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1. FLOOD RISK MANAGMEENT
Challenge for Urban Amman downtown
Amani Abdo
Urban design & planning

2. Flood in Amman down town, march 2019

3. 1. INTRODUCTION
1.1Aims
1.2 Target groups
1.3 Objectives
2.FLOOD RISK MITIGATION
1.4 urbanization
1.5 Climate change impacts
2.1 Flood hazard
3.4 flood damage potential
2.2 Flood risk assessment
2.3 Flood risk management
2.4 Strategic approach to urban flood management
2.5 Flood risk prevention
2.6 Flood risk mitigation
3. LAND-USE AND FLOOD RISK
2.7 GIS and land use-based assessment in natural hazard
management
2.8 IFM & land use
3.2 impacts of land use on flood hazards
3.1 interactions between flood risk in the land and water
environment
3.3 effect of specific development intervention on flood hazards
3.5 Flood damage potential
3.6 Flood vulnerability
3. Land use planning and flood management
3.1.1 Land use Planning
3.1.2 Flood Management
3.2 planning processes
3.2.1 Land use planning processes
3.2.2 Flood management planning processes
3.2.3 other related planning processes
3.3 roles of land use planning in flood management strategies
2.6.1 Reducing Flooding
2.6.2 Reducing Susceptibility to Damage
2.6.3 Preserving the Natural Resources of Flood Plains
Land use implementation tools
Regulatory
Financial
Economic
Behavioral
3.4 tools and mechanisms for interaction
3.4.1 Flood hazard maps
3.4.2 Flood risk assessment of strategies and plans
3.4.3 Flood risk assessment for particular planning applications
3.4.4 Environmental Assessment
4. DEVELOPMENT MANAGEMENT TECHNIQUES IN
THE FLOOD HAZARD CONTEXT
4.1 paths of government intervention
Legal and institutional framework
Rights powers an obligations
Clear definition of roles
Institutional coordination

4. 1.1 Research Problem
Land use and infrastructure planning has traditionally addressed problems
with policies regulating the location and intensity of urban activities, often
based on assumptions about urban and environmental dynamics that are
rarely revisited (Alberti, 1999; Neuman, 2005). A key challenge of planning
for urban sustainability is to understand the dynamic multi-scale and multi-
level relationships between different social, economic and environmental
systems in a local or regional context.
The link between the planning process and urban infrastructure is extremely
important; specifically the link between land use planning and sewage
infrastructure. One measure of this link could be the relationship between
population distribution and drainage infrastructure across a metropolitan
area. Many cities of Jordan including amman have suffered due to lack of
effective planning practices. The land use patterns and population
distribution in the amman metropolitan area must be examined for its
relationship with the transport network which serves as the lifeline for any
modern city.

6. Aims
This Tool aims to:
• Identify the processes and policy principles that necessitate a linkage of land use planning in
integrated flood management
• Provide an overview of land use planning instruments considered applicable in the flood management
context
• Identify the challenges and opportunities to a closer linkage between the various sectors concerned
• Provide guidance as to how those sectors can work together
Target Group
The Tool is primarily written for flood managers at municipal and higher administrative levels to facilitate the
necessary dialogue with land use planners on local, regional and catchment levels, urban and agricultural
planners, transportation planners, developers of individual land parcels etc.
Objectives
Background aspects of city, like topography, hydrology, socio-economic status, weather pattern ,land use and
infrastructure , with special reference to drainage
Root causes and immediate and long-term impacts of past flood incidences .
Master Plan provisions in relation to flood mitigation and management practice including regulatory or
voluntary efforts.
Existing Structural and non-structural flood mitigation measures-achievements and shortcomings.
Rescue, response and coping mechanism during past flood events and lacunae.
Failures of the present mitigation and coping mechanisms
Strategies for future flood mitigation and management by assessing the past flood management practice of city
and state government.

7. To reduce the underlying causes of flooding and ensure continuing
development gains, cities must prioritize risk-based land use planning. Globally,
urban centers are at a high risk of flooding, not only from more frequent and severe
hydrometeorological events and sea-level rise, but also from rapid, sprawling, and
often unplanned urban development that is outpacing the construction or
improvement of drainage infrastructure. A risk-based approach to land use planning is
crucial to cities in both developed and developing countries.
Land use planning to manage flood risks must balance competing needs: it
should seek to maximize net benefits from waterfront economic and recreational
activities and ecosystem services, while ensuring minimum loss of life and property
through safe location, safe construction, and safe activities. By supporting the spatial
integration of “gray” (conventional) hard-engineered infrastructures with “green”
infrastructure to manage water resources and protect against flooding, land use
planning can help to create a balanced urban water ecosystem.
Land use planning offers many opportunities to manage floods in all stages of
the disaster risk management cycle. Planning measures can minimize
development in flood-prone zones; reduce water runoff through development controls
for flood risk mitigation; designate routes and open spaces for better response and
recovery efforts; mitigate damages from unavoidable floods; and accommodate urban
growth and expansion in flood-safe areas— including through resettlement and
reconstruction, when it is important to promote “build back better” practices within a
risk-based land use planning framework.
Summary

8. Cities have used several land use tools to manage floods with varying degrees of success.
Spatial plans provide the key reference to guide land use based on flood risk assessments and
may be prepared at various administrative levels, from national policies with general directives to
municipal plans with comprehensive layouts. Cities have traditionally sought to manage floods with
regulatory instruments, such as zoning (to designate floodplains or open spaces) and building
codes (to ensure flood-resilient structures), but enforcing compliance has been difficult. More
recently, cities have experimented with economic instruments, such as land-based financing and
performance incentives. Influencing community behavior through risk communication and
participatory methods is vital for supporting flood risk reduction. To create realistic plans that are
acceptable to the community, the planning process must be supported with a participatory framework
for risk diagnostics and communication, along with plan preparation, implementation, and monitoring.
Ultimately, different land use tools must be used in combination for effective implementation.
Integrating flood risk in the land use planning process can be challenging, requiring
coordination among multiple stakeholders and institutions, both formal and informal, as well
responsible decision making. Decision makers may be motivated to push for highly visible
structural measures, which can show constituents that flood risk is being addressed. At the same
time, resettlement is unpopular in both developed and developing countries. In developing countries,
implementing land use plans is further confounded by the complexities surrounding informal
settlement and unclear tenure, as well as by lack of capacity and resources. Ultimately, successful
land use planning for flood risk management requires investment in two areas: (i) educating decision
makers and communities about the flood risk and role of land use planning in managing it; and (ii)
building sufficient technical and governance capacity to formulate, implement, and manage a flood
risk–based land use planning process. This paper offers policy makers and practitioners an
overview of the key aspects of land use planning used to manage flood risks in cities across
the world. It includes examples from developed and developing countries to provide insight into what
has worked in different contexts. It does not provide prescriptive solutions or step-by-step
methodologies, since approaches will vary by context. Solutions and methodologies will depend on
local land use challenges and institutional capacities, on the scale at which land use planning is
undertaken, and finally on the local land use planning culture and land tenure regime, apart from

9. 1. Introduction
The way land resources are utilized has a decisive influence on development prospects of societies. In
many places the most valuable land resources in terms of soil fertility, urban development space,
infrastructure location (e.g. transport links) etc. are liable to flooding. Taking a closer look at the issue
of flooding, there are two major aspects that connect land use and flooding:
• The location of values and key components of the economy on flood plains provides economic
benefits (i.e. the primary reason for developments being placed there) and at the same time creates
risks for the society in terms of flood loss potential.
• The development of land has consequences on the flow of water on the one hand, either by
accelerating runoff through reducing the infiltration capacity of soils or obstructing the natural
drainage system, as well as sediment and pollutants on the other hand.
Naturally, since these processes are better understood for a couple of decades, calls have been that
planning practices in the different sectors and groups dealing with land use planning on the one hand
and flood protection or flood risk management on the other, should be interlinked or harmonized.
In its worst form a traditional and reactive approach would be to develop flood prone land without
knowledge of the prevailing flood hazards, and to provide local flood defences for the area in an ad-hoc
manner once flooding has occurred.
Contrary, the approach promoted in this tool and largely recognized as the way forward is to take
development decisions based on the knowledge of the prevailing and expected future risks and to adapt
development planning according to the degree of risk faced and the risk a particular society is willing
and able to accept.

10. 1.1 Urbanization
Urbanization disrupts natural
drainage patterns; natural
watercourses are destroyed and the
natural retention of runoff by
plants and soil is removed. By
changing pervious natural surfaces
to less- or non-pervious artificial
surfaces, the storm water runoff
rates and the total runoff volumes
will increase as a result of a
declining natural water storage
capacity of the soil. All these
factors are leading to an increased
risk of urban flooding. Change of
natural water storage as a
consequence of urbanization also
causes significant changes to the
temporal characteristics of runoff
from an urbanized area, such as
shortening the runoff travel time
and giving to the event a flashing
appearance.

11. 1.2 Climate change impacts
Climate change is one of the greatest environmental, social and economic threats faced by
the planet. Climate change scenarios generally imply an increase in rainfall variability and,
on global average, an increase in total precipitation, which could lead to even more
frequent and severe natural disaster and floods.
Human induced climate change is expected to continue in the coming decades (IPCC,
2001a) with considerable effects on human society and the environment. The magnitude of
the impacts strongly depends on the nature and rate of future temperature increase.
Consequences of climate change include an increased risk of floods and droughts, losses of
biodiversity, threats to human health, and damage to economic sectors such as forestry,
agriculture, tourism and the insurance industry (IPCC, 2001b).
In Europe losses have increased substantially over the past 20 years to an average of EUR
10 billion in the 1990s. Four of the five years with the largest economic losses have
occurred since 1997 (EEA, 2004).
A recent study by the European Environmental Agency (EEA, 2004) summarises the
current consensus within the European research community. It states that there is growing
evidence that changes in frequency and extent of climate extremes are likely to be caused
by a shift of the mean climate to more extreme conditions, and more and stronger
deviations from this mean.
Fighting climate change is a key environmental priority for the European Union.
Substantial reductions in emissions of greenhouse gases will be required to ensure that
Europe meets its short-term emission targets. Adaptation measures to manage the negative
impacts of climate change also need to be put into place.

12. 1.3 Flood hazards
Natural hazards and disasters are the products of an interaction between numerous aspects,
such as climatic, social, economic, institutional and technical, that are differently addressed
for rural and urban conditions (Andjelkovic, UNESCO, 2001).
An “environmental approach” to flood hazards is based on the view that both social and
physical environments influence the creation of flood hazards and disasters. The
environmental approach, proposed from Parker in his book “Floods” (2000), is focusing
primarily upon the social explanation of flood hazards and disasters without denying
contributory physical causes.
Flood hazards and then risk should be viewed as endemic product of a natural, physical
and biological environment usually heavily modified by the social, economic and political
environment.
The term risk has been defined in several ways in the natural hazard literature. According
to the definitions proposed by Kron (2002), three variables determine the “risk”: hazard,
vulnerability and exposure.
• – Hazard: the threatening natural event including its probability/magnitude of
• occurrence;
• – Exposure: the values/humans that are present at the location involved;
• – Vulnerability: the lack (or loose) of resistance to damaging/destructive forces.
Most important is the distinction that is drawn between the words hazard and risk
(Gouldby and Samuels, 2005). A hazard does not automatically lead to a harmful outcome,
but identification of a hazard does mean that there is a possibility of harm occurring, with
the actual harm depending upon the exposure to the hazard and the characteristics of the
receptor.

13. Vulnerability to flood disasters comes through various forms: exposure to floods as a result
of locating in flood-prone areas, occupying a dwelling which has little resistance to floods,
the quality of buildings, lack of protections from floods, weaknesses of the population
related to age, gender, health status, infirmity. Inability to avoid or recover from a flood
disaster and low levels of protection or assistance are also contributory social factors.
Both vulnerability and exposure to floods are viewed as key causal factors of risk: the
approach involves evaluating the full range of traditional approaches to flood hazard and
disasters as well as modern technological ones.
This kind of approach involves viewing the problems of flood hazards and disasters and
long-term safety survivability within the context of sustainable development. Sustainable
communities are those that are able to weigh up these risks and seek to reduce the
vulnerability of their people to natural hazards, so they seek to build social and economical
resilience to disaster (Parker, 2000).
Moreover, central to the concept of hazard is the notion that humans interface with floods:
a flood is not hazardous unless humans are somehow affected. Hewitt (1983) takes this
further by stating that a hazard refers to the potential for damage that exists only in the
presence of a vulnerable human community.
Flood exposure is a measure of the human population, land uses and investment located in
flood zones and at risk of flooding, and increasing exposure is a prime, contributory cause
of flood hazards and disasters.
A common method of measuring flood exposure is to count the number of properties of
different types that occupy a floodplain or other flood risk area such as coastal flood zone.
There is a substantial evidence from different parts of the world that exposure to floods is
growing rapidly as human occupation of floodplains and flood-prone coastal zones
intensifies.

14. 1.4 Flood damage potential
The location of economic values on floodplains or the investment into floodplain areas has
played a major role in the development history of most countries.
The benefits derived from the floodplains are provided at a risk.This flood damage can come in
various forms to buildings, goods, crops, infrastructure, or the environment. 4
By taking decisions on land-use and on placing such values on land liable to flooding humans
have an influence on the flood damage potential. Therefore, in modern flood management
approaches land-use planning and regulation plays a vital role in controlling the flood damage
potential to acceptable levels.
In this context it seems important to consider that society through political processes and
individual choice has to take decisions on the level of flood risk it is willing to accept. Those
choices are sometimes explicitly formulated in form of policy documents, laws or similar
instruments.
While employing such statistics to raise the level of flood risk awareness and to point at
unreasonable increases in flood risk can be beneficial, they tend to oversimplify the issue if
employed as “stand-alone” argument. When using such figures several aspects which are
normally not taken into include
• the benefits that the use of floodplain areas provides to society
• the possible lack of less risk-prone alternatives
• the level of protection that existing flood defences and flood-proofing measures .
It is therefore essential to take a broader view of risk-benefit relationships in devising flood
management policy. The prime economic indicator for success of flood management policies
should be the net-benefits that are derived from the floodplains, based on an environmentally
sound and sustainable approach.

15. 1.5 Flood risk assessment
The urban sprawl in metropolitan areas along large rivers causes an increasing claim on
space that is merely used as floodplain and consequently spread of building activities in
places not suitable for building. At the same time potential climate changes are likely to
cause an increase in number and intensity of flood events. This mutual expansion increases
the vulnerability of urban areas to flooding and therefore the social and economic damage
in case of a disastrous flood event. Consequently, the responsible authorities are required
to adapt their policies in order to combine flood management measures, spatial
development and new strategies on protection standards. In order to evaluate the changes
of risk, it is necessary to examine the increasing exposure to floods and the damage
potential losses resulting from these floods (AquaDeltaForum, 2004).
In most cases the conventional flood management measures do not hold this integral
approach. Consequently a future challenge in urban flood management lies in the
development of innovative protection measure, in which the growing demands for space,
the consequences of potential climate changes and advanced safety standards are entirely
integrated (AquaDeltaForum, 2004).
Besides structural measures aiming at a reduction of the probability of flooding, new
approaches need to be developed to mitigate flood impacts. Legislation, land use planning
and management, zoning, urban drainage, flood insurance are some examples to modify
the vulnerability of the urban environment to flood damage.
The adoption of non-structural approaches for urban flood mitigation as structural
solutions has proved at best partial solutions. Urban planning guidelines and flood
management strategies should, therefore, be part of an integral approach to the problem
(AquaDeltaForum, 2004).

16. 1.6 Flood risk management
Risk management is the systematic approach to minimize disaster impact at all levels and
locations in a given society. It is normally based on a comprehensive strategy for increased
awareness, assessment, analysis/evaluation, reduction measures (Brezger,2004).
In addition, the framework needs to include legal provisions defining the
responsibilities for disaster damage and longer-term social impacts including spatial
planning actions.
Integrated risk management stresses the equal implementation of all possible measures and
includes risk communication and dialogue as relevant elements of risk management (ARE,
2003).
The UNESCO provides a comprehensive set of best practice for non-structural measures in
urban flood management (Andjelkovic, 2001), proposing a management planning defining
the identification of problems, opportunities and constraints, the setting of goals and
objectives (like reducing exposure of people and property to flood hazards, reducing
existing level of flood damages, minimizing soil erosion and sedimentation problems,
protecting environmental quality), the establishment of policies and priorities that govern
overall effort, and, finally, the development of criteria and standards for evaluating
systems’ performance under future development scenarios.

17. 1.7 Strategic approach to urban flood management
A combination of structural & non-structural urban flood management strategies are considered to be
complementary aspects of a comprehensive & integrated urban flood management strategy.
Non-structural urban flood management strategies
Main focus on physical interventions & investments in engineered infrastructure.
Over the centuries a variety of structures have been evolved to mitigate the flood hazard. The main
thrust of flood protection program in Jordan so far has been in the nature of structural measures.
Structural urban flood management strategies
Strategies impacts focus upon preventative action & rely predominantly on behavioral changes in order
to be effective.Particularly relevant in low income communities in tropical climates, where flooding is
inevitable and resources for infrastructure are scarce.

18. 1.8 Flood risk Prevention
Important flood risk prevention strategies to manage with floods are mitigation, adaptation
and preparedness. Mitigation, adaptation and preparedness can be summarised under the
term prevention (Plate, 2001). This section introduce this basic concepts used in flood
planning and managing.
Mitigation aims at reducing the flood event itself, through robust and sustainable local
solutions and structural measures like reservoirs or dykes, that can cope with the everincreasing
urban pressure on flood prone areas and the uncertainties created by climate
change. Keeping water out of urban areas in many instances is not the perfect solution;
accepting and preparing for some degree on flooding will in many cases be a more sensible
solution (AquaDeltaForum, 2004).
Adaptation basically means reducing vulnerability through non-structural planning
measures like restrictive zoning. At local/urban level adaptation to floods can be addressed
by strict measures such as prohibit new development in the floodplain and to proof existing
structures, or even to replace the existing development by alternative use of land towards a
reduction on floods damage.
Preparedness is the preparation of a rapid and adequate response at all times and especially
in the run-up to a flood event. It is relevant to prevent these floods, but of course this is not
always possible. Whatever is done to prevent floods from happening, and the risks of
flooding, there will always be some residual risk. In those cases the level of preparedness
can be of key importance. Reducing the adverse effects of a flood can diminish the number
of casualties and of course the amounts of losses.

19. 1.9 Flood risk mitigation
Flood forecasting: with reliable advance information/warning about impending floods loss can be
reduced to a considerable extent
Flood inundation mapping & land use planning: Satellite R. S. is extremely useful in monitoring the
dynamics of water spread
Flood plain zoning: means categorization based on admin. Legislations for planning & dev. of flood
plains for various purposes.
Flood insurance: Scheme of charging insurance premiums based on nature & location of
establishment in flood plains
Decision support system for real time flood warning & management: based on database linked to
math. Models based on hydrometereological information.

20. land use-based hazard
management

21. 2.1 GIS land use-based assessment in hazard
management
Environmental risk management needs a multi-disciplinary approach, with input and
expertise required from many fields. A wide range of simple to complex, spatial and non spatial,
quantitative and qualitative input data sets is used in environmental risk assessment
and analysis process. Due the need for using and analyzing a huge volume of the spatial as well
as non-spatial environmental hazards and exposure data in a fast and reasonably accurate way,
Geographical Information Systems (GIS) based software applications using a variety of
modeling techniques serve as powerful tools for effective environmental risk assessment
and management (Raheja, 2003).
Such applications can be used for a range of environmental risk assessment and analysis
purposes. These applications can vary from development of databases systems for simple
to complex GIS layers overlays, to complex territorial decision-making systems for study
the impact of natural disasters on the natural and artificial environment, including human
beings, properties, infrastructure, vegetation and ecology.

22. 2.2 IFM & land use
Land in many parts of the world is a scarce but crucial natural resource. Ongoing developments
such as population growth and connected issues of food security and urbanization put land and
water resources under considerable pressure. Looking at the development history of societies it
becomes evident that floodplain areas have been preferred for human settlement.
While the contribution of those flood-liable lands and the flood protection infrastructure to socio-
economic development need to be recognized, the growing risks to the development process have
become evident over the past decades in numerous examples of large scale flooding with serious
economic consequences. Flood risk in its most essential form is the product of probability of a
particular flood event times the consequence that event would have.
In another form flood risk is described as a function of the flood hazard (probability of
occurrence of a particular flood event), the exposure of human activity to the flood (flood
damage potential) and the specific vulnerability of the community affected by the flood.
The level and trends in accumulating economic values on floodplains, in particular in form of
“urban uses” encroaching on the flood plain, has in parts of the world led to discussion on
acceptable levels of flood risk and in case led to considerable changes in national flood
management policies towards limiting the flood damage potential by anti-encroachment policies.
Integrated Flood Management (IFM) as a development policy concept calls for a balance
between the development needs of society and the flood risks oriented towards the maximization
of net-benefits derived from the flood plains to ensure sustainable development (APFM, 2004).

23. 2.3 Impacts of land use on flood hazards
Hydrologic effects of urban development
Floods occur when large volumes of runoff flow quickly into streams and rivers. The peak
discharge of a flood is influenced by many factors, including the intensity and duration of storms
and snowmelt, the topography and geology of stream basins, vegetation, and the hydrologic
conditions preceding storm and snowmelt events.
Land use and other human activities also influence the peak discharge of floods by modifying
how rainfall and snowmelt are stored on and run off the land surface into streams.
In undeveloped areas such as forests and grasslands, rainfall and snowmelt collect and are stored
on vegetation, in the soil column, or in surface depressions. When this storage capacity is filled,
runoff flows slowly through soil as subsurface flow.
In contrast, urban areas, where much of the land surface is covered by roads and buildings, have
less capacity to store rainfall and snowmelt. Construction of roads and buildings often involves
removing vegetation, soil, and depressions from the land surface. The permeable soil is replaced
by impermeable surfaces such as roads, roofs, parking lots, and sidewalks that store little water,
reduce infiltration of water into the ground, and accelerate runoff to ditches and streams. Dense
networks of ditches and culverts in cities reduce the distance that runoff must travel overland or
through subsurface flow paths to reach streams and rivers. Once water enters a drainage network,
it flows faster than either overland or subsurface flow.
With less storage capacity for water in urban basins and more rapid runoff, urban streams rise
more quickly during storms and have higher peak discharge rates than do rural streams. In
addition, the total volume of water discharged during a flood tends to be larger for urban streams
than for rural streams.

24. 2.4 Land use planning and flood management
The need for a closer integration or coordination between flood management plans and land use
plans has been recognized since long. However, many countries are struggling to devise
appropriate policies and administrative mechanisms that would facilitate such integration.
Fundamental characteristics and the aims of those planning processes and policies have been
driven and implemented by different stakeholders and decision-makers. Therefore it is required to
seek a mutual understanding of those two processes.
2.4.1 Land use Planning
The field of public policy that is referred to as “Land use planning” in this paper has various
corresponding terms which are sometimes used interchangeably. Some of these are:
• Regional planning,
• Town and country planning,
• Urban planning, or
• Spatial planning.
Depending on the country and the context where the term is used the meaning of the term varies.
The overarching theme in all those terms, however, refers to ensuring that land is used in the
most efficient way to serve society in achieving its economic, social and environmental goals.
Usually this is undertaken in an environment of competing uses. As such land use planning is a
balancing act. With a reference to flood management that balancing act can be centrally
illustrated in the ongoing debate characterized by the two paradigms “space for development”
and “space for water/rivers”. The operational instrument to guide this process are land use plans.

25. 2.4.2 Flood Management
Similarly, various terms are used with reference to “flood management”. They differ in concept
depending on the country where they are used and the overall aim that is given to flood
management policy. For example, in some countries the term “flood management” is
synonymously used with “flood control”, emphasizing the control approach with connected focus
on river engineering and structural flood management measures. While those structural measures
also form part of flood management, the control approach is slowly loosing the central stage as
policy paradigm. Societies increasingly recognize that floods can only be controlled to a limited
extent and that absolute safety from flooding is a myth.
A sustainable development perspective has been brought into the flood management domain in
recent years leading to terms such as:
• Integrated Flood Management
• Sustainable or Holistic Flood Management
• Flood Risk Management
These approaches differ in subtle emphasis that is placed on the aims and objectives of flood
management, depending on the on the social and economic background of the area. For example,
Integrated Flood Management explicitly aims at maximizing the efficient use of floodplains
while minimizing losses of life from flooding (APFM, 2004). Flood risk management, while not
having a uniform definition in literature, lays emphasis on reducing the overall flood risk. In all
these environment.
Taking wider view on the interactions between the land and water environment within a river
basin, and on the wider socio-economic and environmental implications of floods, Integrated
Flood Management approaches form a good conceptual basis to bring about a convergence
between the land use planning process and the flood management process.

26. 2.5 Planning processes
2.5.1 Land use planning processes
Land use planning processes take place on various levels of Government, usually with increasing
levels of detail with decreasing administrative scale:
At the highest administrative levels such as federal or national level in form of land use policy or
(strategic) plans that specify general aims, objectives and measures for future land use that are
binding for all development authorities concerned.
At the state, district or similar level in form of plans specifying development ambitions and
required land uses under its jurisdiction.
At the local or municipal level in form of local land use plans with detailed allocations of
particular land parcels to specific uses or specific planning application procedures to be followed
for different zones.
On the local level those may be prepared as “comprehensive plans”7 to layout strategies to
manage land development in a community. Those plans are usually binding for the land owners
or developers concerned. Such comprehensive local development plans are for instance used in
various parts of the United States. Even though varying in emphasis in different locations such
plans would usually contain elements on community infrastructure (schools, hospitals, civil
defence, etc.) and transportation, housing and neighbourhood development, cultural heritage,
environmental assets and conservation sites, and economic development. They do have
sometimes a specific component on flood hazards and risks. An example of a land-use planning
map illustrating the distinctions of various land uses made is provided in the Annex.

27. 2.5.2 Flood management planning processes
Similarly flood management plans are developed at different levels as part of sectoral planning.
These include:
• Basin or Catchment Flood Management Strategy
• Basin or Catchment Flood Management Plan8
• Local Floodplain Management Plan
• Project Plan
The different plans largely vary on spatial and temporal scales. The first two are prepared for
comparably large areas and partly with substantial time horizons (reaching up to several
decades). The latter two types of flood management plans are prepared on rather small spatial
scales and time scales of months or a few years. Stand-alone local floodplain management plans
for a particular (relatively small scale) stretch along the river or all the floodplains under the local
government’s jurisdiction, are prepared, particularly in communities regularly affected by
flooding. In those plans a variety of specific issues can be addressed such as flood hazard
mapping needs, regulatory standards and procedures, areas where repeated flood losses have
occurred, areas which should be acquired by the public and cleared, local flood defence
requirements, river bed corrections and adjustments, etc.

28. 2.5.3 Other related planning processes
Depending on the stage of development in a society and its political priorities, various other
sectoral development plans may be of interest in flood management due to their relation to flood
risks:
Industrial Development: Flood risk consideration in planning industrial developments is essential
to provide sustainability to business operation and to control flood damages potential. These also
address control of pollution and spread of hazardous substances due to flooding of industrial
premises.
Agriculture Development/ Poverty Reduction: heavily relies on floodplain areas du to the readily
available fertile soil and water resources. At the same time agricultural practices can influence
runoff generation, infiltration processes and sediment yield.
Water Resources Management: flood risks form a central component of water resources
management plans to ensure the effective use of flood waters and safeguard the functioning of the
water system during floods.
Transport and Communication Development: location and structural design of those
infrastructure elements need to be planned in full awareness of flood hazard areas and the
possibility of hampering infrastructure impacting on the hydrological processes and flood
magnitudes.
Disaster Management: is undertaken with a view to all hazards affecting communities, including
flooding.
The complex inter-relation between various development processes to land-use planning and
flood management is illustrated by an example from England in Figure 3. A feature apparent from
this example is the obvious disparity between plans prepared for certain jurisdictions such as the
municipal or national level and those developed for catchments and river basins

29. 2.6 Roles of land use planning in flood management
strategies
47 It needs to be stressed that only a best mix of the strategies presented in Table 2 adjusted to the
particular circumstances of each river basin can serve the aims of Integrated Flood Management.
This becomes apparent when thinking of a flood management strategy that would only focus on
reducing the susceptibility to damage as this would lead in its most consequent form to largely
ignoring the development potential of the floodplains.
Strategies and Options for Flood Management

30. Taking a closer look at the strategies and options for flood management it becomes apparent that
land use planning plays a central role in three out of four of them, which in the following is
elaborated further.
2.6.1 Reducing Flooding
49 All structural flood management interventions need to be incorporated into the land use
planning process to safeguard spatial requirements of those measures now and in the future. This
proves in practice a challenging task as spatial requirements can be substantial with limited
available land resources e.g. for a dam or reservoir but similarly for levees and diversion
channels. Further our knowledge of the future is inherently limited. This particularly concerns
future economic drivers, as well as future rainfall patterns and other climatic factors which form
the basis of planning the location and spatial requirements of hydraulic works in general and
structural flood management measures in particular.
50 Another option under this strategy summarized under “Catchment Management” refers to
measures taken over the whole catchment area (not only the water system) to optimize the
functioning of the catchment, in this instance for flood management. This can entail a source
control approach that seeks to keep as much rainwater retained where it falls so flood peaks can
be attenuated. Another consideration taken in Catchment Management refers to where flooding
causes least harm - and where it should occur - to protect other crucial areas such as cities and
industrial centers with high potential for damage. Those high risk areas need to be identified and
made part of the land-use planning and regulation process, in order to be kept free from high risk
uses.

31. 2.6.2 Reducing Susceptibility to Damage
51 This strategy has one of the strongest relations to land use planning and regulation. A basic
requirement is the availability of flood hazard maps that indicate the areas exposed to flooding
for flood events of a given return period. Based on those maps different flood hazard zones can
be delineated and placed under land-use regulation to limit the flood damage potential in those
areas. Those regulations are tools to prescribe what uses are possible and under which conditions.
Such conditions can also be put in place in terms of building regulations and codes. Further they
can be used to prescribe adjustments to existing developments in those areas, e.g. flood proofing
or relocation of existing developments.
2.6.3 Preserving the Natural Resources of Flood Plains
52 Floodplains are subject to competing uses. Societies have an interest to make use of their vast
natural resources which in certain cases leads to an overexploitation in form of converting large
parts of natural habitats on flood plains into other land-forms with known repercussion not only
for biodiversity and the functioning of floodplain and riverine ecosystems but also for associated
livelihoods and the economy. Land use planning and regulation plays a key role in balancing the
development requirements and the preservation of the natural resources on flood plains.

32. 2.7 Land Use Implementation Tools
Flood risk–based land use plans give communities an overview of which areas need to be
protected, evacuated, developed, or redeveloped. These plans need to be accompanied by
implementation tools that are acceptable to the community and that can be enforced with local
capacity and resources. Such tools can be regulator , economic, financial, or behavioral. They are
summarized in table 1 and described in more detail below.

33. 2.7.1 Regulatory Instruments
Regulatory instruments—such as zoning plans, development controls, and building codes—
prevent chronic disaster risk in the siting and construction of new settlements and reduce disaster
risk in vulnerable existing settlements.
Over the last decade, countries with mature building code systems experienced 47 percent of
disasters globally, yet accounted for only 7 percent of disaster fatalities (GFDRR 2015). Risk-
based regulations not only are crucial in reducing disaster risks; they also have proven to be cost-
effective.
1. Zoning plans demarcate areas by degree of flood risk and link them to appropriate, safe, and
permissible land uses. Land use regulations and development controls determine appropriate land
uses and guide neighborhood design for different flood risk zones.
2. Development controls designed to manage flood risk ,must establish development patterns
that accommodate water storage, conveyance, and drainage, such as rainwater harvesting
mandates, storm water ordinances, and green-gray infrastructure requirements. Development
controls may (i) limit land use in floodway zones, (ii) allow multiple uses with elevated or flood-
proofed structures, (iii) require setback from hazard, and (iv) regulate impervious surfaces. Zones
where land use changes can significantly increase flood risk downstream can also be regulated to
strengthen retention.
3. Building codes specify minimum design standards for materials, access points, and floor
levels for development within a designated zone. Building codes to accommodate flood incidence
and reduce flood losses may specify (i) elevated siting and roads, (ii) compulsory retrofitting of
flood protection measures, (iii) flood proofing for critical buildings such as hospitals and
emergency shelters, and (iv) planning and design for redundancy. Building codes can also specify
building orientation to minimize disruption of flood flows and require emergency exits in an
elevated area such as the roof (WMO 2016).

34. 2.7.2 Financial Instruments
Through its investment choices—whether transport, housing, or infrastructure—a municipality
can orient land use. Public investments can discourage occupation of high-risk areas not by
prohibiting their development, but by making other areas more attractive. Financial instruments
include public funds such as national transfers, donor assistance, municipal bonds, and flood loss
aid linked to property taxation, recovery funds, and reinsurance; they also include public-private
partnerships and flood insurance at individual, local, and national levels.
2.7.3 Economic Instruments
Economic instruments are financial rewards, incentives, and penalties that encourage behavior
changes in businesses, households, and individuals. Cities are increasingly exploring the use of
such instruments, particularly economic incentives, to implement land use plans. Using these
incentives not only supplements public funds, it also encourages private developers and
communities to accept and comply with flood risk–based land use plans. Economic instruments
rely on market information that might not be easily accessible, and on the capacity of agents for
acting rationally in economic terms. A range of economic instruments is available to cities,
including preferential taxation, tax credits, conditional insurance, and conditional permitting.
Land-based financing (density transfer or density bonus) is another important instrument that has
been used to manage urban growth in several countries with different resources, technical
capacities, and governance systems. This instrument uses land-value capture mechanisms, such as
land readjustment (LR) and transfer of development rights (TDR), which are often complex to
design and implement, especially where land management capacity is poor. Local governments
can improve existing land management capacity by combining LR and TDR with other municipal
tools, and by strengthening municipal capacity in land administration to work with real estate
markets.

35. 2.7.4 Behavioral Instruments
Behavioral instruments are important for land use policies as a way to encourage co-investment
between public, private, and nonprofit sectors, and to incentivize useful behaviors and discourage
risky ones.
Land use policy that distributes and shares risk among multiple city stakeholders helps
institutionalize resilience by integrating it into the planning and policy of various sectors across
the city.
Risk communication is essential for management of risk. Awareness is the first step for
developing safe practices on land use, and any plan should include a communication strategy.
Behavioral instruments include (i) awareness campaigns that use indicators to monitor and
inform the public and foster stakeholder consensus; (ii) mandatory disclosure in real estate
transactions; (iii) warning systems, including institutional coordination for emergency warning
and management; and (iv) capacity building (e.g., training of communities and schools;
simulation exercises), which should be based on the policy at issue, the specific stakeholders, and
hazard, risk, and vulnerability assessments, as well as on lessons learned from previous disaster
events.

36. 2.7 Tools and mechanisms for interaction
Interactions between those planning processes can take place at various levels and through a
number of instruments, which are subsequently discussed. It needs to be noted that the
application of those instruments depends on the place flood risks have on the prevailing political
agenda. Generally, development planning plays politically a much more important role and the local and
regional development agencies usually hold far more powers over development than dedicated
flood management agencies. Examples do also exist where river basin authorities are mandated to
formulate and execute development plans or flood risk management plans, but those cases are
rather the exception than the rule9. Only after exceptionally large floods or after flood disasters,
flood management issues acquire (temporarily) importance on the political agenda.

37. 2.7.2 Flood risk assessment of strategies and plans
55 Strategic plans in particular on higher administrative levels and outside the flood management
domain can be placed under flood risk assessment procedures. This would help to gauge in
advance the likely impact of a particular plan or strategy.
2.7.3 Flood risk assessment for particular planning applications
56 Obligations can be placed on developers of particular land parcels in flood hazard areas to
provide flood risk assessments as part of planning applications together with required flood risk
reduction measures.
2.7.1 Flood hazard maps
Provided by a qualified scientific technical institution on appropriate scales, flood hazard maps
are the central instrument to facilitate interaction between different sectoral planning agencies.
Obligations can be placed on those agencies that they must consult those maps or the agency that
provide them in taking planning decisions.
Comparison between a flood hazard map and a flood situation
during the 2005 floods in Sarnen, Switzerland

38. 2.7.4 Environmental Assessment
Two environmental assessment procedures applied for various instances can also incorporate
elements of flood risk. One is Strategic Environmental Assessment conducted for plans and
programs with likely significant effects on the environment and the other is Environmental
Impact Assessment applied on project scales.10
In assessing the level of opportunity that could arise from interaction of planning processes it is
important to bear in mind that a dedicated sectoral authority, Through this multi-objective
planning requirement, the hazard consideration will be one of many considerations taken in
preparing local land use plans.
Another consideration is required about the local constraints in terms of financial means, limited
jurisdiction and technical expertise available at the local level. Local economic growth and
development is one key to develop the supply side of finances available to local government. The
return received from activities in these areas is usually perceived as direct while investments in
hazard mitigation of whatever kind may be perceived as less visible, potentially slowing
immediate growth targets in particular when employing land-use regulations and therefore
secondary priority to local decision making.
In view of this a collaborative approach between sectoral planning agencies, specialized technical
agencies and local governments is required that would seek to complement each others
jurisdictional, technical and financial means in maximizing the efficient use of floodplain
resources.

39. 4. DEVELOPMENT MANAGEMENT
TECHNIQUES IN THE FLOOD
HAZARD CONTEXT

40. 4.1 Paths of Government intervention
To implement a land use plan Governmental action can use various means. The first and perhaps
most applied is land-use regulation which in practice is usually combined with other means such
as the provision of incentives, knowledge enhancement and redirecting or rearranging public
investment. The typology provided in Table illustrates those means in more detail with a
particular view to the flood hazard context.

42. 5. LEGALAND INSTITUTIONAL
FRAMEWORK

43. 5.1 Rights, Powers and Obligations
Obligation of the State to provide flood hazard or risk maps as the basis of planning
The very basis of incorporating flood risk in development planning is the availability of fairly
accurate information on flood hazards in form of flood maps. To keep technical and scientific
standards harmonized and in view of the highly specialized nature of the subject, it seems
reasonable to argue that the preparation of these maps should be coordinated on a higher
administrative level, i.e. the river basin or the federal level. Obligations must be placed on
relevant agencies to prepare such maps by law backed up with required resources, to make them
publicly available and update them in adequate intervals. A recent example is the “EU Directive
on the Assessment and Management of Flood Risks” which mandates Member States of the EU
among others to prepare flood hazard maps and flood risk maps, at the most appropriate scale.
Provision that natural hazards must be taken into account in the land planning process
92 Once adequate information is made available provisions should be incorporated in the relevant
laws and regulations that the hazard information must be taken into account as part of the land
use planning process. The (technical) agency responsible for flood mapping should be placed in a
position where it needs to be consulted on strategic plans and on specific development planning
applications as required23.
Obligation to disclose hazard information in land transaction
93 Given adequate flood hazard and risk maps are available, sellers of property can be obliged by
law to disclose information about prevailing hazards to buyers of the property. Failure to comply
can result in legal claims for compensation.

44. 5.2 Clear definition of roles and responsibilities
94 The roles which the different actors take in planning and flood management largely vary from
country to country, between sectors, administrative scales and the private public domain. In one
country provision for flood defences may exclusively rest with regional catchment authorities or
similar body, while in others those responsibilities are shared between actors on different scales
from federal government down to the individual property owner or developer. Those roles must
be clarified and defined by law. This is essential to minimize conflicting or overlapping
responsibilities and to give clear mandates to specific organizations to undertake certain tasks
combined with the provision of resources to undertake those tasks. A separate Tool, the ‘Rapid
Legal Assessment Tool’, provides assistance in undertaking an initial assessment of the prevailing
legal system and the roles that different actors take and gives guidance as to how gaps can be
identified for the flood management sector.24
5.3 Institutional Coordination Mechanism
95 For land use panning to fully utilize its potential in flood management there is need for
adequate coordination mechanisms between different sectoral planning agencies on the one hand
and land use planning undertaken at the local or regional level on the other hand. Even though
this requirement for horizontal and vertical integration in the flood risk management
context have been voiced over decades in different forms, there are indications that in
practice the integration of land-use planning and flood risk management has not been
taken up in many places yet.25

45. 5.4 Compliance and enforcement
96 To enforce existing land-use regulations, the administrator of a floodplain or local
authority requires a series of legal powers. Land-use regulations or zoning ordinances
usually provide such powers to administrators using various means of enforcement.
Depending on the applicable laws and regulations an administrator may obtain legal
powers, for instance:
To take remedial action as necessary to prevent damage to property or danger to life
To negotiate a schedule for the completion of the construction, repairs or other activity
necessary to abate the violation;
To initiate a civil or criminal complaint against the violator;
To use work forces or contract to perform the required remedial actions, and submit an
invoice to the person for payment;
To initiate a procedure resulting in denial of flood insurance due to the violation of
existing laws and regulations.

47. 6. CONCLUSIONS AND RECOMMENDATIONS
The need to integrate flood risk in land use planning is immense, given the frequency,
severity, and impacts of floods in recent decades. Land use planning that incorporates flood
risk information and integrates ecosystem- based measures can be cost-effective. In turn, land use
planning can be integrated in all stages of a flood risk management plan—from prevention and
response to reconstruction—along with other measures, both structural and nonstructural. An
understanding of flood risk should inform community priorities and decisions in all stages
of the land use planning process. A set of land use instruments must be selected that addresses
the type of local flood risk, that is acceptable to the community, and that can be implemented
with local resources and technical capacity. Land use plans that address flood risk must be
integrated within multiple sectors and at multiple scales: local area plans, city strategic plans,
metropolitan visions, and watershed and national policies. This type of integration involves
multiple public sector actors (city governments, public sector companies including utilities, and
meteorological and planning institutions) as well as actors from civil society, educational
institutions, research centers, and the private sector— and all must be coordinated to ensure they
work effectively. Planning, implementation, and enforcement of risk-based land use plans
face challenges in both developed and developing countries. Where cities have succeeded, it
has primarily been due to political will and citizen engagement, very often in the wake of a recent
flood disaster. Once the leadership and the community take a proactive stance, they can work
together to resolve challenges such as finance, technical capacity, land ownership, coordination,
and enforcement. Ultimately, successful land use planning for flood risk management requires
investment in two areas: (i) educating decision makers and communities about the role of land
use planning in managing flood risks, and (ii) building sufficient technical and governance
capacity to formulate, implement, and manage a flood risk–based land use planning process.

48. When decision makers appreciate the benefits of land use planning as a flood management tool,
they will be better able to act on the following recommendations:
• Help communities understand their flood risk so that they demand safe and sustainable urban
development from decision makers and professionals. • Create a common goal and foster
proactive collaborations between all stakeholders (government officials, civil society,
communities, the private sector) and initiate institutional coordination among different sectoral
agencies and levels of government. • Establish land use planning as a cost-effective measure to
manage flood risks by adopting a green infrastructure approach. • Foster partnerships and
networks to (i) advance multidisciplinary research (combining science, policy, and practice); (ii)
share innovative practices in legislation, policy, stakeholder coordination, and land use
regulations and incentives; and (iii) develop standards and identify research and capacity gaps. •
Promote community engagement and participation so that risk assessment and land use planning
respond to local needs and reflect local cultures. Engaging the community in preparing a risk-
sensitive land use plan is crucial to its acceptance, implementation, and updating.
When stakeholders have sufficient technical and governance capacity, they will be
better able to act on the following recommendations: • Draw on technical
innovations—in information technology and geographic information systems— to ensure
that flood risk data and real-time land use information are most effectively managed and
used. • Train city officials so they appreciate flood risk management as an integral
component of a multihazard approach that will help the community reach its sustainable
development goals, and so they can lead policy and administrative reforms for land use
planning. Peer networks and e-learning platforms are useful training tools and can foster
dialogue between large numbers of decision makers and professionals.

49. • Develop locally appropriate standards for land use regulations, engineering design,
construction of various infrastructures, and guidelines and methodologies for retrofitting
of structures. Flood risk standards must also be aligned with existing professional urban
planning standards. To encourage compliance, building codes need to be stratified and
accommodate the range of construction types, from sophisticated engineered buildings
to non-engineered buildings built by petty contractors. Compliance is more likely where
permitting processes are efficient, risk information is available and shared, building
practitioners are certified, private third parties are accredited to provide review and
inspection, and insurance mechanisms are used to augment building control. • Create a
pool of professionals who understand how to use risk information and work with the
community to achieve socioeconomic and resilience goals through the land use planning
process. Professional associations and planning schools should update professional
responsibilities and curricula to integrate risk guidance. Since land use challenges and
institutional capacities vary by location, generic and prescriptive land use processes are
not advisable. While the experience of other cities can be informative, each locale must
assess its specific conditions and develop customized solutions. Apart from taking local
technical and financial capacities into account, land use solutions must also be
cognizant of local planning approaches and land tenure regimes.