near-immediate reaction in the 

form of a mass wasting by rapidly increasing the stresses or by reducing the strength of 

slope material. Weak materials such as weathered materials on slope (Geological 

causes), morphological causes by vegetation removal (by drought or forest fire) and 

tectonic uplifts as well as human disturbances like excavation of slope, loading of 

slopes (placing earth fills at the top of a slope) and artificial vibrations from explosions 

are some examples of other triggers of mass wasting (Highland and Bobrowsky, 2008).  

Mass movements often are triggered by other natural hazards. For example, mass 

wasting and flooding are closely related because both may occur due to heavy 

precipitation, runoff, and ground saturation (Mahmood, Qureshi, Tariq, Atique and 

Iqbal, 2015; Sahin, 2004). Debris flow usually occurs in small, steep channels and are 

often mistaken for floods. Mass wasting and lateral spreads often result from seismic 

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activity (Mahmood et al., 2015). Consequently, the simultaneous or sequential 

occurrence of different hazards may produce cumulative effects that differ significantly 

from those expected from a single event. This is of critical  importance in defining 

factors related to the occurrence of a given type of mass movement (Saha, Gupta and 

Arora, 2002). 

 

The incidence of mass wasting and seismicity of East Africa has been attributed to the 

existence of the East African rift valley system. In West Africa, incidence of mass 

wasting is relatively low compared to the East with incidences occurring in Cameroun 

and the Benue state in Nigeria (Midzi et al., 1991 as cited in Adu-Boahen, Dadson, and 

Yike, 2020). In Ghana however, mass wasting activities date as far back as the 1930s. 

The first incident of a mass wasting  occurred on June 15, 1933 on a section of the 

Akwapim-Togo range in the Volta region (Bokpe, 2015). In 1968, a mass wasting event 

released about 1,500 cubic meters of rock, soil and vegetation near Jamasi in the 

Sekyere District blocking the main Kumasi-Mampong truck road for a total of ten days. 

The Kasoa-Weija portions of the roads was blocked owing to mass wasting, resulting 

in a significant traffic jam for hours. The Accra-Aburi road in 2019 experienced some 

form of debris flow after a heavy down pour made it impossible for usage (Atarigiya, 

2016). These records in the country have served as a wakeup call for researchers and 

hence this study. It is therefore important that proper attention be directed to evaluating 

the full range of potential mass wasting hazards for the purposes of risk assessment.  

 

1.1 Problem Statement 

The Greater Accra Metropolitan Area (GAMA) is one of Sub-Saharan Africa's fastest-

growing urban conurbations in terms of both demographic densification and built-up 

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area (Møller-Jensen, Agergaard, Andreasen, Oteng-Ababio, and Yankson, 2020). 

According to G. S. S. (2014), the municipalities have an intercensal growth rate of  

about 3.1%. Factors such as immigration and natural population growth contributes to 

its growth and expansion. This has rendered areas that were previously neglected and 

considered unsafe (earthquake and flood prone areas, steep slopes)to be gradually taken 

over putting the populace in harm’s way  (Simon, 2019). The sprawling nature of 

Metropolitan Accra has also resulted in various human activities such as settlement, 

stone quarrying, sand mining (plate B) and the likes (Adu-Boahen et al., 2020). This 

has resulted in the cutting of the slope basement, increasing the steepness of the slope 

and the possibility of mass wasting in the area. The springing up of buildings on and 

around the hill has also increased the amount of pressure exerted on the slope and the 

removal of the vegetation cover has rendered the area susceptible and vulnerable to the 

incidence of mass wasting (Adu-Boahen et al., 2020; Alexander, 2005). Activities from 

sand winning  and  stone quarrying have left the hills with gaping holes that can collapse 

at any point in time (plate B) (News Ghana, 2015b). Seismic activities also occurs in 

Accra (Amponsah, 2004). Amponsah (2002) observed that the Weija hills area is close 

to the boundary between the Greater Accra region and the Central region, a point where 

fault lines intersect. (Adu-Boahen et al., 2020) avers that, these fault systems are an 

extension of the Romanche fracture zone, which extends from Brazil to Africa across 

the equatorial Atlantic region.  

  

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Plate 1.1: Evidence of Sand Winning around Michigani 

Source: Author’s Field Data, 2020 

 

Plate 1. 2: Picture of Deep Gully in the Ga south Municipality      

Source: Google earth 

 

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Notwithstanding the increased volume in academic literature on different aspects of 

mass wasting science such as; triggers of mass wasting (Adu-Boahen et al., 2020; 

Bradley et al., 2019; Nelson, 2013; Saemundsson, Petursson, & Decaulne, 2003), 

perception related to mass wasting (Adu-Boahen et al., 2020; Calvello, Papa, Pratschke, 

& Crescenzo, 2016; Chiu & Eidsvig, 2017; Setiawan & Hizbaron, 2014); mass wasting 

studies using GIS and Remote Sensing (Cao et al., 2019; Nugroho, 2012; Pacheco  and 

Suárez, 2014; Saha, Gupta and Arora, 2002; Sharma, 2008) mass wasting hazard 

mapping, risk assessment and management (Castro, 2013; Dahal and Dahal, 2017; 

LaPorte, 2018; Lee and Pradhan, 2007; Oven, 2005; Parkesh, 2012; UNISDR, 2016) 

and impacts and effects of mass wasting (Geertsema, Highland, & Vaugeouis, 2009; 

Gracheva & Urushadze, 2011; Kennedy, Petley, Williams, & Murray, 2015; Selby, 

2012), demonstrates a significant gap in this field of research and requires further 

investigations such as; 

a. Additional research needed to ascertain the areas more prone or not mass 

wasting in Ghana. 

b. More published academic articles on mass wasting in Ghana. 

c. Some studies of mass wasting study topics in isolation especially researches on 

hazard mapping, perception of people on mass wasting and causes and impacts 

of mass wasting  

 

This study deals with delineating the triggers of mass wasting in Metropolitan Accra, 

presenting an analysis of mass wasting based on vulnerability levels, risk perception in 

terms of experience, preparedness, causes and impacts, providing a more holistic idea 

of the occurrences of the hazard in the area. 

 

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1.2 Research Questions 

a. What are the principal causes of mass wasting in the study area?  

b. Where are the zones with the greatest mass wasting vulnerability? 

c. What are the impacts of mass wasting in the study area? 

d. How safe are the respondents in the Ga South and Weija-Gbawe Municipalities? 

e. What are some of the strategies that can be adopted to manage mass wasting? 

 

1.3 Research Objective 

The main objective of this study is to determine the triggers of mass wasting in 

Metropolitan Accra. 

Specifically, the study seeks to: 

a. Assess the vulnerability levels of residents in the study area. 

b. Determine the causes and effects of mass wasting in the study area. 

c. Gauge residents’ perception towards the risk from mass wasting. 

d. Provide recommendations for policy considerations on mass wasting. 

 

1.4 Significance of Study 

The findings of this study first will add to the knowledge of the causes and impacts of 

mass wasting along the Accra-Kasoa road. This will greatly benefit researchers 

especially those in disaster prevention and geomorphology by serving as a referral 

material. It will also help in the promotion of mitigation measures.  

 

Additionally, the findings of this study will also aid in the sensitization of stakeholders 

for improved management measures and proper urbanization measures as this will help 

in resource allocation.  It will assist stakeholders in identifying and delineating unstable 

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hazard prone areas, so that environmental regeneration programmes can be initiated, 

adopting suitable mitigation measures. It will also go a long way to help planners to 

choose favourable locations in the municipalities in when it comes to siting 

developments, townships, dams, roads and others and restrict new developments in 

hazard prone areas. further, the study will help the government in quick decision 

making for rescue and relief operations and provide researchers information on mass 

wasting.  

 

1.5 Thesis Structure 

The study is arranged in six chapters. The first chapter will introduce the study, the 

problem statement, research questions and objectives and conclude with the 

significance of the study.  

 

The second chapter reviews related literature on specific themes including mass wasting 

as a geological hazard, mass movement impact and human vulnerability, remote 

sensing and GIS in hazard mapping. The chapter will wrap up with a review on disaster 

management and vulnerability framework and adopt the Crunch “pressure and release” 

framework from (Blaikie, Cannon, Davis and Wisner, 2003)for this study.  

 

Further, the third chapter will be dedicated to the Study Area and Methodology of the 

study. Specifically, the chapter will focus on the data collection methods, sampling 

technique, sampling size, data sources and the study area.  

 

The fourth chapter analyses and discusses the vulnerability levels of respondents on 

mass wasting while chapter five looks at residents’ perceived risks of mass wasting. 

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Chapter six discusses some recommendations for policy discussions and the final 

chapter presents the summary of key findings, conclusion and recommendations. 

 

1.6 Chapter Summary 

This chapter presents the general introduction of the problem statement with some 

research questions and the objectives of the study. It also stats the significance of the 

study and the arrangement of the study. The next chapter is dedicated to the review of 

related literature, theoretical and conceptual frameworks of the study. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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CHAPTER TWO 

LITERATURE REVIEW 

2.0 Introduction 

The chapter presents literature vital to the understanding of mass wasting, a challenge 

facing most urban communities. The central theme of the chapter is the discussion of 

the classification, causes of mass wasting, its impacts and human vulnerability. The 

chapter again looks at the use of the Remote Sensing (RS) and Geographic Information 

System (GIS) techniques in mass wasting hazard assessment. 

 

2.1 General Overview of Mass Wasting 

Mass wasting according to Meinhold, Arslan, Lehnert, and Stampfli (2011) is a general 

term describing the down slope movement of sediment and rock under the pull of 

gravity without a transporting medium. It is a natural hazard that could result in severe 

damages and are difficult to control. It happens when the gravitational force acting on 

a mountain overcomes the resistive forces of that mountain which works to keep rocks 

and soil in their places. These resistive forces, including the cohesive strength and 

internal friction between materials, are referred to as the mountain slope's shear 

strength. Any factor that weakens the shear strength of the mountain slope could lead 

to mass wasting. Mass wasting generates significant financial losses as well as 

numerous fatalities and injuries. The majority of the losses occur in settlements built on 

gently sloping hillsides (Bogaard, 2001). Too often, their occurrence in places prone to 

other natural disasters, such as earthquakes, floods, or volcanic eruptions, obscures their 

full impact, resulting in unreported losses. Rapid, short-lived events, a slow-moving 

slide mass, or imperceptibly slow-moving soil creep are all examples of mass waste. 

They represent substantial short- and long-term direct and/or indirect risks. The damage 

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of structures that sustain transportation, parks and recreational places, residential and 

commercial buildings, sewage, and dam supplies are the most evident direct 

repercussions.   

 

The formation of instability in the slope system is required for the operation of mass 

movement processes. The gravitational force is the most common source of stress 

(Rudolf-Miklau, Bäk, Schmid, and Skolaut, 2011). The steepness of slopes, the 

lithological quality of slope materials, and the amount of water in the material are all 

elements that influence mass motions. The angle of friction and cohesiveness are the 

two most significant characteristics in mass movement. The gravitational force's 

magnitude is proportional to the slope's angle and the weight of slope sediments and 

rock. The equation below models this relationship. 

F = W sin Ø      …………………………………….. (1) 

Where F is gravitational force, W is the weight of the material occurring at some point 

on the slope, and Ø is the angle of the slope. 

 

The relationship between the stresses exerted to the materials that make up the slope 

and their intrinsic strength determines the slope's stability. When stresses surpass 

internal strength, mass movement occurs (Rudolf-Miklau et al., 2011). Frictional 

resistance, which is determined by the size, shape, and arrangement of the particles, 

provides intrinsic strength to slopes made of loose materials like sand and gravel (van 

Beek et al., 2008). Particle cohesion, which is governed by the availability of moisture 

in the soil, is obtained by slopes made up of silt and clay particles. Rock slopes generally 

have the greatest internal strength due to the crystalline structures (van Beek et al., 

2008).  

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2.2 Classification of Mass Wasting 

There are various classifications of mass movements dating back from the olden days 

till this present era (Abdallah, 2007, van Beek et al., 2008). The classification of mass 

wasting mostly relies on the motion and mechanism of it happening, but a more 

complex combination of processes of mass movements prevail in reality. Kusky (2008) 

argued that too much complex a classification would be ineffective. Hence three 

principal types of movement will be discussed – slide, fall and flow, and are classified 

depending on type of movement, type of material being displaced, moisture content, 

type of strain and failure and rate of movement (Abdallah, 2007; Nelson, 2018).  

 

2.2.1 Slides 

Slides can be subdivided into translational slides, which have predominantly planar 

shear surfaces, and rotational slides in which the shear plane is concave-up (Lucia, 

2014). Translational movement is common in cliff forming units, particularly where 

there are interbedded competent and incompetent rocks. It is increased by the presence 

of marls, and invariably marly or argillaceous limestones. Rotational movement 

commonly occurs in relatively unconsolidated poorly cemented sandstones, weathered 

basalts and the surficial cover. The rotational movement may result in the upper part of 

the slumped mass being back-tilted towards the failure surface (Malamund, 2014). 

There have been a number of slide occurrences around the study area and parts of 

Ghana. Slides account for the highest number of occurrences in the country (Table 2.1; 

Table 2.2; figure 2.1 a, b, c, d). 

 

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Table 2.1:  Classification of mass wasting 
Types of movement Materials in motion Moisture content Nature of movement Rate of movement 

S
li

d
e
 

Translational Rock slide Unfractured rock mass  

 

Low 

Shallow slide approximately parallel to ground surface of 

coherent rock mass along single fracture  

Very slow to 

extremely rapid 

Rock block slide Fractured rock mass Shallow slide approximately parallel to ground surface of 

fractured rock 

Moderate 

Debris/earth slide  

Rock or soil debris 

 

Low to moderate 

Shallow slide of largely deformed masses of soil Very slow to rapid 

Debris/earth block slide Shallow slide of largely undeformed masses of soil Slow 

Rotational Rock slump Rock  Low Rotational movement along concave failure plane Extremely slow to 

moderate 

Debris/earth slump Rock or soil debris Moderate Slow 

fa
ll

 

Rock fall Detached rock 

Joints blocks 

 

 

 

 

Low 

Fall of individual blocks from vertical faces Extremely rapid  

Debris/earth fall Detached cohesive 

units of soil 

Toppling of cohesive units of soil from near-vertical faces 

such as river banks  

Very rapid 

F
lo

w
 

Rock flow Rock (especially 

readily deformable 

types  such as shales 

and clays) 

Low Slow plastic deformation of rock, or soil Very slow to 

extremely slow 

Debris flow Mixture of fine and 

coarse debris (20-80% 

of particles coarser 

than sand-size) 

High Flow usually focused into pre-existing drainage lines Very rapid 

 

 

Earth flow 

Slow >80% sand-size Low Confined elongated flow Slow 

Rapid Soil containing 

sensitive clay 

Very high Rapid collapse and lateral spreading of soil following 

disturbance, often by an initial slide  

Very rapid 

Source: Adopted from Abdallah, 2007 

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Figure 2.1: Diagram showing the types of mass wasting      

Source: Abdallah, 2007 

 

 

 

 

 

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Table 2.2:  Occurrences of mass wasting events in Ghana 

Year Region Type of mass 

movement 

Corresponding number 

of mass wasting event 

Slides Falls Flows 

1933 Akwapim-Togo ranges Mass wasting 1   

1959 Saltpond bypass Mass wasting    

1960 Cape Coast  by pass   Mass wasting    

1960 Cape Coast  by pass Mass wasting    

1961 Cape Coast  by pass Mass wasting    

1961 Kumasi-   Obuasi road mile 18 Mass wasting    

1961 Kumasi-Obuasi road mile 21 Mass wasting    

1961 Kumasi- Obuasi road mile 22 Mass wasting    

1962 Sekondi college face Mass wasting    

Not known Sekondi residency face Mass wasting    

1962 Agona Akim road mile 7 Mass wasting    

1962 Agona Akim road mile 10 Mass wasting    

1962 Agona Akim road mile 9 Mass wasting    

1962 Agona Akim road mile 13 Mass wasting    

1963 Mpataba Elubu road mile 17 Mass wasting    

1963 Mpataba Elubu road mile 23 Mass wasting    

Not known Kumasi Accra road mile 5 Mass wasting    

Not known Kumasi Accra road mile 6.5 Mass wasting    

Not known Kumasi Accra road mile 3.5 

behind AGIP petrol dump 

Mass wasting    

Not known Kumasi-Mampong road mile 23 Mass wasting    

Not known Accra coast at the back of 

Ussher Fort 

Mass wasting    

Not known Accra coast near Black Star 

Square 

Mass wasting    

1969 Voltaian Scarp (near Jamasi) Mass wasting 1   

1972 Kam Mass wasting 1   

March, 2005 Kam Mass wasting 1   

June, 2010 Peduase-Water Works Road Mass wasting 1   

October, 

2010 

Adukrom-Yensi Mass wasting 1   

October, 

2012 

Wassa Essikuma & Wassa 

Nkran 

Mass wasting 1   

June, 2013 Kasoa-Weija Highway Mudslide 1   

October, 

2018 

Peduase-Ayi Mensah Road Rock fall  1  

October– 

November, 

2019 

Peduase-Ayi Mensah Stretch Mass wasting 

Rock fall 

2 1  

June, 2019 Kasoa– Accra Highway Mudslide 2   

Source: Ayetey, (1991); GhanaWeb, (2019); News Ghana, (2015a) 

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2.2.2. Falls 

Falls occur when masses of rock or other material detach from a steep slope or cliff 

and descend by free fall, rolling or bouncing (Abdallah, 2007). Falls are generally less 

frequent than slides in the study area and in the country as a whole (Table 2.1; Table 

2.2; Figure 2.1e, Figure 2.2). Falls generally occur quite suddenly with very high 

velocities. Large rock falls originating from a considerable height above the ground 

spread their debris over an extensive area unless the dispersal of material is confined 

by topography. This is very treacherous in mountainous area (Bathurst et al., 2003; 

Carere and Ratto, 2001; Fard, 2001). The highest rock fall hazard exists when joints 

and bedding planes are inclined at a steep angle, as is the case of the highly folded 

sedimentary rocks that are common in alpine mountain belts. 

 

2.2.3. Flows 

Debris and viscous flows are less related to structural discontinuity (joints, bedding 

planes) (Table 2.1; table 2.2 Figure 2.1f, g, h). High water content induces the material 

to move faster and farther from the source. A good example is a huge earth flow in 

Aaqoura area (Lebanon), where artificial lakes facilitate this flow (Abdallah, 2007). 

Although the course of debris flows is guided by channels, and to that extent is 

predictable, the speed and range of movement of these events mean that they tend to 

claim more lives than landslides (Nelson, 2018). 

 

 

 

 

 

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Figure 2. 2: Evidence of rock falls at Michigani, Tuba Junction   

Source: Google Earth 

 

2.3 Factors causing mass wasting 

The study of mass wasting involves an understanding of the factors that affect their 

occurrence. Many factors are responsible for mass wasting which can occur as a result 

of sudden or gradual changes on a slope including the types and properties of 

underlying bedrock, soils and surficial deposits, angle and direction of slope, type of 

vegetation, amount and distribution of rainfall, type of construction, placement of cuts 

and fills, and the presence of ancient mass wasting deposits. Again, certain management 

activities including clearing of forests and road construction are commonly perceived 

as potential mass wasting initiators. Some of these factors are explained below. 

 

2.3.1 Climate and Water 

Climate influences the amount and state of water in the form of snow or water. It also 

influences the type and amount of vegetation (James, Harden, and Clague, 2013). This 

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means that it “regulates” the addition or expulsion of water to increase or decrease the 

rate of slope failure and also the growth of vegetation which retards the power of 

erosion and mass wasting on a slope. Slope saturation by water is a primary cause of 

mass wasting. Saturation can occur in the form of intense rainfall, snowmelt, changes 

in ground-water levels, and surface water level variations along coastlines, earth dams, 

and in the banks of lakes, reservoirs, canals, and rivers (Guzzetti, Peruccacci, Rossi, 

and Stark, 2005; James et al., 2013).  A study by Oven (2005) and Alexander (2005) 

revealed that, the predominant trigger of mass wasting activity was highly intensified 

and prolonged rainfall, with earthquakes and volcanoes being the far less frequent 

triggers.  

 

Highland and Bobrowsky (2008) also stated that mass wasting and flooding are closely 

allied because both are related to precipitation, runoff, and the saturation of ground by 

water. Mass wasting can cause flooding by forming mass wasting dams that block 

valleys and stream channels, allowing large amounts of water to back up. This causes 

backwater flooding and, if the dam fails, subsequent downstream flooding. Alam 

(2020) also concluded that heavy rainfalls are the main cause of mass wasting in 

Rangamati and Chittagong which are communities in Southeast Bangladesh. According 

to Alcantara-Ayala and Moreno (2016), rainfall was documented as the main trigger of 

mass wasting in recent decades but the respondents also considered earthquake since 

seismic activity is common on a regional level.  Igwe and Una (2019) added in their 

studies at Nanka, Nigeria that mass wasting in the area is mainly during the rainy 

season, and are triggered by water infiltration in slopes with high gradient, where poorly 

consolidated sands overlies less permeable silty clay units in the Nanka Formation. The 

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increase in pore water pressure due to soil saturation leads to the reduction of the shear 

strength and loss of apparent cohesion. 

 

Sahin (2004) studied the relationship between the amount of rainfall and frequency of 

mass wasting events and also established that increase an in the number of mass wasting 

coincided with the period of increased rainfall. Guzzetti et al. (2005) reported that the 

degrees of severity of Himalayan mass wasting are increasing due to heavy or 

prolonged rainfalls, earthquakes, or both. It was reported that the majority of the mass 

wasting occurred when daily rainfall was higher than 200 mm. 

 

2.3.2 Geology and Soil 

Geological characteristics are one of the most crucial controlling factors of mass 

wasting, since each geological unit have different susceptibility rates. Weak rocks like 

sedimentary rocks will weather quickly than hard rocks like igneous and metamorphic 

rocks (Ameer et al., 2008).  

 

Abdallah (2007) articulated that, mass wasting is quite important in areas where clayey 

rocks (clay-stones, marls, shales, muds, flysch) or morainic materials outcrop. Thus, 

higher soil clay percentage generally increases mass wasting susceptibility. This is 

because the presence of clay minerals between soil mineral particles can cause mutual 

repulsion force which causes friction between mass wasting causing particles especially 

when saturated with water.  Yalcin (2007) in a study established that mass wasting 

mostly occurs on clay soils. The author further added that, higher clay fraction is more 

susceptible for landslides due to its extreme expansion potential. Guzzetti et al. (2005) 

further stated that, increase in soil moisture (especially soils with high clay contents) 

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due to rainfall reduces the cohesion of the soil particles. The excess moisture present in 

soils exerts pore water pressure making steep slopes vulnerable to landslides, under 

adverse climatic conditions. 

 

2.3.3 Topography 

The steeper the slope, the more likely it is to fail and the easier it is to upset equilibrium. 

Most mass movement occur along slopes that are 20° or 25° steep (Cardinali et al., 

2002; Carrara et al., 2003). In addition, slope aspect is strongly affected by the 

microclimate and vegetation cover, thus influencing soil development and mass 

movement intensity. ‘Slope aspect defines the direction of slopes and reveals potential 

effects of prevailing winds, other weather conditions and incident solar radiation. The 

orientations by virtue of the local conditions receive more quantity or intense rainfall, 

the soil gets saturated more quickly, depending moreover on infiltration capacity, 

controlled by slope angle, soil type (permeability and porosity) and vegetation cover’ 

(Psomiadis et al., 2020 pg 10). High roughness slopes are more prone to mass wasting 

because gradient changes favour rainfall infiltration into the soil (Fard, 2001). 

 

2.3.4 Vegetation 

‘Vegetation and slope stability are interrelated by the ability of the plant life growing 

on slopes to both promote and hinder the stability of the slope. The relationship is a 

complex combination of the type of soil, the rainfall regime, the plant species present, 

the slope aspect, and the steepness of the slope’ (Food and Agriculture Organisation of 

the United Nations, 2007). Vegetation limits the movement of the debris present along 

slopes in two folds, that is, hydrological (capacity of infiltration into the soils, soil 

moisture, groundwater level and others), and mechanical (root length) (van Beek et al., 

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https://en.wikipedia.org/wiki/Plant
https://en.wikipedia.org/wiki/Slope_stability
https://en.wikipedia.org/wiki/Soil
https://en.wikipedia.org/wiki/Climate
https://en.wikipedia.org/wiki/Aspect_(geography)


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2008). Through reinforcement, roots mechanically reinforce a soil transfer of shear 

stresses in the soil to tensile resistance in the roots, soil moisture modification via 

transpiration and interception. The foliage limit build-up of soil stress, destabilizing the 

influence from turning moments exerted on a slope as a result of strong winds blowing 

downslope through tress (wind throwing). Lastly, through buttressing and arching, 

anchored stems can act as buttress piles along a slope counteracting shear stresses 

(Bornsworth, 2015; Nelson, 2018; van Beek et al., 2008). The major effect of 

transpiration is the reduction of soil pore water pressures which counteracts the loss of 

strength which occurs through wetting, this is most readily seen as a loss of moisture 

around trees (van Beek et al., 2008). Greenwood, Norris, and Wint (2004) however 

argued that, it is not easy to rely on tree and shrub roots to remove water from slopes 

and consequently help ensure slope stability but it can be assumed that the chance of 

slope failure following saturation by storm event or periods of extended rainfall will be 

lessened as a result of transpiration. 

 

Alternatively, vegetation can increase the hazard by overloading the slope with weight 

and by weakening the regolith strength through movement of the roots, for example 

during strong wind storms (Popescu, 2002; Reinhold, Medicus, Wolfgang and Zangerl, 

2009). Another observed effect is that the vegetation cover indeed stabilizes the slope 

through root reinforcement; however, if the slope fails, the root weight could actually 

increase the size of the mass wasting (Papathoma-Koehle and Glade, 2013). 

 

2.3.5 Human activities  

As the population on earth continues to increase, more land is colonized. Therefore, 

previously rejected areas are being occupied. Land-use activities affect the intensity of 

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mass movement significantly (Pullanikkatil, Palamuleni and Ruhiiga, 2016). Clearance 

of forest or erecting terraces for agriculture, tillage of the top soil, rock fragment 

removal from top soil, abandonment and regeneration of land, uncontrolled burning, 

and overgrazing are among the main human activities on landscapes (Kerényi, 2010; 

Siddhartho, 2013). These activities are constantly reshaping the contours of the land 

(topography) and thus altering the natural slope. In some instances, they can be 

considered as the primary cause of mass movements. As an example, unregulated 

mining operations have turned stable terrain (limestone) into mass wasting-prone 

terrain (Deniz et al., 2018). Residential development not only adds weight to the slope 

but may also lubricate fractures due to garden watering, and the seepage of water from 

swimming pools and sewage effluent systems (Goldewijk, Beusen, Drecht and Vos, 

2011). In addition, vibration of trucks, machinery, blasting, fluctuating groundwater 

level (well drilling and over-pumping), and loss of root binding can constitute important 

transitory stresses that may lead to failure (Goldewijk et al., 2011). 

 

2.3.6. Seismic Activities 

In places where minor and significant morphotectonic processes (uplift, subsidence, 

faulting, jointing, and earthquakes) occur, mass movements are common (Ahulu et al., 

2018). Aside from the immediate effects of material collapse that is already 

precariously stable, earthquakes can exacerbate other types of instability by lowering 

rock shear resistance. In literature, some examples of strong relationships between 

seismic occurrences and mass movements have been described. In 551 A.D., a large 

earthquake that struck Lebanon depicts massive slides at Chekka, which is responsible 

for forming the city's current coastal structure, mass wasting induced by the Kashmir 

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earthquake in October 2005 (Mahmood et al., 2015), earthquake-driven Peru valley 

mass wasting in 2018 (Bradley et al, 2019), and many others. 

 

Ghana is situated on the south-eastern edge of the West African Craton, far from any 

active plate borders (Amponsah, Leydecker and Muff, 2012). Since 1615, when an 

earthquake was discovered near Elmina on the Cape Coast, it has been prone to 

devastating earthquakes. (Ahulu et al., 2018). Earthquakes in Ghana are concentrated 

in the south (Figure 2.2), where a network of seismic recording stations has been 

established. Most of the epicenters south of Weija, according to Amponsah (2004) are 

owing to the existence of an ancient thrust zone that has been reactivated. Recent mass 

wasting activities in these locations, as well as seismic events, provides reason to be 

concerned. The majority of earthquakes in Ghana occur in the western area of Accra, 

near the intersection of two major fault systems, the Coastal boundary fault and the 

Akwapim fault zone, according to the report. 

 

2.3.6.1 Seismotectonics in Ghana 

Ghana lies between two major fault lines: Akwapim Fault and the Coastal Boundary 

fault. 

 

2.3.6.1.1 Akwapim Fault 

The Coastal Boundary Fault Zone and the Akwapim Fault Zone are the two major 

active fault zones in Ghana where the majority of recent earthquakes or tremors have 

occurred (Fig. 2.2). The Akwapim fault, which runs northeast from Accra, is part of the 

Akwapim fault zone, which has seen more recent faulting along an ancient line of thrust 

boundaries between the Birimian at the west end of the Togo Series and the Dahomeyan 

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at the east end of the Togo Series. A range of medium-grade metamorphic rock units 

make up the Dahomeyan (GSD and BGR, 2009). The Akwapim fault zone runs 

northeast through Kpong, Ho, and into Togo and Benin (Fig. 2.2). Recent large-scale 

mapping in the southern part of the Akwapim fault zone (Muff and Efa, 2006 , quoted 

by Ahulu et al., 2018) demonstrates that the Akwapim–Togo Belt was subjected to a 

block tectonic style of deformation at a later period, and that several local-scale normal 

faults have evolved recently (Fig. 2.3) 

 

2.3.6.1.2 Coastal Boundary fault  

During the Atlantic Ocean's opening, the West African continental margin formed 

(Amponsah, 2004). The early era of opening was linked to basic magmatism. From the 

Jurassic to the present, flanking sedimentary troughs developed around the continental 

border, with subsidence ongoing. The sediment troughs are defined by faults that 

separate various crustal blocks and have remained active throughout the history of 

subsidence, with the Coastal Boundary Fault being the most active. At a distance of 3–

5 km from the coast, it strikes approximately north 60°–70° east and down throws the 

block south of it for several kilometres (Ahulu et al., 2018). 

 

 

 

 

 

 

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Figure 2. 3: Tectonic setting of the southern portion of Ghana          

Source: Ahulu et al., 2018 

 

The Coastal Boundary Fault runs along the northern edge of a basin filled with Upper 

Jurassic to recent deposits. The Coastal Boundary Fault, according to Amponsah 

(2004), forms the northern edge of the Keta Basin and supports the claim that the flaw 

might be active during the entire deposition process. The fault curves to the west of 

Accra, striking east-west, and intersects with the Nyanyanu fault in the Akwapim fault 

zone. Earthquakes have occurred in the past and are still expected to occur around the 

intersection of the Akwapim fault zone and the Coastal Boundary fault zone, according 

to a recent study of geological and instrumental recordings (Amponsah, 2004; Kutu et 

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al., 2013). There are a number of other faults in the acute angle between these two major 

faults, the most important of which is the Weija fault striking West North West (Fig. 

2.2). Numerous active faults have been mapped during the course of foundation 

investigation studies in and around Accra. The area within the acute intersection has 

high seismicity. Plate tectonic forces, according to (Amponsah, 2002), are responsible 

for tectonic activity in West Africa and proposed that the African plate's northward 

movement over the Earth's ellipsoid-shaped surface creates extensional stresses, which 

are still present today. These extensional forces were thought to be contributing to 

seismic activity in the West Africa zone, and as a result, some faults within the zone 

could become active.  

 

2.4 Mass Wasting in Ghana 

Ghana is not noted to be a frequent serious victim of mass movement. It is, however, 

noteworthy that Ghana has not been without mass wasting (Atarigiya, 2016). Mass 

wasting are generally of small scale although they affect highways and some opencast 

mines. Major mass wasting have occurred along the entire length of the receding 

Voltarian scarp.  Modes of mass wasting have been studied in different geological and 

climatic-vegetational zones of the country (Atarigiya, 2016). It has become obvious 

that Ghana's slope instability problem may be divided into two categories: slope 

instability that can be controlled via good design and slope instability that cannot be 

controlled or corrected and should therefore be avoided. Mass wasting occurs in many 

parts of the country, especially in the central and southern parts (Sambou, 2019). Table 

2.2 (pg 17) shows the number of occurrences in the country.  

 

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2.5 Impacts of Mass wasting 

The motivation behind mass movement studies is the prevention and mitigation of 

disasters and reduction of risk. Most mass wasting events are small and their killing 

potential is limited. However, large mass wasting events may be very catastrophic. 

Delayed consequences to mass wasting may also tragically contribute to the death toll 

(Vittorio de Blasio, 2011).  The negative consequences of mass movements however 

are not limited to loss of life, but include the destruction of houses and infrastructure, 

loss of productivity in the area affected, unpredictable changes in the local watercourse, 

and reduction of arable or habitable land (Department of Geological and Geophysical 

Surveys, 2019).  In 1786, a local river in the province of Sichuan in China was dammed 

for 10 days as a result of a mass wasting event caused by a strong earthquake. As many 

as 100,000 people were drowned when the dam failed inundating 1,400 km area 

downstream. In 2005, a major landslide killed about 10 people and destroyed dozens of 

houses in the town of La Conchita, California (Plate C). The event happened at the end 

of a 15 – day rainfall.  At Abancacy, Peru, a mass wasting event occurred on January 

27, 2019 that killed at least 15 people and injured 34 when it destroyed part of a hotel 

during a wedding celebration (Plate D). Also, on December 4, 2019, heavy rains 

precipitated the deadly series of Burundi with mass wasting following later that night 

into the next day, affecting over 500 people in Nyempudu, Gikomero and Rukombe of 

the North-western province of Cibitoke bordering Rwanda and Bubanza as well as the 

North-western province of Cankuzo. This event killed at least 26 people, leaving 10 

missing and injuring 10 others. Much property damage occurred as well. Table 2.3 

reports some of the deadliest mass wasting on the Accra-Kasoa highway. In 2013 and 

2019, heavy rains in Ghana caused mudslides where silt and muddy pools of water 

covered most parts of the road few kilometres from the Kasoa tollbooth making it 

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extremely difficult for drivers to use the road. In the absence of proper drainage in the 

settlements, running water and mud from the hills create deep gullies and ends up on 

the road (ABC News, 2019; Acquah, 2019). Sand from these hills also ends up in the 

Weija dam, swelling up its volume which floods other low-lying communities such as 

Denchira, Salami Kope, Ghanant farms, Gape Kope, Daniel Kope, Torgah Kope, 

Kwame Zolo Kope, Sackeyman, Ayigbe Kope, etc around the dam (Boakye, 2015).  

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Table 2. 3: Some of the Deadliest Mass Movements 
Location Country  Date Number of people 

Killed 

Mass Movement Type and Notes 

Italy Austria 1916 10,000 Mass wasting 

Gansu Province China December 16, 1920 180,000 675 loess flows affected an area  

of 50, 000km2 

China  1920 200,000 Earthquake triggered mass wasting 

Japan  1945 1,200 Flood triggered mass wasting 

USSR  1949 12,000-20,000 Earthquake triggered mass wasting 

Yungay (Nevado Huascaran) Peru May 31, 1970 18,000 Rock avalanche mixed with ice and water, caused by 

earthquake along the path of the glacier 

Armero (Nevado del Ruiz) Columbia November 13, 1985 25,000 Lahars formed by eruptions of ice-capped Nevado del Ruiz 

volcano 

Khait Tajikistan 1949 12,000 Rock avalanche detached by strong quake 

Austria  1954 200 Mass wasting 

Huaraz Peru December, 1941 4,000-6,000 Debris flow caused by morain dam break impounding glacial 

lake (GLOF); more events in 1962 and 1970 

Kelud Volcano Indonesia 1919 5,160 Drainage of the Crater lake  

Yungay (Nevado Huascaran) Peru January 10, 1962 4,000-5,000 Rock avalanche mixed with ice and water, caused by 

earthquake 

Colima Honduras September 20, 1973 2,800 Rock avalanche mixed with ice and water, caused by 

earthquake, and debris flow Ranrahirca (Nevado 

Huascaran) 

Peru January 10, 1962 4,000 

Longarone (Belluno) Italy October 9, 1963 2,000 Rock avalanche onto artificial water reservoir, killing due to 

water splash 

Bihar, Bengal India October 1, 1968 1,000 The region is prone to large quakes  

Villa Tina (Medellin) Columbia September 27, 1987 217 Small and shallow slide in lateritic residual soils 

Ecuador  1987 1,000 Earthquake related mass wasting 

El Salvador  2001 585 Earth quake induced mass wasting 

La Conchita California 

(USA)  

January 10, 2005 10 Debris flow mobilized previous mass wasting deposits due to 

intense rainfall 

Philippines  2006 1126 Rain triggered Avalanche killing lots of people 

Taiwan  2009 600 Typhoon Marakot triggered avalanche 

Gansu China 2010 1287 Rain triggered mudflow 

Northern India  2013 5700 Heavy rain triggered mass wasting 

Sierra Leone  2017 >1140 Mudflows 

Source: Adapted from Malamund, 2014; Nelson, 2018; Vittorio de Blasio, 2011 

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Plate 2.1: Mass wasting at La Conchita, California                   

Source: USGS, 2016 

 

 
Plate 2.2: Mass wasting at Peru at a Hotel Causing the Walls of the Hotel to 

Collapse during a Wedding Ceremony.                          

Source: USGS, 2016 

 

 “Mass movements are destructive agents. They change and modify the landscape – 

they disturb it. Destruction and disturbance is costly for built environment, it is costly 

for natural resources and yet it is essential for ecosystem cycling in the natural 

environment” (Geertsema, Highland, & Vaugeouis, 2009 p. 589).  

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2.6 Vulnerability to mass wasting  

The term vulnerability as has been applied in many fields today has spanned a very 

long period of time. Weichselgartner (2001) regarded vulnerability as a fuzzy and stated 

that the term has no common conceptualization. UNISDR (2016 pg. 1) defined that 

vulnerability “is the conditions determined by physical, social, economic and 

environmental factors or processes, which increase the susceptibility of a community 

to the impact of hazards”. Proag (2014 pg. 370) added that it is “the degree to which a 

system, or part of a system, may react adversely during the occurrence of a hazardous 

event. Thus, people become “vulnerable” if access to resources either at household, or 

at an individual level is the most critical factor in achieving a secure livelihood or 

recovering effectively from a disaster”.  

 

To understand the concept of vulnerability, Weichselgartner (2001) identified 3 

distinct themes within vulnerability discourse. The first theme examines vulnerability 

in the context of pre-existing conditions. These conditions refer to human occupancy 

of zones or regions termed as hazardous such as earthquake, flood prone areas and 

seismic zones. In the context, of this study identifying persons living in mass wasting 

prone areas, what the author failed to add were determining residents’ knowledge and 

their perception of risk and exposure with regards to the hazard in question as well as 

the levels of vulnerability of the area. The second group focuses on the coping responses 

including societal resistance to hazards. Finally, vulnerability is considered hazard 

place specific which combines the earlier two themes. This third theme was noted as 

geographically oriented. Vulnerability in this regard is considered as a bio-physical risk 

and social response that is examined at a specific area or geographical region. Various 

theoretical perspectives have also been advanced to explain the causes of vulnerability. 

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From a social vulnerability viewpoint, Watts and Bohle (1993) noted 3 processes that 

define vulnerability. They include economic capabilities (entitlement), empowerment 

(political/social power) and the political economy (historical/structural) (cited in) 

(Weichselgartner, 2001). Another model popularly referred to as the pressure and 

release model or the disaster crunch model was proposed by Blaikie et al. (1994). This 

model integrates much more elements under a cause and effect relationship between the 

elements that constitute vulnerability. According to Blaikie et al. (1994), the model 

includes in it “unsafe conditions that expose one to social vulnerability when in contact 

with any type of hazard”. The model also highlights “dynamic pressures” as another 

element. Much focus is oriented to this element as it explains the underlying driving 

forces that make a system vulnerable. 

 

2.7 Risk Knowledge and Perception of Mass wasting 

People’s feelings according to Lowenstein et al., (2001) and Slovic et al., (2002)  about 

what is good or bad in terms of causes and consequences of risks shape their beliefs 

about risk. Slovic (2000) further added that how people perceive and respond to risk is 

a function of their knowledge, experience, values, attitudes and feelings about the 

seriousness and acceptability of risks. When it comes to developing systems, 

procedures, and policies to safeguard local populations, risk perceptions are crucial. It 

is a series of psychological processes that occur when engaging with and/or 

comprehending a natural or built-environment hazard (Chauvin et al., 2007). It also 

demonstrates how communities, governments, and people perceive, judge, evaluate, 

and rank risk. Direct observation (that is, being present at a mass wasting) or knowledge 

gathered from other people, media, or social networks may be the source of these 

processes (for example, to read about an earthquake). Individuals or groups differ in 

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their perception of psychological, cultural and social factors (Calvello et al., 2015). That 

is to say, people take risk-related decisions from a range of alternatives based on local 

knowledge, past experience, experiments, opportunities and existing coping 

mechanisms. While outsiders might label two households as equally vulnerable – 

because they live in apparent similar conditions – the two households might still 

perceive risk differently and, as a consequence, prefer different risk reduction measures. 

The degree of perceived risk varies greatly among households and depends on class, 

gender, location, and other particular conditions shaped by economic, social and 

political processes (Heijmans, 2001). 

 

Reality is constructed from perception in order to give the world more meaning and to 

respond to that meaning. When people have more disaster experience, that experience 

impacts their perceptions more, and when there is a lack of experience or the crisis is 

thought remote, judgments are more likely to be based on information gained through 

the media, as well as their own intuition (Alcantara-Ayala and Moreno, 2016) and 

immediate social networks.  

 

Decision makers need to understand how people think about and respond to risks 

(Chauvin et al., 2007). This understanding helps improve risk communication among 

lay people. Not only technological, engineering and scientific aspects of risks have to 

be considered, but also the public concerns about the acceptable level of these risks 

needs to be evaluated. Public risk perceptions can fundamentally compel or constrain 

political, economic and social action to address particular risks (Leiserowitz, 2006).  

 

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A study by Chaturvedi and Varun (2015) on the public perceptions of mass wasting risk 

in the Himalayan Mandi Town revealed that since catastrophic mass  wasting are rare 

events, most of the people of the town were risk averse. They did not show prevention 

behaviour, and they were not well prepared for an adverse event. Again, most of the 

respondents were of the belief that they lived in a safe place. This reiterated a previous 

study by Winter & Bromhead (2012) that indicated that most of the respondents showed 

low level of concern with mass wasting, indicating that though they know mass wasting 

is a problem, they are not especially worried about it. Further, they indicated that the 

most frequent source of information for mass wasting was the media followed by 

official and geotechnical reports then their personal experience. Qasim et al. (2018) 

added a little twist to it by studying the socio-economic determinants of mass wasting 

risk perception in the Muree hills of Pakistan. Age, income, educational levels, location 

and experiences were listed as variables that affect mass wasting risk. The results 

revealed that out of the five, three of them including past experiences, location and 

educational level were found to have positive effects on mass wasting risk perception. 

The findings also revealed that past experience is a good predictor for risk perceptions 

of natural hazards but a similar computation by Setiawan and Hizbaron (2014) revealed 

that there is no correlation at all between these variables and mass wasting experience 

but on the other hand these, these variables have a relationship with the respondents 

perception of mass  wasting.  

 

Some studies have found a weak or insignificant link between risk perception and 

disaster preparedness (Lindell and Whitney, 2000; Siegrist and Gutscher, 2006), while 

others have found a link between higher levels of perceived risk and increased 

preparedness behavior (Martin, Martin, and Kent, 2009; McNeil, Dunlop, Heath, and 

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Morrison, 2013; Miceli, Sotgiu, and Settanni, 2008; Paul and Bhuiyan, 2010). The 

perceived threat severity was favorably connected with disaster preparedness, 

according to McNeil et al. (2013), however the relationship between perceived threat 

likelihood and disaster preparedness was not as strong. 

 

2.8 Mitigation and Coping Strategies 

Hazards have always been a part of life, and residents of hazard-prone locations have 

developed techniques to deal with extreme events based on their own capacities, skills, 

talents, knowledge, and technologies. These adaption tactics, which they learned from 

their forefathers and their own experiences, have become part of their traditions and 

culture (Heijmans, 2001; Weichselgartner, 2001). When disasters hit, people have 

always been prepared to cope and have not relied heavily on outside help and assistance, 

such as from the government. These strategies can be considered as mitigation and 

coping strategies. 

 

Coping strategies refer to the application of indigenous knowledge in the face of 

hazards (Setiawan and Hizbaron, 2014). Mitigation and coping strategies are put in 

place to reduce the impacts and risks of hazards through proactive measures taken 

before an emergency or disaster occurs. According to  Westen and Kigma (2011), fair 

knowledge on mitigation coping strategies is important to ascertain the type of disaster 

risk reduction programme that should be undertaken.  

 

A research by  Chaturvedi and Varun (2015) on the public perceptions of mass wasting 

risk in the Himalayan Mandi Town revealed that to reduce mass wasting risk, majority 

of the responded vouched for planting of trees followed by building stronger 

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foundations for their buildings. Osuret et al. (2016) agreed with the results but further 

added that from his findings terracing was a better coping strategy for reducing the risk 

and effects of mass wasting. They added that majority of the respondents relied on the 

support of government to help them cope. The research grouped coping strategies into 

economic, technological and social. Economic coping strategies included strengthening 

financial institutions; social coping strategies included night patrols and meetings to 

assist people affected by mass wasting whiles technological strategies looked at 

improving public facilities such as roads and water channels.  

 

2.9 Remote Sensing and Geographic Information Systems in Hazard Mapping 

Mass wasting hazard mapping is a fundamental tool for disaster management activities 

in fragile mountainous terrains (Dahal and Dahal, 2017). The basis for hazard maps is 

a comprehensive assessment of geological and hydro(geo)logical framework 

conditions, slope instabilities, relevant triggering mechanisms, properties of 

displacement processes, potential risks and the vulnerability of endangered areas 

(objects) (Rudolf-Miklau et al., 2011).  

 

Extraction of significant spatial information related to mass wasting occurrence is an 

integral part of hazard assessment. RS data married with GIS have proven to be 

competent tools for generating and processing spatial information. The advancement in 

earth Observation (EO) techniques facilitate effective mass wasting detection, 

mapping, monitoring and hazard analysis ( Tofani, Segoni, Agostini, Catani, and 

Casagli, 2013).  

 

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Aerial photographs are widely used for mass wasting detection and mapping using RS 

(Pardeshi, Autade, and Pardeshi, 2013). For accurate mass wasting detection and 

mapping, good quality aerial photographs are needed but they cannot be used in 

continuous mass wasting monitoring since it does not prove repetitive coverage of the 

same area (Sharma, 2008). In assessing the risk of mass waste, the Digital Elevation 

Model (DEM) is critical. Slope angle, slope aspect, curvature, lineaments, drainage, 

ridges, and other theme data layers can be retrieved with good resolution from DEM. 

Thematic data layers, computation of different indices, weight assignment, data 

integration, and the development of mass wasting susceptibility and hazard maps are 

all common uses of GIS in mass wasting hazard assessment. Several GIS-based mass 

wasting susceptibility zonation approaches exist, including the Artificial Neural 

Network (ANN), Decision Tree model, Weighted Overlay, and physically based mass 

wasting hazard models.(Abdallah, 2007; Pullanikkatil, Palamuleni, and Ruhiiga, 2016). 

 

Pareta and Pareta (2012) used GIS and remote sensing techniques for mass wasting 

susceptibility mapping together with the weighted overlay method (WOM) to map the 

Giri river watershed of Yamuna basin. The study made use of data layers such as land 

use, vegetation cover, geology, slope gradient, aspect, drainage density and terrain 

height. The study concluded that, coupled with remote sensing, GIS is an excellent tool 

to display the spatial distribution of mass wasting along with their attributes. Rodeano 

et al., (2017) in their studies which also used WOM for mass wasting susceptibility 

analysis agreed with this and further stated that RS and GIS for hazard mapping helps 

planners in general planning assessment purposes. The study used the probabilistic 

method to obtain the weights of soil, geomorphology, distance to river, distance to 

lineaments, land use and lithology. Othman et al., (2012) in their research further added 

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multi-criteria decision making together with GIS is a powerful tool, which can be 

applied to predict and map mass wasting hazard zones. 

 

2.10 Observation as a Method of Data Collection  

Observation is a method gathers data by watching behaviour, events, or noting physical 

characteristics in their natural setting without questioning or otherwise communicating 

with them (Centre for Disease Control And Prevention, 2018). This method is adopted 

by researchers to attempt to understand behaviour, societies and phenomenon by getting 

to know the persons and events involved, their symbols, beliefs and emotions. The 

technique qualifies as a scientific method of data collection when it is specially 

designed to answer a research question and it is systematically planned and executed 

with proper controls (Centre for Disease Control And Prevention, 2018). The versatility 

of the method makes it an indispensable primary source of data and a supplement to 

other methods. Observation can be structured or unstructured. Structured observation 

is where data is collected using specific variables and according to a pre-defined 

schedule while unstructured observation is a free and open manner method of data 

collection such that there will be no pre-determined variables or objectives (Whittle, 

Giazitzoglu, Wright, and Casey, 2019).  According to Dudoviskiy (2014), some 

advantages of this method include high flexibility in terms of application, direct access 

to research phenomena and the generation of a permanent record for future referrals. 

Data can be collected in real-time while the phenomenon occurs or in suspended time 

by recording an event and later analysis via videos, field notes and photographs (Whittle 

et al., 2019). 

 

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2.11 Theoretical and Conceptual Framework 

The theoretical and conceptual framework of a study explains the path of a research 

(Dickson et al., 2018). It must be noted that, the overall aim of this is to make research 

findings more meaningful, acceptable to the theoretical constructs in the research field 

and ensures generalizability. In addition, it assist in stimulating research while ensuring 

the extension of knowledge by providing both direction and impetus to the research 

inquiry. The frameworks further enhance empiricism and rigor of a research. It is thus 

no exaggeration for Imenda (2014) to say that both the theoretical and conceptual 

frameworks give life to a research. 

 

2.11.1 Theoretical Framework: The Disaster Crunch Model 

Dickson et al. (2018) accentuate that theoretical frameworks are the specific theories 

about aspects of human endeavour that can be useful to the study of events. The 

theoretical framework consists of theoretical principles, constructs, concepts, and 

tenants of a theory (Grant and Osanloo, 2014). Imenda (2014) acceded to the fact that 

theoretical framework assist researchers in situating and contextualizing formal 

theories into their studies as a guide. This positions their studies in scholarly and 

academic fashion. Moreover, the theoretical framework serves as the focus for the 

research and it is linked to the research problem under study. Therefore, it guides a 

researcher’s choice of research design and data analysis plan.  

 

There are lots of disaster models which include the Traditional or Disaster Management 

Continuum, the Kimberly, the Expand-contract and the Crunch model. The study 

adopts the disaster crunch model as the theoretical framework to explain its findings. 

The Disaster Crunch Model states that, a disaster happens only when a hazard meets a 

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vulnerability (Hai and Smyth, 2012). People can be said to be vulnerable when they are 

unable to adequately anticipate, withstand and recover from a hazard. The model has 

two main dimensions: hazards and vulnerability, both of which influence the disaster 

risk (Fussel, 2007). The level of disaster risk therefore depends on the magnitude of the 

hazard and degree of vulnerability of the people. As explained above, a disaster will 

not happen if there is only hazard without a vulnerable community and vice versa.  The 

Crunch model has been viewed as a framework of understanding and analysing the 

causes of disasters (Heijmans, 2001). The behaviour and trends of a hazard can be 

understood through examining its force, any warning signs, forewarning, speed of 

onset, frequency, time of occurrence and duration. Climate, or weather related hazards, 

should also be considered and analysed in the context of a changing climate, as the 

frequency, intensity and seasonality of climate related hazards, such as typhoons, floods 

and droughts may be affected (Dickson et al., 2018). Three layers of social processes 

that cause vulnerability are; root causes, dynamic pressures and unsafe conditions. The 

root causes (example: lack of government policy on land use planning) lead to dynamic 

pressures (example: no community organisation for collective efforts to reduce mass 

wasting) that explain how the unsafe conditions (example: poor housing conditions, 

dangerous location) have arisen and persisted (Heijmans, 2001).  

 

According to Wisner et al, (2003), the crunch model (Figure 2.4) adopts a cause and 

effect perspective because of its focus on the causes and impact of disaster. The model 

is also known to analyse vulnerabilities and coping capacities of disaster affected 

communities. According to the crunch model (Figure. 2.4), the progression of 

vulnerability of a community is revealed. Furthermore, the underlying causes that fail 

to satisfy the demands of the people are identified (Asghar et al., 2006). This model 

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goes further to estimate the dynamic pressures and unsafe conditions (Figure 2.4). The 

model is important as it can help practitioners to understand and react to people’s 

vulnerability to disasters (Hai and Smyth 2012). It therefore explains the relationship 

between natural hazards and vulnerabilities of communities, making the model 

applicable in this study. Hai and Smyth (2012) assert that the crunch model helps 

practitioners to understand and react to disaster vulnerabilities facing people. (Blaikie 

et al., 2003) notes that pressure can be released on those communities vulnerable to risk 

by decreasing or eliminating the various root causes, dynamic forces, and/or unsafe 

conditions available. It is for these reasons that the model was adopted for this study. 

However, the disaster crunch model has also not been spared from criticism of scholars 

and practitioners. Turner II et al. (2003) have argued that the crunch model lacks the 

feedback in the system. Cutter et al. (2008) noted that the model tracks the progression 

of vulnerability from the root causes, through to dynamic pressures, and to unsafe 

conditions, but fails to adequately address the coupled human–environment system 

associated with the proximity hazards. 

 

2.11.2 Conceptual framework 

A conceptual framework is a framework that the researcher believes best explains the 

natural course of the subject under investigation (Camp, 2001). It is linked to the 

researcher's conceptions, empirical study, and essential theories for advancing and 

systemizing his or her expertise. It is the researcher's description of how the research 

question will be investigated. The framework allows the researcher to more readily 

specify and clarify topics inside the study's problem (Imenda, 2014). A conceptual 

framework is the simplest way through which a researcher presents the asserted 

remedies to the problem defined (Dickson et al., 2018). It accentuates the reasons why 

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a research topic is worth studying, the assumptions of a researcher, the scholars 

researcher agrees with and disagrees with and how the research approach is 

conceptually grounded (Camp, 2001).  Asghar et al. (2006) opined that conceptual 

frameworks can be ‘graphical or in a narrative form showing the key variables or 

constructs to be studied and the presumed relationships between them.  

 

The study adopted the Crunch model from Wisner et al. (2003) (Figure 2.4) and is based 

on the idea that an explanation of disasters requires us to trace the connections that link 

the impact of a hazard on people with a series of social factors and processes that 

generate vulnerability. The explanation of vulnerability has three sets of links that 

connect the disaster to processes that are located at decreasing levels of specificity from 

the people impacted upon by a disaster. The root causes lead to dynamic pressures that 

explain how the unsafe conditions have arisen and persisted. Root causes are connected 

with the function (or dysfunction) of the state, and ultimately the nature of the control 

exercised by the police and military, and with good governance, the rule of law and the 

capabilities of the administration as seen in the example given in figure 2.4. Root causes 

reflect the exercise and distribution of power in a society. People who are economically 

marginal (such as urban squatters) or who live in environmentally ‘marginal’ 

environments (isolated, arid or semi-arid, flood prone coastal or forest ecosystems; 

steep, flood prone urban locations) tend also to be of marginal importance to those who 

hold economic and political power. This creates three often mutually reinforcing 

sources of vulnerability (Blaikie et al., 2003). Firstly, people's behaviours are likely to 

generate increased levels of vulnerability if they only have access to insecure and 

unrewarding livelihoods and resources. Second, government initiatives aimed at hazard 

reduction are likely to be low on the priority list. Third, those who are economically 

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and politically marginal are more likely to lose faith in their own self-defence 

mechanisms and in their own local expertise. Even if they still believe in their own 

abilities, their economic and political marginality, as well as limited or uncertain access 

to resources, may have caused the ‘raw materials' or labor time required to vanish.  

 

Negligence on the part of government as well as municipal assemblies have led to the 

selling of inhabitable lands in the municipalities to people for habitation by the 

landowners and custodians. None enforcement of government policies and sanctions 

have given people the audacity to purchase properties in reserved areas due to their 

hazard-prone state putting the lives of innocent ones at risk. Efforts from the 

government as well as the municipal assemblies will educate people more on mass 

wasting event in the Ga South and Weija-Gbawe Municipalities.  

 

Land tenure issue of land tenure system in Ghana also leaves much to worry about. 

Lands in Ghana can be owned by the state or customary. State land is land compulsorily 

acquired by government through the invocation of the appropriate legislation. These 

lands are vested in the president on behalf of, and in trust for, the people of Ghana. This 

land is managed by the Lands Commission whose role is to: acquire and manage public 

lands; advise government on land use; advise the government, district assemblies and 

traditional authorities on land development and coordination; and maintain a register of 

all land titles (Gough and Yankson, 2000). In contrast, chiefs, or family heads, are still 

the custodians of customarily held land. However, they have to seek the consent and 

concurrence of the Lands Commission before disposing of or developing any portion 

of their land. The 1969 constitution removed the right to freehold tenure, but land may 

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be sold and held as leasehold. The sale of stool land is managed by the chiefs and elders 

or family heads (Gough and Yankson, 2000). 

 

The Town and Country Planning Department (TCPD) is also involved in land 

management, as it is in charge of setting goals and criteria for land use and 

development, as well as developing plans to guide growth and development. The 

TCPD, on the other hand, lacks the requisite resources to produce all of the needed 

planning scheme layouts. As a result, land is being sold at a much faster rate than the 

blueprints can be produced. As a result, leaders use surveyors who aren't always 

prepared to draft blueprints. 

 

As a result, the layouts are frequently unprepared and lack suitable public places. 

Consequently, most of the state and vested land schemes are approved before 

development takes place, whereas most development on stool land remains unapproved 

(Gough and Yankson, 2000). Cobbinah and Darkwah (2017) emphasized that 

traditional political authority function as guardians of nearly 80% of all land in Ghana, 

and frequently allocate land for development projects without following urban planning 

rules or informing urban planning organizations. This at the end of the day leads to 

improper city planning allowing people to reside in hazard prone areas as development 

preceded planning. 

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                               The Progression of Vulnerability