BUILDING RESILIENT, INCLUSIVE AND SUSTAINABLE

CITIES

Natural disasters (Flooding and landslides)

in the City of Kigali

8TH NOVEMBER 2018

Presentation content

1. Introduction

2. Sustainable Development Goals and National Development Goals

3. Natural disasters (Flooding and landslide) in the city of Kigali, their impacts and data gaps.

4. Partners, stakeholders and organisations involved in policy creation, implementation or evaluation in relation to flooding risks reduction.

5. Research projects for flooding and landslides risks reduction in the city of Kigali and research questions to be addressed (Resilience, Inclusivity and Sustainability).

Need for urban disaster management

Cities and towns need strategies and effective methods for analyzing changing risk and planning alternatives to natural hazards in urban informality to optimize their economic production.

Currently, in many cities in the developing world, spatial data on natural hazards are generalized, outdated, or even non-existent for sustainable natural hazards planning and management.

There is a research gap in designing innovative approaches for disaster risks management .

Sustainable Development Goals for Disaster risk reduction

United Nations Conference on Housing and Sustainable Urban Development (Habitat III): is supported the development of disaster risk reduction

strategies and periodical assessments of disaster risk caused by natural and human-made hazards.

SDG11 is about making cities and human settlements inclusive, safe, resilient and sustainable.

Target 11.5 of SDGs seeks to significantly reduce the number of deaths caused by disasters

Target 11.b Adopting and implementing integrated policies and plans towards inclusion, resource efficiency, mitigation and adaptation to climate change, resilience to disasters, and develop and implement a holistic disaster risk management at all levels by 2020.

SDG 13 is about to take urgent action to combat climate change and its impacts 13.1 Strengthen resilience and adaptive capacity to climate-related hazards and natural

disasters in all countries.

13.3 Improve education, awareness-raising and human and institutional capacity on climate change mitigation, adaptation, impact reduction and early warning.

Sendai Framework for Disaster Risk Reduction 2015 - 2030

Policies , plans and regulations for Disaster risk reduction in the city of Kigali

Rwanda National Urbanization Policy: Promotessustainability and resilient by developing resilient, low carbon, and safe and healthy urban environments;

• Vision 2020 : Out of six pillars of the Vision 2020, the fourth pillar focuses on infrastructure development and includes land use management and urban development;

2013 Kigali City Master Plan: Focuses on urban sustainability framework by addressing environmental aspect including protecting Urban areas prone to flooding and landslide, limiting increasing of urban temperature by creating public green spaces;

• Economic Development and Poverty Reduction Strategy (EDPRS 2): emphasises that urbanization needs to be adequately planned and regulated. It also stresses the need for increased citizen participation in the process of planning and development.

Existing Land UseRwanda

Area: 26338 Km2

Pop: 11.7 millions

Topography: Hilly Alt.1000-2000m

Study area The city of Kigali, Rwanda

One of the five provinces in Republic of Rwanda

Spontaneous

Established 1907Total Area: 731 km2

City Pop. : 1.3 million (2011)Household size: 4.7

Gross Density: 1778 hab/ km2

3 Districts35 Sectors161 Cells

1061 Imidugudu (Village)Planned / formal

State of hazards in Kigali city

Subject 1Date 1

• Hyper concentrated flows related to erosion processes originated by heavy rains and affect the pyroclastic soils cover along rills as well as on the inter-rills areas.

• Flashfloods are originating from heavy rains as well, and they are having less sediment load than the hyper concentrated flows.

• Landslides on the open slope sections, affect the triangular facets located at the base of the slope; and are classifiable as “debris avalanches”

• Mudflows from flow slides that originate higher up in the catchment.

The impact of flooding and landslides in Kigali (Social, Health, Economic and Natural systems)

Health: The Ministry of Disaster Management and Refugees (MIDIMAR) says up to 116 people have been reported dead while another 195 were injured as a result of heavy rain between January and April 2018.

Social and Economic: Disasters linked to rain have also swept away 4,560 hectares of crops and destroyed 370 housing units. 12 roads, 7 churches and 18 bridges were destroyed while 700 domestic animals were killed.

Natural systems: Landslides have swept away many hectares of the arable land and vegetation cover.

Subject 1Date 1

17/12/2018

1987 1999 2009 2014

Modelled density 2040

One of the fastest growing cities in Africa

Driver 1: Urban growth

Driver 2: Climate Change

• Temperature

• Rainfall : Extreme rainfall storm, overflow of river banks, and change in hydrological conditions of the rivers should be dominantly responsible for runoff, abnormal floods and ravines.

17/12/2018

Rooftop

Some interception

no infiltration max runoff

Vegetation, bare soil

Interception infiltration

less runoff

Drain no interception

Some infiltration guided

runoff

Murrum road

No interception min.

infiltration less runoff

Stakeholders and organisations in relation to disaster risks reduction

Pre-disaster Phases Post-disaster Phases

Risk

identification

Mitigation Preparedness Emergency

response

Rehabilitation and

reconstruction

Hazard

assessment

Physical/Struct

ural mitigation

works

Early warning systems

Communication

systems

Humanitarians

assistance/rescue

Rehabilitation/reconstru

ction of damaged

critical infrastructure

Vulnerability

assessment

Land use

planning and

building codes

Monitoring and

forecasting

Clean-up,

temporary repairs

and restoration of

services

Budget management

Risk

assessment

Economic

incentives

Shelter facilities

Emergency planning

Damage

assessment

Revitalization of

affected sectors

GIS Mapping

and scenario

building

Education

training and

awareness

Contingency

planning(Utility

companies/Public

services)

Mobilization of

recovery resources

Incorporation of

disaster mitigation

components in

reconstruction

Solutions to decrease vulnerability and Resilience strategies

• Improve drainage system

– City engineering larger

drainage channels

– Community self-help cleaning

• Guard green area

• City planning must guard open green space

• Increase resilience at house level

– Elevate houses

– Small dikes surrounding house

Drainage system aspects

What have been so far? Gaps and issues

Stakeholders involvement

• Duplication of responsibilities (For example, 1. Disaster Management Centre covers a combination of all hazards while Rwanda Environmental Management Agency is mandated to carry out all environmental issues including hazards; 2. Disaster Management Centre and Rwanda Environmental Management Centre are responsible to the Government for hazards and environmental management but it is not clear whether or not they have power on local structures whereby these (local structures) are under the Ministry of Local Government and Community Development);• Focus purely on technical issues like channels construction and little attention of an adequate conceptual framework for hazards management;• A great effort in legislative and policy framework.

Participation process

• Little involvement of citizens in hazards mitigation even if there are community works once a month;• Strong involvement of “grass root communities of interests” in hazards mitigation (construction of channels for runoff drainage, plantation of trees on the top of Kigali mount, collection of waste once a week);

Disasterresiliency

• Lack of human resources and equipment specialized in hazardsmitigation;• Several channels have been constructed by Urban Infrastructure and City Management Project (UICMP) and offer some control over rivers but in some cases they have created a false sense of safety to the people living nearby and have actually increased losses when an extreme event surpasses design specifications;

Subject 1Date 1

Challenges of Urban Risk Assessment

• High demand for assessments to be used in risk based city planning and limited capacity in city planning departments to assess the long-term flooding and landslides

• Lack of comprehensive disaster risk management program or disaster response plan for the City of Kigali

• Lack of flexible approaches to risk assessment

• Inadequate capacity of stakeholders and funds to conduct risk assessments

• Lack of accurate and reliable data mostly hydro-meteorological data.

• Lack of an holistic for community-based disaster risk management (CBDRM).

Subject 1Date 1

Potential research topics

• Towards improved hydro-meteorological forecasting of flash flood

• Community engagement based decision support systems for flood risk resilience.

• Analyzing changing risk and planning alternatives to natural hazards in urban informality in the city of Kigali

Subject 1Date 1

Tools to evaluate best risk reduction alternatives

• Cost Benefit Analysis (CBA) is used to compare costs and benefits of a one specific measures or a set of alternative measures over a period of time for a. CBA assesses the measure(s) mainly on the basis of the efficiency criterion. It requires the monetization of all the effects. The effects that cannot be expressed in monetary terms will be usually described in their original unit of measurement.

• Cost Effectiveness Analysis: (CEA) has most of the features of CBA, but does not require the monetization of either the benefits or the costs (usually the benefits). CEA does not show whether the benefits outweigh the costs, but shows which alternative has the lowest costs (with the same level of benefits). CEA is often applied when the norm for a certain level of safety has been set. CEA analyzes which types of solution is the ‘cheapest’ given a certain level of safety standard.

• Multi Criteria Analysis (MCE) is a tool that allows comparing alternative measures on multiple criteria. In contrast to CBA, MCE allows the treatment of more than one criterion and does not require the monetization of all the impacts. MCE results in a ranking of alternatives.

Alternative 1: Engineering solutions

• Take out the soil in the landslide prone areas

• Create storage basins that will retain the floods and debrisflows

• Create water channels to guide the water

• Create a monitoring and early warning system

Alternative 2: Ecological solutions

• Take out the soil in the landslide prone areas

• Use soil nailing in the upper slope to reduce the landslide susceptibility

• Create water tanks that will retain some of the floods

• Create water channels to guide the water

• A barrier of oak trees that will retain some of the debris flows and mudflows

• Create a natural park which will stop further development

Alternative 3: Relocation of the most dangerous areas

• Evacuation of the elements at risk in the most endangered areas.

Key research questions to be addressed

Resilience

• Is community involvement in the planning process an added value to flood resilience?

Inclusivity

• How can inclusivity influence the flood management processes at different decision-making stage?

Sustainability

• Is the concept of sustainability economically viable for flood management considering climate change, urban and population growth?

Subject 1Date 1

Thank you

Possible future scenarios

Name Land use change Climate change

Scenario 1 Business as usual Rapid growth without taking

into account the risk

information

No major change in climate

expected

Scenario 2 Risk informed planning Rapid growth that takes into

account the risk information

and extends the alternatives in

the planning

No major change in climate

expected

Scenario 3 Worst case Rapid growth without taking

into account the risk

information

Climate change expected,

leading to more frequent

extreme events

Scenario 4 Most realistic Rapid growth that takes into

account the risk information

and extends the alternatives in

the planning

Climate change expected,

leading to more frequent

extreme events

• Which risk reduction alternative is the best now?

• Which risk reduction alternative is the best for each of the scenarios?

• Which is the most “change proof” risk reduction alternative?

• In which scenario does the risk increase most?

• In which scenario do we have the best development?

• What would be the added effect of flood hazards on the results?

CONCLUSIONS

Risk information and the role of GIS

• Geoinformation science and earth observation play a key role in the generation of spatial information on the three components of probability, vulnerability and cost, their integration into risk information, and the use of this information in urban risk management.

• Risk information, when presented spatially and for all threats, is needed by local authorities to take decisions on how to reduce risk for particular areas, either by reducing the hazard probability (e.g. structural measures like dikes) or by reducing the vulnerability(e.g. restrictive zoning, building codes). Risk information also forms the basis for a proper emergency response planning.