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Road geohazard risk management: Sierra Leone case study

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Written by Fatima Arroyo Arroyo, Xavier Espinet Alegre, and Akiko Toya



This project, “Institutional Capacity Review and Target Setting for road geohazards Management” aims at assessing the current capability of various key institutional actors—but primarily the Sierra Leone Roads Authority—in Sierra Leone’s roads and transport sector, with the intent of evaluating their capability to formulate and implement policies and plans in the area of road geohazards management. Financed by the Global Facility for Disaster Reduction and Recovery (GFDRR) through the World Bank, the project also involves a physical assessment of potential risk sites along a number of major road corridors in the capital, Freetown, primarily through observation of both naturally occurring and human-generated activities and events around these sites.

The findings of the assessment are used to offer a set of recommendations to the above-mentioned institutions for improving the mitigation effectiveness of their policies, plans and initiatives. The project evaluates both institutional and technical capacity, as well as examine climate change-related issues such as landslides and flooding that are negatively impacting the urban transport infrastructure.


Sierra Leone’s population of about 3 million people in 1975 has burgeoned to about 7.8 million in 2019. Between 2003 and 2014, the country’s economy grew at an impressive average annual rate of 7.8 percent, but in 2015 it sharply contracted, by 21 percent, following a combination of the 2014– 2016 Ebola outbreak and a decline in the price of iron ore, Sierra Leone’s main export product. Per capita annual income, estimated at US$506 in 2018, remains below its pre-Ebola level of $660. The difficulties generated by such low income are compounded by an annual population growth rate of about 2 percent. In 2018 the Leone, the national currency, depreciated by 12.0 percent year-on-year, underpinned by the widening of the current account deficit to 14.0 percent of GDP (from 11.7 percent in 2017), following a sharp drop in exports earnings.

Understanding Sierra Leone’s road geohazards

The economic hardships of the past half-decade, along with Sierra Leone’s tropical monsoon climate, work together to create a potential powder keg of road geohazards that is continually waiting to explode given the right circumstances. Yet the budgetary limitations of the country’s low-income economy is one factor that constrain its ability not only to respond post-crisis if a destructive climatic event were to strike, but to put in place pre-crisis, preventive and resilience-building infrastructural measures in the first place.

Freetown averages 3,657 mm (144 in.) of rain a year—well over three times the global average of 990 mm (39 in.). That amount of rainfall—from July to September it rains almost every day—would be a challenge to any road geohazards risk management program, and can generate a range of potential issues—from floods, landslides, debris flows, and siltation to landslides, erosion of embankment slopes, damage to road surfaces, and impaired access to critical buildings and locations throughout the city. A number of these geohazards are further exacerbated by human-initiated activities, including garbage deposition in street gutters, siltation of storm drains, unplanned construction on hilly terrain, and deforestation that accelerates erosion by exposing the soil directly to heavy rain, and by ridding forest floors of the dense network of roots that stabilized the top soil and kept it in place.

The vulnerability of Freetown to geohazards was vividly uncovered in the catastrophic landslide that occurred in August 2017. A November 2017 World Bank report, "Rapid Damage and Loss Assessment of August 14th 2017 Landslides and Floods in the Western Area," summarizes the institutional, infrastructural, policy, and programmatic challenges that amplified the physical effects of the landslide and resulted in the deaths of 1,141 people:

  • The road system in Freetown suffers from three major deficiencies: inefficient and inadequate network, poor design and construction, and no effective maintenance
  • The institutional arrangements for the delivery of infrastructure and services are complex and inadequate, with several agencies having responsibility for various aspects of urban transport, hence overlapping of mandates while some functions are not specifically allocated to any one agency
  • Roads need to be reviewed, repaired, and reconstructed to better withstand future flooding risk and enhance the resilience of the road network
  • Institutional strengthening is needed to enhance the transport asset management system and to maintain the transport infrastructure network

Summary of Current Approach to Road Geohazard Risk Management Practices

Several institutions support road geohazards / natural disaster management in Sierra Leone. These are the Office of National Security (ONS), Sierra Leone Roads Authority (SLRA), Road Maintenance Fund Administration (RMFA), Freetown City Council (FCC), Sierra Leone Police (SLP), and the line ministries of these institutions.

The current approach (not guided by any formalized strategy) to road geohazard risk management practices is not effective; there is no specific structure or framework. At SLRA and other institutions, personnel and equipment may be available to address issues of geohazards or natural hazards but they respond only when the need arises. Therefore, geohazard risk management practice is more reactive than proactive. In some cases, due to the re-occurring event of flooding as a result of blocked gutters and storm drainages, proactive actions are taken by SLRA and FCC for drainage/gutter-clearing before the rains get heavy during the months of July and August.

Assessment of Current Practices and Capability

There is no specific assessment process currently employed for geohazard risk management by the institutions. A reactive situational process is what seems to be in existence. Events triggered by geohazards are reacted to rather than mitigated. Emergency and prevention risk response can be slow—likely due to overlapping responsibilities among the institutions, resulting in "who is to do what" and other bureaucratic protocols before action is finally taken.

Almost all roadside cuttings within Freetown are unprotected – this is a major factor in geohazards risk such as rockfalls, erosion, debris and mudflow into gutters and on road surfaces, especially when it rains heavily. Current road designs make use of the Southern African Transport and Communication Commission (SATCC) standards.

Even though the legal instruments (acts, regulations and policies) on land use for construction, planning, deforestation and protected areas are all adequate, strict enforcement of the regulations has been challenging.

Human activities (in planned and unplanned settlements) such as construction of "baffas" (traditional temporary shelters) for street trading, dumping of household waste and garbage, and stone mining from exposed rock surfaces along the road all contribute significantly to geohazard risks in Freetown.

In terms of financing road geohazard risk management practices, it is worth noting that geohazard risk management is not specifically budgeted for within Ministries, Departments and Agencies’ (MDA) institutional budgets; it is financed from other operational contingencies. In cases of emergencies, the Ministry of Finance may provide some funding and their effort is complemented by donor support agencies, local private companies and individuals.

Target Setting and Improvement Actions

The word "geohazard" was relatively new to almost all the institutions that were interviewed and most individuals working for them. Therefore it makes it difficult and a challenge to relate the roles of these institutions towards road geohazards.

As our team found out from interviews with senior personnel at these institutions whose activities and mandate—as documented in the checklist tables in the appendix—are supposed to be geared towards road geohazard risk management, the level of competency among them can generally be classified in the low to medium range, skewing mainly towards the low range.

SLRA, being the focal institution for road geohazard risk management, has qualified staff that are knowledgeable in risk management but are deployed in other work areas where they are less utilized, with no responsibilities in the area of road geohazard risk management.

Statement on the Target Capability for Assessed Item(s)

Institutional capacity and coordination

Generally, SLRA and the Office of National Security have adequate technical and coordination staffs but their expertise is limited when it comes to managing road geohazards risks and events. Therefore the institutional and coordination capacity is low for managing risks and events relating to road geohazards that will affect the transport sector.

Systems planning, engineering and design

There is no mechanism in place to identify risk on the road network; data are scarce for making informed, data-driven decisions, or evaluating all sites in order of priority to know which of them most urgently need proactive measures. Solutions to mitigate or respond to road geohazard events are therefore ad hoc and often only temporary in the form of a Band-Aid while the cut requires sutures. There is a need for reviewing road engineering practice and design if road geohazards should be mitigated; very little use is made of currently available road slope design and protection methods (for example, interlocking block walls or gabbion baskets). There is no comprehensive database that holds information about the condition and status of all paved roads; existing data are either incomplete or inadequate for decision making.

Operation and maintenance

The technical capabilities for operation and maintenance within SLRA are adequate but the shortfalls are the lack of an asset management framework and the omission of road geohazards in its operations and maintenance strategy. Information dissemination to the public about road geohazard risks due to climate change events, for example, is not effective. It is more of a reactive action done by radio broadcasts and sometimes through community-based organizations. Warning signs and traffic management during geohazard events are inadequate due to challenges in rerouting traffic to alternative roads.

Contingency programming

There is an existing emergency response plan with ONS for security and other disasters but not for road geohazards. The emergency response plan requires reviewing. Emergency response activities are coordinated by ONS by alerting relevant institutions to go into operation. Remedial or recovery measures do not necessarily involve a “build-back better” method but a quick fix. A “build-back” approach is normally limited to very high-priority sites or areas in the case of road geohazards, and this is usually a slow process due to inadequate funding.


An assessment of the institutional capacity of the SLRA and other MDA’s with regards to their response to geohazards emergencies and management was conducted successfully. It was found out that there is need for a documented national framework including emergency response plan for natural disaster and specifically for road geohazard risk management.

It can be concluded that, lack of proper management system for data collection; inadequate funding for geohazards and natural disaster; low staff skills to meet current practices in disaster and risk management; the need to review engineering designs for construction of slopes with better aesthetics and stability; inadequate use of non-structural measures (e.g. early warning systems) and enforcement of laws, regulations and policies regarding land use and management are contributing factors leading to the very low performance in road geohazards risk management.


It is recommended that a standalone agency for national geohazard risk management be setup under the Ministry of Transport and Aviation. SLRA, the institution whose mandate is to manage all major roads, must have a well-functioning department for road geohazards risk management and that other key supporting institution should have a clear knowledge about their roles, responsibilities and contribution(s) expected towards geohazards and natural disasters. Adequate funding for geohazard risk management should be provided for in the national budget and should be available to fund planned activities in institutions concern with geohazard risk management.