Flood Risk Assessment Intervention To Town Planning Scheme
Flood Risk Assessment Intervention To Town Planning Scheme
Flood Risk Assessment Intervention To Town Planning Scheme
CONTENTS
Chapter: 1.0 INTRODUCTION.................................................................................................................................. - 1 -
1.1 INTRODUCTION.............................................................................................................................................................. - 2 -
2.1 GENERAL........................................................................................................................................................................ - 7 -
3.1 INTRODUCTION............................................................................................................................................................ - 29 -
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4.1 OVERVIEW..................................................................................................................................................................... - 40 -
4.1.1 Background............................................................................................................................................................ - 40 -
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5.1 GENERAL...................................................................................................................................................................... - 84 -
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CONCLUSION....................................................................................................................................................... - 152 -
REFERENCES......................................................................................................................................................... - 153 -
APPENDIX............................................................................................................................................................ - 157 -
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LIST OF FIGURES
Figure 1Risk conceptualization................................................................................................................................- 8 -
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LIST OF TABLES
Table 1 Spatial Dimensions of land use effects.......................................................................................................- 32 -
Table 3 Population and Sex Ratios: in comparison with other urban agglomerations in the State............................- 48 -
Table 5 Yearwise Max. reservoir’s Water Levels and Annual Max. Release from Spillways.......................................- 56 -
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Table 15 Relief....................................................................................................................................................... - 79 -
Table 16 Engineering............................................................................................................................................. - 80 -
Table 26 Typology of development management techniques in the flood hazard context.....................................- 140 -
LIST OF CHARTS
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LIST OF MAPS
Map 1 Study Area Map (T.P. Scheme 23).................................................................................................................- 91 -
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1.1 INTRODUCTION
With the rapid urbanization as well as industrialization, the climatic condition of the earth is changing and with this
change, the number of occurrence of natural hazards is also increasing. India, having considerable large land parcel
with long coastline as well as mountain ranges is highly vulnerable to a variety of hazards. With considerably
increasing urbanization in the country, the construction activities are flourishing. Any natural hazard in vicinity of
these urban centers can become a disaster if the urbanization has taken place without having interventions of
hazards and risk elements thereof. In Gujarat state the Gujarat Town Planning and Urban Development Act, 1979 is
used for planning and development of urban centers by means of authorities. This act has provision for planning of
urban areas through a mechanism of Town Planning Schemes wherein certain planning aspects are well defined.
Planning of a T. P. Scheme through the act provides detailed preparation based on a fixed land use pattern. If the
hazard and risk level of a particular area under development is known to the authority, the element can be useful
for broad planning of the area in a way that the development in future is less vulnerable to hazards. With recent
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physical expansion of Surat city, proper planning is required for newly included areas. The planning shall be done
using T. P. Scheme mechanism as per prevailing practice in the city at present. Prior to suggest modifications in
planning of raw lands, it is very essential to analyze the developed areas and certain set of indicators shall be
prepared so as to safe guard the future development from frequently observed hazards.
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Present study shall be a humble attempt to analyze current development based on past planning efforts from flood
risk vulnerability point of view. Justification of the topic with aim, objectives, scope of work and approach is
following in the subsequent sections of the chapter.
Surat city is observing remarkable growth and urbanization. From merely 2, 23,182 persons in 1951 it has reached
to a population of 24,33,785 persons in 2001 with countrywide highest decadal growth rate in the last decade.
Being economic hub of Gujarat state, it is having unique identity with variety of activities. The city has considerable
exports of goods across the globe. Such a way the city is having national importance and it is very much essential to
safe guard the city from ill effects of natural hazards. For the purpose, a proactive approach is very much needed in
terms of risk interventions in planning at early stage. The city is highly prone to floods as it has developed on the
banks of a perennial River Tapi. Citywide flooding situations are observed frequently and since a decade it has been
detected that a major flood has a return period of 4 years. Based on hazard calendar for Surat city floods are likely
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to occur between Junes to Septembers whereas earthquakes are likely to occur anytime throughout a year.
Being a city of national importance, it is very essential to apply proactive planning approach through T. P. Schemes
to reduce the earthquake as well as flood risk vulnerabilities of Surat city. Present study is on risk assessment of
planed T. P. Schemes for these two hazards in particular and to prepare a checklist for future planning. A uniquely
developed Rapid Visual Screening (R.V.S.) survey technique shall be used to identify Flood vulnerable areas in
existing T. P. Schemes. Flood vulnerability of schemes under study shall be obtained based on past observed flood
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levels in particular areas under examination. An attempt shall be made to identify parameters needed to be taken
care of while preparing a T. P. Scheme and factors to be included in the General Development Control Regulation
prevailing in the city. Such an approach for risk assessment may be applied proactively for risk element intervention
to planning of town planning schemes in future.
To develop a unique and proactive approach with reduced risk vulnerability to floods while planning for future
development of urban areas of a city is the aim of this study.
For developing a unique planning approach, following is the set of objectives which shall be performed to achieve
the desired aim.
1) To review the prevailing planning approach and level of hazard risk vulnerability
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As Surat city has a wide physical spread in terms of spatial area, the scope of study shall be limited to an existing
T.P. Schemes. Also, the study shall be having scope for vulnerability assessment of flood hazard only. Flood
vulnerability assessment shall be based on available data and observations.
STEP : 1 General Study of National and International literatures regarding Basic terminologies, Impact of flood in
urban areas, Flood Risk assessment techniques and land use planning etc.
STEP : 2 Identifying the Study area based on Location, Contour map of area and, past flood water position in and
surrounding vicinity.
STEP : 4 After analyzing the Data vulnerability maps is to be prepared and identifying the vulnerable areas.
STEP : 5 Based on findings, suggestions and recommendations regarding land use planning is to be given.
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2.1 GENERAL
Disaster[9] is the tragedy of a natural or human-made hazard (a hazard is a situation which poses a level of threat to
life, health, property, or environment) that negatively affects society or environment. In contemporary academia,
disasters are seen as the consequence of inappropriately managed risk. These risks are the product of hazards and
vulnerability. Hazards that strike in areas with low vulnerability are not considered a disaster, as is the case in
uninhabited regions. A disaster can be defined as any tragic event with great loss stemming from events such
as earthquakes, floods, catastrophic accidents, fires, or explosions.
The studies reflect that all disasters can be seen as being human-made, their reasoning being that human actions
before the strike of the hazard can prevent it developing into a disaster. It is not always right. Sometimes the impact
of a particular hazard increase due to sequential natural disasters. A classic example is an earthquake that causes
a tsunami, resulting in coastal flood. So, Hazards are routinely divided into natural and human-made. A natural
disaster is a consequence when a natural hazard (e.g., volcanic eruption or earthquake) affects humans.
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The American Planning Association[10] defines a hazard as "an event or physical condition that has the potential to
cause fatalities, injuries, property damage, infrastructure damage, agricultural loss, damage to the environment,
interruption of business, or other types of harm or loss." Hazard identification is defined as "the process of defining
and describing a hazard, including its physical characteristics, magnitude and severity, probability and frequency,
causative factors, and locations or areas affected." 1 Finally, a flood hazard[10] is the potential for inundation that
involves risk to life, health, property, and natural floodplain resources and functions. It is comprised of three
elements: severity (magnitude, duration, and extent of flooding), probability of occurrence, and speed of onset of
flooding.
The risk situation is quite complex to define. In fact, we assume that we can analyze it from two independent
factors, one based on the socio-economic perception of risk, which is called vulnerability and the other depending
on the hydrology and hydraulic knowledge of the hydrological regime, called Hazard [24] as shown in figure. The first
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factor is called vulnerability[24] and represents the sensitivity of land use to the flood phenomenon. Consequently, it
depends only on the type of land use and the social perception of risk. The second factor is called hazard and
depends only on the flow regime of the river, independent of the land use of the flood plain.
There is nothing that can be done to prevent the occurrence of natural disasters. Disasters will continue to result in
losses of lives, destruction to property and the disruption of the social and economic fabric of entire communities.
The losses will continue to increase because of population growth in vulnerable areas, such as coastal regions, flood
plains, and seismically active zones. But while disasters cannot be prevented, their impact on loss of life and
property can be drastically reduced with proper risk assessment and planning.
There is a relationship between exposure to a flood hazard, risk and vulnerability. Vulnerability is the measure of
the capacity to weather, resist, or recover from the impacts of a hazard in the long term as well as the short term.
Vulnerability depends upon many factors such as land use, extent and type of construction, contents and use, the
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nature of populations (mobility, age, health), and warning of an impending hazardous event and willingness and
ability to take responsive actions. This means that within an identified flood hazard area there may be the same
exposure or risk of flooding, but a wide range of vulnerability to the hazard. Floodplain managers and programs
need to recognize and account for ranges of vulnerability to flood hazards.
The occupancy or use of flood-prone areas involves a degree of risk. Risk is exposure to an undesired event. It can
be expressed in probability that the event will happen, often during a calendar year. Probability [10] is a numerical
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index of risk; it is a measure of the likelihood that the undesirable event will occur. If the event is sure to occur, the
probability is 1.0; if it cannot occur, the probability is Calculated risk is basic to the occupancy and use of flood-
prone areas. How much risk are we willing to assume? Decisions may be based on a certain flood event or risk. The
key is how much risk and to whom and how will they be affected. To overcome from all these things, the answer is
to work on flood risk assessment.
The different sources of information[10] for assessment of flood risk are as follows.
Physical and geomorphic techniques, e.g., look at boulders along streams, water transported debris along
walls of canyons
Regional information, i.e., look at flood occurrences along similar streams in the area
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Any floodplain management program must be established on a sound technical and scientific basis in order to be
effective, whether for flood loss reduction or to manage natural resources, or both. For management purposes,
nature of the flood hazard and the degree of flood risk for a specific site often has to be determined.
An urban flood risk management plan[23] has to start with the assessment of present and future flood risks (fig-1).
For that, clear understanding and distinction between the three components that create risk - hazard, exposure and
vulnerability - provides the necessary information for factoring in most flood related aspects in the overall
management of risks and at the same time contribute substantially to the development and well being of the
society.
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The composition of risk, as analyzed from risk assessment exercise[23] can help address not only the efforts
towards flood risk management but also in improving the well being of people, particularly if the analysis points
toward need to build resilience in the effected population.
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Many parts of India are vulnerable to flood hazard. According to the estimates prepared by the Rashtriya Barh Ayog
(National Commission on Floods)[25], the area prone to floods in the country is of the order of 40 million hectares.
During such floods, the losses suffered by the people include: the damage to crops, damage to houses and loss of
human and cattle lives. Besides, public utilities also get damaged on a large scale. Most of the lives lost were due to
drowning of people due to the collapse of their shelters which also results in the displacement of the people from
their habitations for considerable length of time, putting a huge burden on the relief machinery of the States to take
care of their temporary sheltering and feeding requirements.
Now if we talk about the Surat city than, Surat[15] city (India) situated at the tail end of river Tapi is subjected to
moderate to heavy floods frequently due to heavy rainfall in the catchment area. Study of floods at Surat city has
been made in this paper. To minimize the effect of flood at Surat city, certain preventative measures like De-silting
from reservoir, Increasing the carrying capacity of river Tapi, Storm Water Drainage Line Parallel to river,
Construction of flood protection wall, Recharge of groundwater, Spreading of flood water on saline Soil etc. have
been suggested. They have also suggest the Hi – tech disaster management which includes the Preparation of
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counter map for the area from Ukai to Sultanabad including Surat city using GPS technique, Preparation of map
showing markings of H.F.L as well as their reference, Reference map (co-ordinate) of place should be with rescue
and relief team, so that if flood occurs, relief work can be done effectively and efficiently by boat, helicopter etc.
Due to the geographical importance of the Tapi basin, the aspects of diversion of flood water to other rivers like
Purna river near Navsari, Mindhola river near Sachin, Kim river near Kosamba, Sena creek near Dandi, Olpad, Tena
creek near KRIBHCO will work to protect the life of surat city. Surat, the city chosen by Rockefeller Foundation [14] as
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one of the centers for climate change studies, has now come up with a website dedicated to spreading awareness
about the climate changes in the region. The creation of the website is also a part measuring the impact of climate
change in region which will be updated with every new finding.
Inappropriate development within flood plains can lead to an increase in flood risk, both to the proposed
development and to existing developments up and down stream of the proposed development. Mr. James[12]
describes the processes that should be followed when assessing the potential impact of a new development on
flood risk.
An urban flood risk management plan has to start with the assessment of present and future flood risks. For that,
clear understanding and distinction between the three components that create risk - hazard, exposure and
vulnerability. Risk assessment has to be carried out in an integrated manner, i.e. identifying all the possible water
related hazards, including how they are likely to develop in the future as a consequence of urbanization or other
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development activities. To be useful in land-use planning the risk assessment shall be carried out within a multi-
hazard concept. Such an assessment should give information about the probability of a hazard’s occurrence and the
respective potential of loss. The composition of risk, as analyzed from risk assessment exercise can help address
not only the efforts towards flood risk management but also in improving the well being of people, particularly if
the analysis points toward need to build resilience in the effected population.
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Floods are a consequence of natural hydro-meteorological phenomenon, combined with their interaction with the
catchment characteristics. Through interventions in changing the characteristics of the catchment the run-off
processes can be altered, thereby making it possible to reduce the magnitude of the flood hazard thus generated.
Mr. James[12] had identified the different sources of flooding like Coastal flooding, Fluvial flooding, Sewer flooding,
Overland flow flooding, Groundwater, Infrastructure failure etc as an approach to proceed for the flood risk
assessment. Then, he had scale up the areas which are under the flood risk. Flood risk assessment for newly
developed area is play very important role as to know whether the development affects the flood frequency or not.
For taking mitigate action one has to identify the potential impacts of new developments on flood risk. According to
him, an effective action is to design the development such that vulnerable developments are located outside of the
floodplain altogether. If the development could lead to a significant loss in floodplain storage then compensatory
floodplain storage works should be designed to ensure that no net loss of floodplain storage occurs due to a
development. New developments may increase flood risk in a number of ways, but use of appropriate scientific
tools to aid planning and design of development sites may enable the engineer to avoid unacceptable increases in
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flood risk. This paper provides a brief overview of the flood risk assessment process.
According to the report, written and published by Ashford Borough Council and the Environment Agency, Regulation
27 in the year 2009 regarding flood risk assessment, The Environment Agency should produced Flood Zone Maps
identifying areas considered to be at High, Medium and Low probability flood risk in accordance with ‘Development
and flood risk’ definitions. Certain highly or more vulnerable uses such as housing and residential institutions,
health and education buildings, emergency services and essential infrastructure should not normally take place in
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areas at high probability of flooding (i.e. within the 1 in 100 year river floodplain). By applying the sequential
approach for new development, the Core Strategy has generally avoided areas of high probability of flood risk and
the functional flood plain. For any coastal city, Area action plan in regard with flood risk probability had been
prepared. The future development should be carry out based on this AAP. Means the allotment of the land should
be in such a way that community can survive from heavy flood. Some sites in the AAP area contain land in two or
more Flood Zones. In these locations it is expected that a sequential test will be applied at a site level to ensure that
the more vulnerable uses are located on the lowest Flood Zones. In practical terms, appropriate mitigation measures
must be put in place and, furthermore, it is likely that appropriate compensatory replacement floodplain storage will
be required or other suitable flood risk management measures employed to ensure risk to others is not increased.
Mr. Errol Douglas[17] working in water resources authority in Jamaica city had publish one paper regarding flood
hazard management, mapping and early warning systems in Jamaica city. They have prepared the Flood plain
mapping plan. The development in the city is going on based on this plan means where to locate which type of
buildings based on their priorities. The basic services like Hospitals, Fire stations, schools etc. located in low
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flooding area. They always are in touch with the people who are living in these types of vulnerable areas. They
always consider relocating the people at safe place to save the lives, Just like slum relocation program in India.
Design and location of the Infrastructural facilities are also finalized in such a way that it would not obstruct the
flood plain area of the city.
Orbital remote sensing [18] is now poised to make three fundamental contributions towards reducing the detrimental
effects of extreme floods. Effective Flood warning requires frequent (near-daily) radar observation of the Earth's
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surface through cloud cover. In contrast, both optical and radar wavelengths will increasingly be used for disaster
assessment and hazard reduction. These latter tasks are accomplished, in part, by accurate mapping of flooded
lands and commonly over periods of several days or more. We use radar scatterometer data from QuikSCAT to
detect changes in surface water area and with a full global coverage every 2.5 days. Also, MODIS, RADARSAT, and
other higher spatial resolution data are used for flood mapping and other flood measurements.
[18]
According to Mr. Robert , Floods are transient surface events and can occur at the same time over widely
separated geographical locations (even on different continents). To record such events, timely information with
frequent and large-area coverage is necessary. If the in-situ instrumental data is not proper than at the time of high
flood event many gauging stations can be destroyed and it will takes several years to repair it. Flood detection task
depended on the availability of clear-sky optical data, much of which was processed long after the actual flooding.
The first area of work, detection of new flood events and public warnings thereof, is still experimental but is making
rapid progress. Radar sensors are preferred due to their cloud penetrating capability. Relatively low spatial
resolution, but wide-area and frequent coverage, are appropriate: the objective is to locate where within a region or
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watershed flooding is occurring, and not to map the actual areas that are inundated. The second area, rapid-
response flood mapping and measurement, provides information useful for disaster assessment, and has become a
relatively common activity. A wide variety of sensors have been used. However, the capabilities are still relatively
immature, and there is much potential for development of advanced measurement capabilities that can better
define flood severity and damage. Finally, the third area of work, flood hazard mapping, is based on the recognition
that not only can floods be imaged and mapped as they occur, but these records of extreme events can and must
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also be preserved in archival form. In this way, maps of lands actually flooded complement maps of land areas
predicted via modeling approaches to be subject to flooding.
According to Mr. George P. C. [20] A good starting point in assessing the vulnerability of a given region should be the
identification of potential disasters, the establishment of a historical database of past events, the delineation of the
geographical distribution of potential maximum disaster impacts, and the preparation of a plan to mitigate adverse
effects and protect life and property. Apart from all other disasters, for flood it is important to prepare the historical
database with its recurrence frequency for the assessment. Assuming that the historic record is long enough and
there have been many years of direct observations, it is possible to establish approximately when a disaster may be
expected again. However, if the historic record is limited, statistical methods are of no use. For more accuracy, a
model study is also being a useful option. Physical models are expensive to construct and difficult to scale down in
size both geometrically and kinematically. However, physical models have been very useful in assessing the risks
and effects of different types of disasters. Computer models using correct input parameters permit relatively
accurate predictions of potential disaster effects and can be invaluable in risk assessment studies.
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Having completed the preliminary stages, The analysis must be simplified further into forms that can be understood
easily by the general public. Thus, the final product of historical, statistical or modeling studies must indicate the
spatial variations of the hazard risk in the form of maps. Maps can be prepared for all natural hazards that may
impact a geographical region. But it should be with minimum variation and acceptability risk. The best way to
improve the accuracy is to prepare a micro-zonation of disaster risk.Another Important as well as effective
technique is developed by the Crawley Borough Council in the year 2007 named as Strategic Flood Risk Assessment
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(SFRA). Strategic Flood Risk Assessment (SFRA)[21] has been carried out to collate all known sources of flooding,
including river, surface water (local drainage), sewers and groundwater, that may affect existing and/or future
development within the city; to delineate areas that have a ‘low’, ‘medium’ and ‘high’ probability of flooding within
the city; to recommend appropriate land uses that will not unduly place people or property at risk of flooding and
Where flood risk has been identified as a potential constraint to future development, recommend possible flood
mitigation solutions that may be integrated into the design (by the developer) to minimize the risk to property and
[21]
life. The Crawley Borough council has prepared the planning policy statement 25 (PPS25) with respect to
development and flood risk. The main aim of this PPS25 is to ensure that flood risk is taken into account at all
stages of the planning process in order to prevent inappropriate development in ‘at risk’ areas. They have prepared
this Strategic Flood Risk Assessment tool for finding out whether the future development is carried out on safe zone
concerning flood or not. A person who wants to carry out any type of development work, he has to pass a
sequential test for his project. A summary of the adopted SFRA process is provided in the figure below, outlining
the specific tasks undertaken and the corresponding structure of the SFRA report.
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[16]
The main objective of London Flood Strategic Response Plan is to ensure a coordinated response to a flood,
which will protect life and well-being with the mitigation of property and environmental damage as a strong
supporting objective. The primary focus is on both tidal flooding from the River Thames and on fluvial flooding
from the tributaries that flow into the River Thames in London. The procedures apply also to surface water flooding
resulting from excessive rainfall, although some responsibilities will be different for this circumstance. Have great
potential and are highly necessary, however work best when implemented in a framework (SEF) where synergies are
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utilized e.g. multipurpose use of land as defense, recreational and ecological site. The failure modes of
embankments are complex and highly variable. Locally failure was largely due to seepage/breach through erosion.
Models/ fragility curves should produced for existing sites and new embankments constructed with the optimal
geometry, foundation and materials. The notion of “unacceptable risk” is a judgment often distorted in periods of
financial difficulty and often climatic uncertainty can dissuade investment. The EA should plan significant safety
factors into cost/benefit models and not rule out the implications surrounding extreme climate change scenarios. A
long-term, comprehensive (stakeholder orientated) and sustainable flood management strategy is crucial. It is far
better to be safe than sorry.
Mr. C. R. de Gouveia Souza [22] explaining a GIS based multi-criteria flood risk assessment and mapping approach
applied to coastal drainage basins where hydrological data are not available. It involves risk to different types of
possible processes like coastal inundation river, estuarine and flash flood, either at urban or natural areas and
fords. Based on the causes of these process, several environmental indicators were taken to build up the risk
assessment. Geo-indicators include geological-geomorphologic proprieties of quaternary sedimentary units, water
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table, drainage basin morphometry, coastal dynamics, beach morpho-dynamics and microclimatic characteristics.
Bio-indicators involve coastal plain and low slope native vegetation categories and two alteration states.
Anthropogenic indicators encompass land use categories properties such as: type, occupation density, urban
structure type and occupation consolidation degree. The selected indicators were stored within an expert Geo-
environmental information system developed for the state, which attributes were mathematically classified through
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deterministic approaches, in order to estimate natural susceptibilities, human induced susceptibilities, return period
of rain event, potential damages and risk classification.
[24]
According to Mr. O. GILARD & Mr. P. GIVONE Flood management is based on negotiation at a basin scale. All the
services, the decision makers, and representatives of the inhabitants, must work together in the development of the
basin and in the management of the land use. These groups have to discuss the vulnerability of this zone, and the
objective protection needs. This negotiation will be effective if a "quantitative risk unit" is laid on the table, making
possible exchanges between under- and over-protected zones (exchanges of vulnerability levels leading to future
land uses, not of lands themselves, of course). For effective use, they should develop hazard map as well as
vulnerability map. This way to design and to use a "risk market" at a basin scale is the best way to mobilize all the
diversity and potential of the landscape, to promote a better individual "cultural risk", and, finally, to avoid damage
in implementing a better land-use management policy.
The quantification of risks, future losses, and the costs and benefits of mitigation programs, though offering
valuable information, does not lead to any clear-cut guidance for the development planner on which is the optimum
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risk-reduction strategy to choose. The costs and the cost-effectiveness of alternative strategies are a necessary part
of the set of factors which need to be considered. But the intangibles, by their nature, cannot be quantified, yet they
must be given proper consideration. Further, the actual degree of risk and benefit must be judged against the
perceived risk, as indicated by the importance which the community attaches to any proposed expenditure on
mitigation. The distribution of costs and benefits among different sections of society has also to be taken into
account. Those who will pay and those who will benefit are not always the same people. Some people, such as land-
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owners or property owners may appear to lose more than they gain from mitigation strategies designed to protect
the lives and incomes of the poorest and most vulnerable. It is possible to modify cost-benefit analysis so as to
identify costs and benefits to different groups, but this exercise can lead to such a mass of data as to be
unintelligible. To adopt any strategy must be not only affordable, but also both publically acceptable and
institutionally manageable.
The aim of the Report[26] has been to map out the ways in which development can lead to disaster, just as disaster
can interrupt development. The DRI (Disaster Risk Index) work has shown that billions of people in over 100
countries are periodically exposed to at least one of the hazards studied, with an average of 67,000 deaths annually
(184 deaths each day). The high number of people exposed to natural hazard shows the scale of connection
between disasters and development. Recorded deaths provide a tip-of-the-iceberg measurement of the extent to
which past development decisions have prefigured risk. The Recommendations have highlighted a number of
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emerging agendas in disaster risk management that offer great potential for integrating disaster risk and
development planning. They also point at achievable policy and project actions that can be undertaken to reduce
risk in development.
Most fundamental is the role of governance at all scales from the local to the global. A balance between equity and
efficiency in the distribution of decision making power and in making decisions will need to be kept. A concern for
governance dovetails into more generic development planning policy. Like many of the proposals, the argument is
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for a change in emphasis and a broadening of development worldviews to take disaster risk seriously, rather than a
call for development planning perspectives to be rewritten.
Natural disaster risk reduction can provide a useful basis for adapting to climate change. Bringing the disaster and
climate change risk agendas and communities together should be a priority. The periodic nature of natural disaster
risk means it is often easily overlooked until it is too late and accumulated risk provokes disaster. Local risk
reduction will need to be sensitive to the multiple sources of competing risks people face. Governance regimes need
to work to reconcile the pressing need to respond to frequent and everyday risks, while avoiding the creeping
vulnerability that can lead to disaster risk. The work of linking disaster risk reduction to development planning,
offers great potential for advancing the cause of human development.
[20]
According to Mr. George P. C. Improper land use and development have significantly elevated the risks and
potential losses of human life and resources from future disasters. Although underutilized, controlled land use is an
indispensable tool for mitigating the adverse impact of disasters. Therefore, it is imperative that a disaster risk
assessment study includes or is followed up by a proper analysis of how the land should be utilized to mitigate
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disaster impact on a community. For the effective land use planning with respect to Disaster, one should consider
major aspects like Loss Estimation, Public Safety, Transportation Systems Construction or Modification, Sitting of
Infrastructure Facilities, Protective Defense Works etc.
Proper land use is probably the most effective method for mitigating the impact of future marine hazards, including
tsunamis. This tool is largely underutilized. Often, in allocating the use of land, the economic considerations are
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given higher priority rather than the overall safety of the community. Often, the use of coastal lands is permitted for
construction of critical facilities without proper or complete disaster risk analysis. To mitigate the impact of future
marine disasters along coastal regions that are potentially vulnerable to tsunami or storm surge inundation, local
governments should take steps to designate the danger zones that put parts of the population at risk by preventing
certain kinds of development. For example, critical infrastructure and industrial facilities should never be allowed to
be built in coastal areas likely to be flooded by tsunamis or typhoon surges, because that could compound the
effects of a disaster by the leakage or spilling of flammable or hazardous materials. Construction and development
should be prohibited in areas that put at risk the general population, but especially areas where the children, the
elderly, or the handicapped are concentrated. Critical facilities such as schools, and nursing homes should not be
built in coastal areas that are vulnerable. Similarly, police and fire departments and hospitals should be located in
risk areas. It is important that such facilities stay operational during the disaster and that they continue to function
effectively during the post disaster period.
Proper planning requires special information and evacuation procedures. For example, in coastal areas there should
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be posting of information and signs of evacuation procedures and routes to ensure the safety of the public. Early
warning systems and educational programs on disaster preparedness could help mitigate future losses. For
waterfront hotels in vulnerable areas, the staff of hotels should be familiar with procedures for evacuation and how
to pass this information quickly to guests. Such basic planning, preparedness and public education would have
saved many lives when the 2004 tsunami struck the waterfront resort areas in Thailand and elsewhere.
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Additionally, in constructing critical mega city infrastructure facilities in offshore and coastal areas that may be
vulnerable to disasters, engineering guidelines must be adopted that can assure safety and reliability and help
mitigate the impact of future events. Site selection for construction of important facilities requires careful disaster
risk assessments. First, all the environmental hazards that may be unique to a site must be examined. For example,
all available data must be collected on historical earthquakes, tsunamis, hurricanes, or surges. Then, each hazard
and its impact must be examined separately. Proper hazard risk analysis must differentiate between expected yearly
or seasonal occurrences and extreme events of longer cycles.
As a mitigate approach, the author[23] has suggested different alternatives like reduction in surface run off,
Transferring of flood water, Prevention of storm water contamination, Reducing riverine floods through infiltration
and evapotranspiration, Retaining/ transferring riverine floods, Delineation of risk zones, Definition of land-use for
different risk zones, Implementation of land-use regulations, Reducing physical vulnerability of people and
infrastructure, Reducing constitutional/economic vulnerability, Reducing informational/motivational vulnerability
etc.
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[25]
Prof. A. S. Arya and A. Agarwal had worked on “Multi-Hazard Resistant New Construction or Reconstruction of
BPL Houses in Flood Prone Alluvial Areas in India. They have explained the recommendations for renovating or
constructing new BPL houses. The major factor works for destructing shelter is soil erosion. Due to this, the bearing
capacity of the soil gets reduced and buildings of heavy materials may sink. The soil can be eroded under the action
of flowing water and scouring can take place around and under the foundations resulting in the uprooting of the
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lighter posts or sinking and tilting of the heavier foundations. Siltation can take place around the buildings when
the flood water recedes away from the site.
Based on the multi-hazard situation and prevailing alluvial soils with high water table conditions the following
criteria may be adopted for designing the houses:-
The foundations to be adopted should be resistant to erosion effect of flowing water, and also under the
liquefaction effects.
It will be appropriate to consider the plinth level of the house above the most common flood level in the area
and naturally above the drain level in the village.
The superstructure walls can be constructed using different materials like brick work, concrete block work,
stabilized compressed earth block work or lighter materials such as wattle and daub, bamboo matting
covered with mud plaster etc.. Also if the inundation level rises, the wall material should not become soft and
dissolve under water.
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As per the recommendations given by NDMA in the National Disaster Management Guidelines – Management of
Floods it is required that the houses in the flood prone areas should be made with flat horizontal roofs which could
be used as the shelter by the family.
In conclusion it should be emphasized that vulnerability and risk assessment can make two principal contributions
to the process of decision making in disaster mitigation:
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By considering risk as a framework for decision-making and quantifying costs and benefits, the decision-makers
(both development planners and political representatives) can obtain a clearer indication of the potential benefits of
alternative risk-reduction strategies, to complement other considerations in making a sound decision.
The same information can be used to increase the awareness of the general public, as an input to community
meetings, education or public awareness programs; and thus it can help lower the threshold of acceptable risk, and
make expenditure on risk reduction easier for decision-makers to justify.
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3.1 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
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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 defenses 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
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development planning according to the degree of risk faced and the risk a particular society is willing and able to
accept.
River basins are dynamic systems constituted by a complex arrangement of fluxes between the land and water
environment. There are essentially three interconnected fluxes, not only of water but also of sediments/nutrients
and pollutants. Surface runoff caries sediments, nutrients and pollutants from the land through the river system,
and as flooding occurs onto the floodplains as illustrated in Figure 1. It is important to note that those fluxes are
varying over time and space. Natural geomorphologic processes influence those fluxes to varying degrees. For
instance, natural phenomena such as land slides can have a significant influence on the sediment loads of adjacent
water courses. Those sediments are deposited in the drainage systems, reducing the conveyance capacity of the
channel and thus increasing the likelihood of flooding. Human alterations of the catchment area can significantly
contribute to changes to all those processes through large scale land use changes and land-use practices.
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An important process occurring during flooding is the extension of those fluxes into the floodplain, leading to the
deposition of sediments on the land. This has
Figure 3 Interaction between land and water environment
over the centuries created highly fertile alluvial
soils on the flood plains which on the one hand
can sustain high levels of biodiversity and on the
other hand have made those areas preferred
places of human settlement and agricultural
development. Depending on factors such as the
geomorphology and connectivity between the
river channel and the adjacent flood plain, other
beneficial effects may be observed e.g. that
fertilizers, salts and pollutants may be washed
out of the floodplain soil and groundwater
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increasingly difficult to establish with increasing spatial scale. For example the effects of certain land cover changes
on sediment load and peak flows can be established in smaller watersheds but on basin scales this is scientifically
not sufficiently explored territory. On that scales there are no simple cause and effect relationships but the system
that influences those parameters on larger scales becomes highly complex. Table illustrates these points by
providing an indication of observable impacts of land use on various parameters for different spatial scales.
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With increasing human alteration and development of the catchment area, the runoff generation process is changed,
especially through decreasing the infiltration capacity of the soil and the change of soil cover.1. This has lead to
concern over the role human alterations of the catchments play in increasing flood hazards. For example, a
commonly repeated element of media coverage and political initiatives on floods has been that the large-scale
deforestation leads to increased flood hazards. It needs, however, to be born in mind that while this may hold true
under certain circumstances, such as in small urbanized catchments, it does not imply that through employing a
conservation agenda for certain types of land uses, floods can be prevented, in particular on larger scales. The flood
formation process is influenced by various other factors for large scale floods especially the geomorphology of the
catchment area, and preceding rainfall conditions.
Hydrological responses to rainfall strongly depend on local characteristics of soil, such as water storage capacity
and infiltration rates. The type and density of vegetation cover and land-use characteristics are also important to
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understand hydrologic response to rainfall. Environmental degradation coupled with uncontrolled urban
development in high-risk zones, such as historical inundation plains and at the base of mountain ranges, leads to
an increased vulnerability of those communities on the floodplains to catastrophic events.
Saturated condition, or conditions quickly become saturated during the rainfall event, reduce infiltration of
rainwater. The consequences are most abrupt for hi-intensity rainfall over small, steep basins. The hydrology of
these catchments is determined by physical factors such as topography, geology, and vegetation cover.
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URBANIZATION
Urbanization disrupts natural 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.
AGRICULTURAL PRACTICE
Agricultural practices also have an influence on the runoff generation process. Various components of agricultural
practices can affect the runoff/infiltration process, including the following:
Soil drainage system: the availability and design of trenches, ditches or pipes in the soil which are utilized to
control the soil water content and groundwater levels on agricultural land,
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Soil tillage: especially the compaction of the topsoil and the orientation of the furrow,
Choice of crops planted and cropping patterns: each crop but also the amount of crop residues available on
the soil has on influence on the runoff and erosion process.
Slope of the field: terraced soils in steeply sloping areas can to a certain extent slow down runoff.
Apart of the general factors such as geology, topography, soil type and preceding rainfall conditions, runoff from
forested areas is also influence by the type of forest cover, especially the density of forest, the canopy and the soil
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cover. Significant changes to those parameters such as excessive logging, conversion of forested areas into other
land-use types, conversion of land through forest fires, have an impact on the runoff generation process and
erosion processes in particular on smaller spatial scales.
Next to land-use induced changes to the characteristics of the flood hazard, the way land resources are utilized has
a major influence on the creation of flood damage potential and the creation of vulnerabilities of local communities
to the flood hazard.
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. Depending on the availability of some level of flood defence, the overall
economic output from floodplain areas can be significantly higher than in other areas. This also is evident from the
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high population densities floodplains have attracted over time. With growing economies and the emergence of
wealthier societies, the damage potential from flooding is constantly rising. Flood damage potential can be defined
as the extent of possible damage in a given flood hazard area 3. This means that the benefits derived from the
floodplains are provided at a risk, i.e. the risk of having to bear flood damage. This flood damage can come in
various forms to buildings, goods, crops, infrastructure, or the environment. 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.
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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. However, in most cases the choice is implicit, e.g. by
deciding the location of a particular development, or by providing insurance cover to certain developments in flood-
prone areas. It is argued here that those implicit choices are too often taken without awareness of the prevailing
flood risks. This is the actual problem that has lead in case to unreasonable increases of damage potential,
especially where reasonable and less risk-prone alternatives may have existed. This trend can be observed in
various countries, not only confined to developing countries that may lack the means to undertake flood risk
assessments.
The overall flood management policy should therefore point in a direction where implicit and explicit choices are
possible under the awareness of prevailing flood risks and where those risks must be considered in the decision-
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making process.
A feature of popular debate about flood risk is the citation of total flood damage potential in river basins. 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
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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.
Apart from the damage potential the degree of vulnerability of various human activities to flooding plays a crucial
role in determining overall flood risk. Vulnerability can be defined as degree to which a socio-economic system is
susceptible or resilient to the impact of flood hazards. While this definition can also include flood damage,
resilience includes the aspect of how well the system is coping and is as such influenced by community’s
combination of prevailing social conditions and factors such as poverty and livelihoods6. For instance, if an
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emergency shelter or an essential access road is flooded, the structural damage may be negligible compared to the
problems this creates for the emergency response, in finding adequate alternatives and in consequence the safety
and well-being of the affected population and the speedy recovery process. Or in cases where means of local
income generation are disrupted or destroyed by flooding, such closure of as local factories, the recovery process
may be much more problematic, far beyond the direct damage to the facility. It is therefore essential to take count
of flood vulnerability as part of overall flood risk in land use-planning and regulation.
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One way of approaching this is through flood vulnerability classifications of different types of developments and
uses. Each class of developments can be regulated differently under the principle that the higher the vulnerability of
the development or use, and the consequential impact on socio-economic activities of the society, the lower should
be the flood hazard in the area where it is placed. If this is not possible, measures should be taken to reduce the
damage potential (through flood proofing or local flood defenses) or the vulnerability of the affected population.
The latter would for example relate to mandatory provision of evacuation plans or emergency response plans to
such developments. Some elements may be classified differently in different socio-economic conditions, for
example, in an area based on subsistence agriculture, where destroyed crops would present a major blow to food
security.
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4.1 OVERVIEW
The demand for flood risk assessment is derived from the type of the land use planning, distribution of population
density and the activities which runs the economy of the city. This chapter gives special attention to the aspects like
Regional linkages of the city, climatic condition, demographic trends, Economic activity and past flood experience of
the city.
4.1.1 BACKGROUND
Surat was famous for its food and now it is the “Silk City” of India. There are hundreds of Saree industries located in
the surrounding of the city. The city is one of the oldest historical trade centres of India. The historical development
of Surat dates back to 300 B.C. Surat was colonized by Brigus or the king from Sauvira on the bank of river Tapi.
Surat region during this period was known as “Lata”. In skanda-puran it is known as “Suryapur”, “Brahmpur”,
“Tapipur” etc. In the course of time significant Muslim domination changed its Hindu name “Suryapur” to “Suryt” and
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While there was a downslide in Surat’s economy since 1901, the foundations for the growth in the city w as laid in
the 60’s with the expansion of diamond trade, the gradual shift in the economic base into zari and textiles (power
looms), and the intensification of oil and gas exploration activities. Today, apart from the traditional industries of
textile manufacturing, trade, diamond cutting and polishing industries, intricate Zari works, the base has expanded
to gas based industries at Hazira.
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The events since the 60 are, seen in the city and the region, have resulted in a spurt in urban population in the city.
Surat continues to present a 6% plus annual population growth since 60’s, placing Surat 9th in terms of size
countrywide (2001). Parallel to the industrial expansion, Surat emerged as a major center for trade and commerce in
the region and a silent evolution has been that of the informal sector. While the city had a vibrant economy, the
focus was on growth with limited response to housing and services and the local administration did not translate
benefits of growth in terms of a financially robust local administration. The turnaround of the city of Surat
In the beginning, activities were concentrated with the inner wall, which had been constructed in the year 1664. An
area of the city at this time within this wall was 178 hectors. Access to the walled city area through 12 gates, viz. to
the north Variav gate, to the east Saiyadpura and Burahanpura gates, to the south Navsari and Majura gates and on
the west the Mecca and Badshahi gates and along the river front the Dacca owara, the Raja owara or the Custom
House water gates, Mirabehar and Lalgate. The outer wall was constricted in the year 1707, enclosing an area of
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736 hectors.
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In 16th century, Surat became a victim of various raids, the Portuguese raided Rander and Surat during 1513-1535.
On account of these raids emperor Akbar built the present fort of Surat during 1540-46. The port of Surat enjoyed
great prosperity from 16th to 18th century. However with the rise of Bombay port, Surat lost its port activities.
During the post independence period Surat experienced the growth in industrial activities along with residential
developments resulted into the expansion of city limits.
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Subsequent to the Plague of 1994, the city authorities undertook one of the most massive clean-up operations in
recent times and revamped the entire administration of the city. Within two years, Surat had been transformed from
the one of the filthiest cities to the second cleanest city in the country. A systematic process to upgrade
infrastructure, both quantitatively and qualitatively, has been made by the local government. The city governance
has come to be recognized as an example of a good governance system.
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In 1978 Surat Urban Development Authority was established including S.M.C. area cover in total area of 722.00 sq.
kms. Today Surat Municipal Corporation covers an area of 337 sq. kms. Until 1963 development was restricted in
only 8.18 sq. kms considered which was the walled city area. It was added to its in Municipal limit. After 4 years
northern area at Ved, Dabholi, Singapor, were included and again after 11 years period. Second expansion included
Nana Varachha, Karanj, Umarwada, Magob, Dumbahl, Adajan, Lymbayat, Dindoli, Bhedwad, Bhestan, Pandesara,
Udhana, Bamroli, Majura, Bhatar, Althan, Umra, Piplod, Jahangirabad and Jahangirpura, in year 1986.
The city of Surat is the commercial capital of the state and is of significant importance to the country. The Arabian
Sea is to its west at a distance of about 22 kilometres along the Tapi and about 16 kilometres by road. The city is a
pivotal centre on the Ahmedabad-Mumbai regional corridor as well as on the 225 km long industrial belt, having
direct linkages with the industrial urban centres of Vadodara, Ankleshwar and Vapi. National Highway 8 passes
within 16 km of the SMC boundary and is one of the busiest inter-state trunk routes in the country. Surat is located
midway on the 500 km long Ahmedabad-Mumbai western railway corridor and as many as forty pairs of express,
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mail and passenger trains pass through it. The city is well connected by road and rail with the major cities and
towns of the state as well as states of Maharashtra and Madhya Pradesh. The state government has also established
an airstrip to facilitate smaller aircraft landings and domestic air service has been started recently. Figure shows the
location of city in the Gujarat State.
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The city lies at a bend of the River Tapi, where its course swerves suddenly from the north-east to south-west. With
the walled city at its centre, the city forms an arc of a circle, the bends enclosed by its walls stretching for about a
mile and a quarter along the bank. From the right bank of the river, the ground rises slightly towards the north, but
the height above mean sea level is only 13 metres. The topography is controlled by the river and the general slope
is from north-east to south-west. The summers are quite hot with temperatures ranging from 37˙ C to 44˙ C. The
climate is pleasant during the monsoon while autumn is temperate. The average annual rainfall of the city is 1143
mm.
Due to rapid industrialization, with the large establishments of KRIBHCO, L & T, ESSAR, NTPC, Reliance industries
etc. and in addition to the normal development of the traditional textile industries, diamond industries and
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construction activities, Surat has become an important growth magnet for the migrants. Also relatively peaceful and
harmonious social environment and moderate climate has converted the migrants into permanent settlers in the
city. This resulted in higher decadal growth compared to any city in the state in last two decades. This statistics of
the population of the Surat city from census year 1901 to 2001 is contained in Table 4.1 highlighting centurial
increase in city area by about 14 times coupled with about 20 times increase in the population. Graph 4.1 depicts
the decadal population figures showing abrupt raise in population after 1981 highlighting effect of in-migration.
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Surat city has seen an exceptional growth in last four decades recording one of the highest growth rates in the
country and a 10-fold population rise. The City now ranks the 9th largest city in the country. Coupled with this the
spill over of population into periphery has also been observed. From time to time jurisdictional limits of SMC have
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also been extended to include the outgrowth. At present SMC area is about 334 Sq. Kms. which was 112 Sq Km
before the recent city limit extension in July 2006. There are about 6.50 Lac people (2001) reside in the immediate
periphery of the city. Yet, with the growth in population sex-ratio figures are continuously falling which is not a
sign of healthy progress.
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Table 3 Population and Sex Ratios: in comparison with other urban agglomerations in the State
During 1991-01, the city experienced an exceptionally high decadal population growth rate of 85.09 percent. Rapid
inflow of population is continuing. The sex ratio has dropped down to 774 in 2001 from 839 in 1991. A positive
feature is that the literacy rate has gone up from 63 percent in 1991 to 83 percent in 2001 and the figures are well
above that of the state. This may also mean that the city received more literate and hence better quality human
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Surat is know n for its textile manufacturing, trade, diamond cutting and polishing industries, intricate zari works,
chemical industries and the gas based industries at Hazira established by leading industry houses such as ONGC,
Reliance, ESSAR, and Shell. The city economy is characterized by large number of small and medium size
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unorganized industries. The industrial base is labour intensive. Of the total 2,78,656 small scale units registered
(2003) in the state, Ahmedabad and Surat districts leads the list with high number of small scale industrial units at
61,185 and 41,509 units respectively constituting 21.96% and 14.9% of total SSI units in the State. The share of
Surat has increased from 12.6% in 1980 to 15.1% in 2005.
In terms of factory sector also the share of Surat is significant. In Gujarat, there w ere 3911 registered factories in
1960 employing 3.46 lakh workers which increased to 27,089 registered working factories employing 7.78 lakh
workers (2001). In 2001, Surat district accounted for 1900 units employing about a lakh and thirty five thousand
workers.
Much of the industrial development is located within the limits of Surat city. In fact Surat is truly an industrial city
with over 50% of workforce engaged in manufacturing activity. While the problem of unemployment is almost non-
existent, the wages are also lower and the workers are generally deprived of social and other benefits. The detailed
account of sub-sectors of the economy is presented below :
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Surat is a dominant player in the textile sector. The traditional handloom weaving industry has given w ay to power-
looms, printing, and dyeing textiles. Surat is one of the largest centres in the world for production of synthetic
fabrics, mainly nylon and polyester. The Indian Government’s policy since 1956 of providing incentives and
protection to small-scale industries boosted the power-loom industry in the city. Weavers took advantage of the
incentives and converted their handlooms into power-looms. At present, there are about 0.6 million power-looms
(about 60,000 units) in the city region and the sector provides for over 1.2 million jobs in Surat. The total
production value of “Gray Fabrics” in Surat is about Rs. 20,000 Crore. The textile processing units are the major
backbone of the Surat city’s economy. How ever, they depend mainly on ground water for its processing and
withdraw about 700 to 1000 cubic meter of water every day.
There are about 60 thousand shops and establishments engaged in trading activity in general with textiles as a
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predominant sector.
Surat is the home of zari industry in India which dates back to 16th Century. Imitation and real zari threads, zari
embroidery materials, zari laces and borders are manufactured in Surat. Over the years the industry has faced
numerous problems. The strong w ill of the craftsperson and the enterprising spirit of some of the people have kept
the industry alive even in the face of many onslaughts. Today there are above 6750 zari units that employ
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approximately 47500 workers. An apparel park has also been planned in the city for production and export facilities
to be under one roof and to give a face-lift to the textile industry.
Gujarat accounts for almost 80 % of the diamonds processed in India. Of this, 90 % are processed by the units
located in and around Surat alone. The emergence of the industry in the region which did not have raw material,
markets or worker base is a significant feat. Even majority of the entrepreneurs are from outside. Initially the
industry began largely as an initiative of few individuals belonging to a particular community which has now
expanded to large section of the society. Under the Import Replenishment Scheme introduced by the Government of
India in 1958, diamond traders were allowed to import rough diamonds from Diamond Trading Corporation,
London and other sources abroad and export cut and polished diamonds. Added support came from the
encouragement offered to small-scale industries during this time. By the late 1950s, about 100 diamond cutting
and polishing units had been set up. With the setting up of the Gems and Jewellery Export Promotion Council in
1966, diamond exports received a further impetus and consequently, the number of cutting and polishing units
also increased. Coupled with ease of establishing small-scale industries, various governmental policies aimed at
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increasing the export of polished diamonds aided the growth of such units in the city.
Hazira area spread over 167 sq. kms is a major industrial area located in contiguity with SUDA limits. Magdalla
lightrage port which also includes captive jetties of M/S ESSAR, RIL, L&T, GACL, and KRIBHCO provides sea
connectivity to the region. Hazira Port Pvt. Ltd is being set up by Shell International. Given the nearness to Surat city
and the port connectivity, Hazira region accommodates 20 large and medium sized industries. They are producing
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polymer, heavy engineering products, gas, LPG bottling, steel foils, ammonia etc., The total investment in the Hazira
belt exceeds Rs 20,000 crore.
Surat has been a flood prone area since centuries. The city has witnessed major floods in varying intensity in 1883,
1933, 1942, 1944, 1945, 1949, 1959, 1968, 1998, and 2006.
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The above data on floods indicate a broad pattern of regularity in their occurrence across time. Since 1869 upto
1884, on an average the city was flooded every two and a half years. This was followed by a flood every three and a
half years during 1914 to 1949. During 1949 to 1979, the corresponding average of flood occurrence came to once
every four years followed by their occurrence nearly every six years between 1979 and 2006 with the Ukai dam
having already come up by 1970. Such regularity indicates at a natural tendency for Tapi to flood especially its
downstream settlements including the city of Surat.
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The trend shows that the flood prone areas are increasing since 1994. The total area affected by 1998 flood was
23.5 Sq. Km whereas in 2006 flood it is 128 Sq. Km.
Table 5 Yearwise Max. reservoir’s Water Levels and Annual Max. Release from Spillways
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The floods in Surat have been often due to heavy rains in the upstream regions, they have also been compounded
by the unpredictable storms in the Tapi basin. Together these add to an uncertainty in the pattern of recurrence of
floods in the city as a flood having an intensity of 23 lakh cusecs may actually occur within a few years or a flood of
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a much lesser intensity of even less than 5 lakh cusecs may not occur even within the next ten years. This is
because of the change in climatic conditions.
There are various reasons for flood in Tapi river. These are both natural as well as human induced. The natural
reasons are:
Heavy precipitation in the catchment area: Even with a differential precipitation rate in the larger catchment but a
higher rainfall within the catchment of a smaller tributary may lead to heavy flooding.
Cyclonic Storms: The storms caused by the depressions in the bay of Bengal and moving in the west and north west
directions and passing over the Narmada and Tapi basins and coming in contact with the south-west monsoon
winds causes heavy storms and downpour. These cause floods in the river. Such depressions are unpredictable and
uncertain and thus the floods in the river is also becoming uncertain with time.
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Effects of Tides and Siltation: The tides further raise the water level aggravating the floods in a highly silted river
bed.
Effect of railway embankments: The railway embankments at the higher elevations for Surat-Ahmedabad, Kim-
KRIBHCO and Reliance have restrained flood spread, increased the flood depth and generated a parallel flow to the
river in areas that were never subjected to flood before.
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Effects of the city growth: Since the mid seventies, Surat has been witnessing a rapid growth in terms of commerce
and industrial development. In course of attaining the development, even the areas which have been the natural
flood routes have been rapidly consumed for development. There are various ongoing and proposed projects in
these areas.
In 1968, most parts of Surat city were flooded. in 1998, 30 percent had gone under water and in August 2006 more
than 95 percent of the city was under Tapti waters. The 2006 Surat floods created an intensely high devastation to
the entire city. There was Heavy precipitation and continuous downpour in Tapi basin which resulted in in an
unexpected outflow from Ukai in an excess of 9 lakh cusecs for almost 24 hours.
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Various reasons have been given for the August 2006 floods in Surat. There has been a relationship between the
floods and the Ukai dam on Tapti river. According to many people the dam have caused and enhanced the flood
situation.
Ukai Dam
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Ukai dam is the largest multipurpose project which is undertaken by the State. This project was accepted by the
Planning Commission in 1961 and the work actually began from 1966 onwards. The main aims of ukai dam were to:
Providing irrigation primarily to regions under the Kakrapar command area and other areas as well through
canals taking off directly from its reservoir.
To generate an average energy of 1060 million units (MU) every year
To provide effective flood protection to areas lower down including Surat city.
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Ukai Dam
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Figure 8 Ukai Dam SnapShots
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On receipt of the warning about the incoming floods from the upper reaches, the storage in the reservoir has been
planned to be depleted in advance by suitably regulating the outflow and thereby creating a space in the reservoir
for detention of the incoming flood. The dam has spilled during 14 of the 27 years. Recent capacity survey
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conducted by the Gujarat Engineering Research Institute (GERI) , The original gross capacity of Ukai reservoir was
8511.01 Mm3 and the revised capacity as per 2003 survey is 7414.29 Mm3. The total loss in gross storage capacity
is 1096.72 Mm3. Moreover the silt rate as per the design is 1.49 ham/100km2/year whereas the silt rate as per the
2003 survey is 5.686/100 km2/year.
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Due to heavy rainfall in Maharashtra in the catchment area of Ukai Dam, inflow into Ukai Dam started increasing in
the first week of August. The State Irrigation Department monitored the inflow, outflow and maintained water levels
in the dam based on these and on the forecasts of the Central Water Commission (CWC). The excessive outflow into
the Ukai Dam downstream has affected a large number of villages along with Tapi water course as well as city of
Surat and the industrial hub of Hazira. With the entry of flood water into villages, urban market and residential
areas, and industrial units, the active pace of life in Surat district has been disrupted. The nature of the flood water
and the rise in the levels within the city has caused people to shift to higher levels and many have lost their means
of livelihood and household goods. Industrial units have ceased production temporarily. As a precaution, power
supply in many areas has had to be switched off to prevent the people from being electrocuted. The water supply
system in the city has been contaminated with mud water and was not operational. The roads and pathways have
become inundated with water. There has been a complete breakdown of social and economic life.
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Irrigation (Panchayat) 30 30
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The floods in Surat city and nearby areas caused widespread damage in all the industrial sectors (Large and Medium
industries, Industrial estates and Cottage industries). Large scale loss and damage was suffered by commercial,
trading and service establishments, which were mainly in the basement, ground and first floors in all the parts of
the city that was flooded. The damage to these sectors is in buildings, finished stock, furniture and fixtures.
The floods in Surat city and nearby areas caused widespread damage to a large number of industrial units. The
areas and industrial sectors affected are as under.
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Of the different industrial sectors, the power loom textile industry has suffered severe damage to buildings,
equipments and inventory.
Power looms: About 1,15,000 power looms, mainly amongst 18,000 micro and small units located in Katargram,
Ved Road, Limbayat and Varachha Ajan have suffered damage.
Jari Industrial Units: Jari industrial units are of cottage and micro nature located in the city. It is estimated that most
of the 700 units have suffered damage towards buildings, equipments and inventory.
Textile Industry : Severe damage has also been faced by the textile market located on Ring Road in Surat. Of the
140 large textile markets, 40 markets have suffered damage because of flood. The units in basement of these
markets have suffered total loss of inventory/stock.
Processors 25
Embroidery 50
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Jari 50
Total 585
Source: GSDMA Flood Memorandum
9%
9%
4%
2% Power looms
Shuttle less looms
Processors
Embroidery
Jari
77%
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Diamond Processing Units: There are over 8,000 micro and small units, of which 3000 units have suffered damage
towards buildings, machinery and office furniture etc. In addition, 3000 of the 5000 jewellery units, which are in the
nature of ‘home industry’, have suffered damage to machinery and tools.The units in Hazira area, mainly ONGC,
GAIL, IOC, NTPC, KRIBHCO and L&T have suffered severe damage and losses of equipments, installations and
inventory.
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Diamond Units(machinery loss, laser machines, auto cutters) (No.of units = 400
800)
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15
400
GIDC has one industrial estate in Surat, which is in the immediate vicinity of Tapi river, namely Katargam Industrial
Estate. Katargam industrial estate which is in Surat Municipal Corporation’s area wherein 38.00 hectares of area
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with physical infrastructure of road and water supply distribution network of 7.00 kms comprise of 800 units was
badly damaged. It was observed that during recent flood, both these industrial estates were heavily flooded and as a
result, huge amount of mud along with debris were stuck up on the roadside and within the sheds. Also it caters to
the the needs of Big industries like ESSAR, L&T, Reliance, Shell, I.O.C etc. was heavily impacted During present
monsoon, roads off-taking from N.H. 6 in this area were badly damaged.
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The Surat city was impacted the most in terms of damaged to roads, water supply and sewerage network, clogging
of drains, damage to river banks, electrical installations and networks etc. suffered extensive damages to Urban
infrastructure, Power and Irrigation sectors.
The Surat city was impacted the most in terms of damaged to roads, water supply and sewerage network, clogging
of drains, damage to river banks, electrical installations and networks etc. The Urban Development Department
suffered an estimated loss of Rs 148.07 crore towards damage to its infrastracture in the Surat district.
The Irrigation sector with its water resource department suffered the maximum impact with widespread damage to
the river embankments and canal systems
Housing 198.00
Finance 518.16
Irrigation 399.63
Power 325.63
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Agriculture 5.68
Health 9.36
Home 10.00
Education 24.49
TOTAL 17985.94
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It can be inferred from the above table that the highest loss is incurred by the Industries and Mines sector which is
to the tune of 16236.69
Engineering Goods 45
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Efforts were made by the government to provide relief to the affected people. However the non availability of a
defined relief centre frequently created confusion as to where the relief material should reach first for their
distribution. The CSS-VNSGU survey revealed that much of the relief came from neighbours while the administration
and the NGOs had a restricted outreach. The modalities of coordinating the NGOs efforts as per the prescribed
manner and norms in the disaster manual did not succeed. Hence much of the efforts and relief efforts and relief
operations conducted by NGO’s, individuals as well as villagers residing at locations surrounding the city were
characterized by their own perceptions and understanding of the situation.
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b) Others 80
Relief Centres 52
Over 4,23,000 persons from the severely affected Surat City were evacuated by administrative efforts and
were shifted to safer locations. About 1,907 relief camps were opened providing relief to the evacuates and were
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provided with household kits. Massive cleanup operations were launched post floods in the Surat city. 172 JCB’s,
331 tractors, 452 trucks, 409 dumpers and 14 water tankers were put into service. About 150 dewatering pumps
were used to remove water from the low lying areas and basements of buildings. In addition, 439 dumpers were
also sent from Saurashtra to Surat. Over 6.3 tonnes of waste/silt was removed from the city.
Around 64 water tankers were deployed by the water supply board to provide drinking water in the Surat city. 171
lac food packets including 138 lac food packets for Surat city have been distributed so far all over the affected areas
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and 138 lac drinking water bottles and pouches have also been distributed in the Surat city itself. 1,50,000 family
kits were also prepared for affected persons in the Surat city.
800 ration shops, whose stocks were destroyed in the rains/floods are being re-stocked and 11 mobile vans are in
operation. 20 trucks of petroleum products have reached Surat and daily supply of 44 KL is planned.
To meet with the demanding situation and to support the city administration in rescue and relief, helicopters of the
Air force were deployed into service. Rescue operations were conducted with the help of Armed Forces and Fire
Services from the Municipal Corporation of Surat.
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Insecticides sprayed :-
A) Powder 3202 MT
B) Liquid 80 KL
The above table shows the support provided to the people in terms of health. Entire city was disinfected.
Table 15 Relief
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The above table shows the relief provided by the government to the people after the flood. However the general
perception is that the relief was not satisfactory.
Table 16 Engineering
More than 25, 000 tonne disposed daily against average daily disposal of 1000 tone. There was large scale silt
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deposition in the entire city. Entire silt was taken and dumped outside the city. Moreover a commendable job was
done on the part of the government in restoring the basic facilities of water supply, drainage and electricity.
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Electricity
The above table shows the percentage restoration of the services such as water supply, drainage, electricity, street
light, domestic and industrial water supply immediately after the floods.
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5.1 GENERAL
Surat Urban Development Authority (SUDA) has prepared development plan for Surat Urban Development
Authority limits including corporation limit which has been sanctioned by Government Notification No. GH/V/46 of
1986/DVP/1481-364 (86)/L dated 31/3/86. SUDA has prepared the revised Development Plan in 1996 and
submitted to Government in 1997 for sanction. Surat Urban Development Authority has also prepared Town
Planning Scheme No. 1 {Udhna – Majura) and Town Planning Scheme No.2 (Udhna). These preliminary schemes have
come into effect from March 89 and January 88 prepared twelve Town Planning Schemes which have been
sanctioned and implemented. Draft Town Planning Scheme prepared by Surat Urban Development limit area being
followed up at different levels for final sanction. These are namely Town Planning Scheme No.3 (Kamrej), Town
Planning Scheme No. 4 (Umra-South) Town Planning Scheme No. 5 (Umrea North), Town Planning Scheme No. 6
(Piplod) Surat Municipal Corporation has also taken Town Planning Scheme No. 13, 14, 17, 18 for Adajan, Rander,
Fulpada & Katargam area which are at different stages of finalization. Still majority of the Surat Municipal
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Corporation area remains unplanned. In order to plan new areas which are fast developing, scheme for Rander is
taken next.
The scheme under reference known as Town planning scheme no. 23 (Rander), forms along the western side
abjuring Tapti. The development of T.P. Schemes No. 11, 12 and 14 have left a small segment along the river
approximating 72 hectares as unplanned which is being taken up in the present Scheme. Moreover SUDA in its
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revised development plan has earmarked a large chunk of land approximating 33 hectares in the Scheme area as
Reservation under Recreation by leaving approximately 40 hectares land for other development in the Scheme.
The Scheme under reference is known as Town Planning Scheme Surat No. 23 (Rander). The Boundaries of the
Scheme area are shown in plan No. 1 of the Document. The area of this Town Planning Scheme is about around 79
hectors. The physical Boundaries of the Town Planning Scheme are as under.
The Northern side is the boundary Town Planning Scheme Surat No. 14 (Rander – Adajan). The Southern side
is bounded by Town Planning Scheme Surat No. 11 (Adajan). The Eastern side is bounded by River Tapi. y. The
Western side is bounded by Town Planning Scheme Surat No. 14 (Rander – Adajan).
a. The Scheme area includes R.S. No. 290 to 356 & 372 of village Rander.
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b. The eastern part of the Scheme area along the river is part of embankment required for protection, while the
western part of the Scheme area is situated in residential zone. The Southernmost part of the Scheme area
adjoining the Scheme is having Residential development in Town Planning Scheme Surat No. 11 (Adajan).
c. The Scheme area is planned for approximately 3800 persons uniformly Spreaded over 79 hectors of the T.P.
Scheme. In light of this and considering the trend of development, the entire area is planned for, Residential
use with basic asininities, like school, garden, play–ground, shopping, district center. In addition to this there
are provisions for other public purposes such as Commercial, public services and public utility center. Also
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reservation for recreation for the entire city is planned to be accommodated as part of revised development
plan proposals Also the reservation for housing for socially and economically backward class of people as
provided in the act.
d. The entire area is provided with network of roads of varying width ranging from 9m to 30m. The individual
original plot areas are uniformly reduced to create additional land for roads and amenities. Effect has been
made to allot final plots from respective original plots as possible. The percentage deduction of plot area
varies from 20% to 30% on an average in draft scheme, uniformly distributed in the entire scheme area where
the plots are open and undeveloped.
e. A 24.38 Mt. Wide road is proposed parallel to the river Tapti which links major roads of T.P. Schemes 11 and
14. Major Roads of 18 Mt. Forms the main arteries of scheme. Various other Roads of 12.oo Mt. wide, 9.00
Mt. wide and 7.5 Mt. wide are provided to link these main roads for the safe and speedy traffic movement
within the scheme area. Each and every final plots are made accessible from T.P. road.
f. Keeping in view the above aspects the town planning scheme has been prepared which will provide a planned
and controlled residential and recreational redevelopment for this part of the city in terms of roads, open
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spaces, public amenities and utilities and at the same time it will also provide well developed plots to the
owners of the land. Care has been taken to provide infrastructure like street lights, water supply, Roads,
Drainage and Storm water drains alongwith open spaces and public reservations.
Before making town planning scheme, the chief town planner Town Planning and valuation department,
Gujarat state has been consulate by the appropriate authority (Surat Municipal Corporation) and requisite consent
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has been given by the chief town planner vide letter dated 23/04/92 as required under section 41(1) of the Gujarat
town planning and urban development Act, 1976.
Town Planning Committee of Surat Municipal Corporation under the resolution No. 28 dated 28/8/92 declared it’s
inaction of prepare the above draft Town Planning Scheme No. 11 as section 41(1) of the Town Planning and Urban
Development Act 1976. The declaration of intention to prepare the Scheme was published in Extra Ordinary
Government Gazette dated 12/9/92. The said declaration of intention was also published in the newspapers namely
‘New Gujarat Times’ and “Gujarat Mitra” on 15/9/92.
Owner’s meeting was held at 10.30 A.M. on 29/4/93 in the Gandhi Hall at S.M.C. explain the tentative
proposals of the draft Town Planning Scheme No. 23 (Rander) Surat to invite suggestions /objections from the
interested persons. Individual notices were served and a owners whose addresses were available from the records
and a public notice was published in local daily news paper ‘New Gujarat Times’ on 21/4/93 inviting participation
from interested persons. The above Notification was also published in the official Gazette for inviting suggestions
and objections as per section 42 & 47 of the Act.
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Thereafter the Draft Town Planning Scheme Surat No. 23 (Rander) was prepared and published in the official
Gazette on 26/8/93 in Central Section Part II Extra Ordinary on page No. 18-19. The Notification was also published
in the local newspapers ‘Gujarat Samachar’ and ‘Gujarat Mitra’ on 26/8/93 inviting objections / suggestions as per
resolution No. 29 Dt. 12/8/93 of Town Planning Committee of Surat Municipal Corporation.
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The administrator of Surat Municipal Corporation has resolved under resolution 47 in the meeting dated
17/2/93 to submit the draft Scheme to State Government for sanction as provided under section 48 of the Gujarat
Town Planning and Urban Development Act, 1976.
The Government of Gujarat, after examining the Draft Scheme proposals had sanctioned the Draft Town
Planning Scheme Surat No. 23 (Rander) under section 48 (2) of the Gujarat Town Planning and Urban Development
Act, 1976 vide Urban Development and Urban Housing Development Notification No. GH/V/ 404 of 1994
/TPS/1493/3954/L dated 19/9/94 subject to the modifications. (Schedule of Draft Town Planning Scheme point No.
1 to 8) The said notification was published in Gujarat Government Gazette.
The State government under section 50(1) of the Gujarat Town Planning and Urban Development Act, 1976
appointed town planning officer, Fulpada-Kapodra as a Town Planning officer to finalize the said Draft Scheme, vide
Urban Development and urban Housing Department Notification No. GHV/1994 of 572/TPV/1094/2246-V
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Dt:28/11/94 which was published in Government gazette part IV – B page 233. Shri A.K. Desai who was holding the
charge of town planning officer at that time has entered upon his duties on 19/04/95 and published notices
inviting claims for injurious affection from the owners of any right which injuriously affected by making of draft
Town Planning Scheme under section 82 of Gujarat town Planning and urban Development Act 1976 as well as
inviting objections on the Draft scheme proposals from the persons interested in the plots and affected by the
scheme proposals in prescribed period under the provisions of the rules 26(1) of the Gujarat Town Planning and
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urban Development Rules 1979 which was published in Gujarat Government Gazette part – II Dt; 4/5/95 page no.
192.
The government of Gujarat under its resolution of urban development and urban housing department
Dt:10/10*95 has P.V.P.C.Prasad as Town planning officer, Fulpada – Kapodra.
As a town planning officer have conducted the further proceedings under the town planning act and have
done all that is required to be one under the provisions of the Gujarat town planning and urban develo9pment act
1976 and the rules made there under time to time so as to finalize the draft scheme and to draw up this preliminary
scheme.
The general proposals and provisions made in the draft town planning scheme Surat no. 23 (Rander) are
mentioned in brief as under
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1. Roads
A. Proposals have been made for widening and improvement of existing roads and laying of new roads for
giving approach road to each final plot in the scheme area. Providing basic services such as water supply,
drainage line, Storm water line, and street light in the Scheme area, making each plot regular in a size,
allotment of final plot to the owners in view of original plots.
B. Eastern side of the T.P. Scheme is bounded by river Tapi. The road is proposed in parallel as 24.38 Mts..
wide linking the T.P. Scheme of 11 and 14. Bridge is also Planned to connect other side of the River Tapi.
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C. A roads of 18.28 Mts.. wide connecting the Roads of T.P. Schemes 11 and 14 and passing through western
side of the Scheme area is proposed through survey nos. of 337, 294, 295, 296, 306 and 307 forming the
main arteries of Scheme area. Three roads of 18.29 Mts. are proposed to link the western and Eastern
Roads.
D. A 12.19 Mts. roads are proposed on the existing Nal Roads and part of them carved earlier in T.P. Scheme
14.
E. Two roads of 9.00 Mts. width are proposes in the Scheme area. One connecting survey No. 306, another
road is proposed in the Scheme connecting R.S. Nos. 310 to 312.
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Keeping in view of the requirement planned and control industrial development the following Reservations are
proposed in Draft Town Planning Scheme.
(Sq.Mt.)
R2 GARDEN 969
R3 GARDEN 2136
R4 PARKING 305
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(Sq.mt.)
Residential 302719.13 38 %
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E W S Housing 11026.32 1%
Commercial 10769.16 1%
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20%
4%
38%
Residential
Road Network
1% E W S Housing
2% Public Buildings
Commercial
1% Recreational Purpose
Land for Pala Yojana
33%
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The Ukai Dam is constructed in 1972 with consideration as partial flood control scheme with moderate flood
of 8.40 lacs cusecs. The industrial city of Surat which is heavily populated and the flat fertile land in this area are
severely affected several times by floods in the river.
The state Government decided to protect Surat city and its adjoining area from flood of river Tapi and
approved the Tapi Flood embankment scheme amounting to Rs. 5.83 crores.
After construction of Ukai Dam in the year 1972, there was no heavy flood in the river Tapi up to 1994.
During 1994 and 1998 flood, there were flood to the tune of 5.25 lacs cusecs and 7.00 lacs cusecs respectively.
Due to heavy flood of magnitude of 7.00 lac cusecs in the year 1998, the flood water entered in the Surat City and
the surrounding area through remaining flood embankment. Immediate restoration works were completed.
Due to construction of Singanpore weir in the year 1995, the C.W.P.R. S., Pune has suggested to raise the
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embankment by 1.90 mt. in 22 Km length in the U/s. of Singanpore weir up to Kathor. During 1998 flood, the flood
protective measure on river Tapi in Surat City and surrounding areas proved to be insufficient on account of (1)
afflux caused due to Singanpore Weir (2) Heavy silting in the river channel (3) Construction in flood plain area. As
regards the afflux caused due to Singanpore Weir, it is to emphasis that during 1998 flood, afflux actually observed
was about 2.30 mt. at 7.00 lacs cusecs discharge.
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The TP scheme 23 is located on the bank of river TAPI. So whenever there was heavy flood in the city, the area
under TP scheme no 23 had suffered with great susceptibility. The scheme is also includes the part of flood
embankments which had an approximate length of 2336.00 Mts. with one flood gate but the height of the
embankment is not sufficient to divert the flood water from this particular area. Some of the basic detail of the
embankment is showing below.
Length in mt. Probable final Expenditure Qty. to be executed Qty. Executed Physical progress (%)
expenditure (Rs. incurred up to
Earth work in Gabion in Earth work in Gabion in Earth work gabion
In lacs) 6/2009 Rs. In
Cum. No. Cum. No.
Lacs
Present safe carrying capacity of Tapi River at Rander in downstream of Nehru Bridge near Surat city limit is
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approximately up to 3.50 lacs cusecs. Safe carrying capacity of Tapi River in Amroli, Chhaprabhatha, Variav,
Jahangirpura, Katargam, Ved, Dabholi, Singanpore, Tunki, Fulpada and Kapodra will be about 9.00 lacs cusecs after
strengthening of existing banks without freeboard.
The river basin is also loosing its water carrying capacity due to sedimentation. From the study of contour
map, we can conclude that the average rise of the area is about 8.0 Mts. to 8.5 Mts. from the mean sea lvl. If we
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consider the average flood levels at Nehru bridge during past floods, we can conclude that the height of the water
column was above 8 Mts. Please check the below table.
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14 1954 09.98
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25 2002 08.20
So from the above table it shall be clear that the area is under frequent flooding. It can be say that whenever the city
is under the influence of flood the study area is at high risk of flood. So it means rather to protect the area from the
flood water, it’s better to apply mitigative approach like living with flood. For that travelling time of water from Ukai
dam to our study area must be known.
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Below chart shows the travelling time of water from Ukai dam to singanpore weir which is nearer to Town planning
scheme no. 23.it is shown that the water released from the Ukai dam takes 7 hours and 45 minutes to reach in to
the study area. If proper and timely information is provided than people can survive from the flood hazard and also
saves their property from the damage.
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The contour of TP 23 area (as shown in Map 4) is somewhat like mild slop. The height of the ground elevation
is maximum 9.5 Mts. and Minimum 7.0 Mts. The average rise of the ground is about 8.0 Mts. The attached map
shows the detail of contour map. From the contour map we can indentify the criticality of particular area with
respect to flood water coverage. We can also build the water flow diagram and from that flood response map.
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As Per the above talk, if the situation of 2006 flood is again occur than the situation will become something
like this. In this situation water can easily entered in our study area which will lead to heavy flood. It can also breach
the embankment. If water in the river increase above 8 Mts., it means our all drainage system in particular TP 23
area is going to be fail. They all could be the entry gate for the flood.
In next chapter, we will discuss about the flood mapping and its impact on the people living in TP 23 area.
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6.1 INTRODUCTION
This chapter focuses and attempts to identify properties and land resources at risk in other words, the vulnerability
analysis of the properties or spatial risk identification due to floods in River Tapi in the delineated area of T.P.
Scheme 23 of Surat. To begin with the risk analysis, it is essential to derive the actual status of built properties in
the identified area. Based on this, a Building typological survey is performed to derive the actual spatial extent of
development with identification of building type and classified major uses. Notably, there are 33% of raw houses
and 24% of bungalows which indicates that the residents in this area belong to MIG- HMIG class. Further, it was
reported that out of total built properties, 16% belong to slums that further increases the level of risk to human
lives during an adverse situation. However, with regulated vertical development the low rises share 11% and high
rise building share 10% of total built up properties.
With availability of information and data regarding the existing ground levels, an attempt is also made to work out
the pattern of the surface flow occurrence in case of flooding water. Within the project area it is analyzed with
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increase in water level, how much of land area is vulnerable to flooding. With a maximum difference of 2 Mt of
water column depth, the inundation maps are prepared showing the location of the roads as well as various plots.
Further the ground level of the surrounding area is also studied and variations in the natural ground slopes have
been obtained. This shows formation of islands in the entire area wherein important buildings can be constructed
with low risk so as to utilize the same as place of rehabilitation purpose at hours of emergency. The remaining area
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was demarked on maps showing the probable level of inundation as part of risk analysis. The study is not the based
on the flood 2006 data, as this type of flood is occurs once in long history.
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There is always probability to found difference between the maps in the office and existing condition in field. For
carrying out liable flood risk assessment, It is necessary to carried out actual field survey for awareness of building
typology of the area. Typological data plays very important role for identifying the properties at risk of probable
flood. It plays very important role for making flood response map also. It is necessary to differentiate the area from
macro to micro zone. Classification of the developed area with respect to Infrastructure and Habitant’s facilities
shall be carrying out. Below map no. 5 shows the Existing condition of the Town planning scheme no 23 of surat
city.
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27%
35%
4% 33%
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Map 6 T.P. Scheme no. 23( Showing Reservation)
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The above map 5 shows the existing land use condition of the TP 23. Here it is clearly seen that the white area
which is running parallel to the main road is Embankment constructed for diverting river water at the time of flood.
The final plot allotted on river side of the flood embankment can only used for the recreational purpose or for
farming as the area belongs to coastal regulatory zone. From the table, it is clearly seen that the TP 23 is not that
much develop with respect to habitant. The vacant land for development is more than the develop area. People’s
mentality is to divert their residential location choice far away from the bank of river as they aware of frequency of
flood in the city. The Surat Municipal Corporation had also put the reservation for the socially and economically
backward class people house, for garden, for commercial activities and for public buildings. The Road network in
the TP scheme is well defined and approaches most of the plots directly (Refer Map 6).
The building forms are further classified in different categories like Row Houses, Bungalows, Low Rise (G+5), High
Rise (G+6 and above), Commercial, Commercial cum Residential, Educational, Religious Place, and Encroachment in
the vicinity. The scenario of the TP area can be projected from the above data. It will be helpful for projecting living
condition for different categories of the people like HIG, HMIG, LMIG, LIG and EWS. Below table shows the Area and
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From the table, It is seen that the most of the people living in the Town Planning Scheme No. 23 of Surat city are
belongs to the Higher middle income group and next to it, is Higher Income Group. So it can be said that the people
living in the said area is well satisfied with the infrastructure facilities. But on the other hand there is lots of
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encroachment like slum on the river bed which is necessary to relocate. The TP is truly made for the residential
purpose and it proves its characteristics.
Bunglows 49844.15 24 %
Commercial 4037.19 2%
Educational 2856.72 1%
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Encroachment 34708.40 16 %
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Other Buildings
Commercial
Building Typology Statistics
Commercial cum Residential
Other Types
Educational Total AreaPlacePercentage to
Religious
Building
Encroachments (Sq. Mt.) total
16%
Commercial 4037.19 8% 33%
8%
Commercial 1%cum 3637.04
8% 8% Row Houses
6% Bunglows
Residential 1%
Low Rise
Educational2% 2856.72 6%
High Rise
6%
2%
Religious Place 2956.61 6% Commercial
Commercial cum Residential
Encroachments
10% 34708.40 72 %
Educational
Religious Place
72%
Slum
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Bunglows 49844.15 24 %
30%
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Map 7 Water Flow lines upto 8.0 Mts
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the water level is found up to 9.0 Mts. than scenario will be like Map no. 13 And, if further rise in water level is
found than total area will be flooded.
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Map12
Map 10Water
WaterFlow
Flowlines
linesupto
upto9.0
8.5Mts
Mts
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In the above Map 13, when the water level raise at 9.0 Mts., most of the area in the Town Planning Scheme is
affected by the water. The area which are not affected with the water, It shall be identified as safe zone. The area
which is surrounded by higher elevation, are covered with water pond after relieving from flood. So it is being
compulsory to provide good storm water drainage.
Consideration of ground levels of adjoining TPs are also plays important role as the water can enters from that TPs
and flows back. During the flood, the probability of water enters from adjoining area is higher than it enters from
river directly as the area is protected by the Embankment. It is also important to identifying the area in
submergence during high tide in the river with the help of contour map. The Area has average rise of 8.0 to 8.5 Mts.
from the mean sea level. The flooding pattern can be finding out by considering all the adjoining area contours.
Here all different map shows the area of submergence at different level of water at the time of flood. The flowing
pattern of water and coverage of area is basically depends on, from where it enters. Map No. 14,17 and, 19 shows
the flowing pattern of water with respect to rise of water level at 0.5 Mt. of Interval. In this Condition the scenario
will be like Map No. 15, 16 and, 18. If further rise in the water level is found up to 9.0 Mts. than scenario will be like
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Figure no. 20. And, if further rise in water level is found than total area will be flooded.
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The figure
shows the
flowing pattern
of water when
the water level
rise from 7.0
mts. to 8.0 Mts.
In this condition,
the water can
enters into the
study area only
from the river
side as the
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surrounding
areas’ ground
levels are higher
than that.
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The below figured show the area to be submerged when water level rise up to 8.0 Mts..
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area.
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Figure shows the water flow up to 9.0 Mts. in the study area and covers the whole area.
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Above maps shows the area to be submerged during the different level of water. Based on the above maps, further
it shall be classified based on criticality of the area with respect to flood like Area at low risk, Moderate risk and
High risk. It is stated as below.
These maps give perfect Information about the types of land use at risk at different level of water. The information
is helpful for planning reactive approach for the particular area at the time of flood. The feasibility of the
reservations are also drown out from these maps. It shall be helpful for identifying the Infrastructures at risk of
flood. The maps clarify the above conditions more evidently.
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It is clear that the most of the TP area covers with the Row Houses and Bungalows (Map 5). There are very less
apartments compare to the row houses and bungalows. It means, at the time of flood, Majority of people at risk are
belonging from Middle Income Groups. Most of the encroachments like slum are located in the river bed, where the
ground level is at 7.0 Mts only from mean sea level. Some of the low rise apartments are also at risk of flood as they
have no ground clearance.
The Risk maps show that when the water column raised more than 8.0 Mts., it covers the main road of the TP area.
Due to this the people lost their accessibilities for their daily needs. From the past flood scenario, it is clear that at
the time of flood immediate action taken by the government is to cut down the electricity to secure the people from
man made hazard. The majority of the residential area is under the risk of moderate flood. From the past flood data
it is also seen that no flood had the water column less than 8.0 Mts. So the 80 percent of study area is affected by
the moderate flood.
The municipal corporation had placed the reservation like commercial, Recreational area, public buildings,
educational buildings etc. Some of the reservations like public building are also located in the river bed where
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ground level is only 7.0 Mts. The reservation for the Socially and Economically Backward Class people are located in
Moderate flood risk area. The commercial reservations are allotted in safe zone or low risk area with respect to
flood.
So it is compulsory to carry out flood risk assessment before placing reservation or identification of land use
maps. The reservation allotted for recreational areas in the ground level 7.0 Mts. is very good attempt made by the
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Development authority. But in spite of that some other interventions are also needed to reduce the negative impact
of flood on the living community, which we will discuss in next Chapter.
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The UK guidance notes rely heavily upon the availability of flood plain maps in their sequential approach to
determining the need for flood risk assessments, as the trigger for requesting a flood risk assessment relies on a
preliminary assessment of whether a proposed development lies within the flood plain.
Given the current absence of a national database of such maps, such an approach may not be possible. However, a
flood risk assessment should be carried out wherever it is thought that a proposed development may be at risk of
flooding and/or may lead to an increase in flood risk elsewhere. A range of indicators may be used to suggest that a
site may be at risk of flooding, including:
with little access in the river bed itself by provision of platform/ floating structures;
Identification of areas (using zones) in vicinity of flood protective structures with level of risk identification;
Identification of effect of back water in the area of upstream of any obstructions (either natural {e.g. rock
outcrops} or man-made {e.g. culvert, weir}) with spatial spreads of water in the surrounding areas;
Identification of areas wherein developments may be overlying alluvium strata.
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Even if the proposed development site is located behind existing flood defenses, it is advisable to carry out a flood
risk assessment to ensure that the development could withstand flooding in the event of the flood defense
breaching or being overtopped.
It is recommended that a flood risk assessment is carried out as early as possible in the development planning
process. This is because flood risk issues may have a major impact on the viability, end use, master planning and
design of a development site. If a site is found to be subject to flood risk then ideally it should be left in its
undeveloped state and an alternative location found for the development site. If this is not possible because of
other factors, then the development must be designed carefully to address the flood risk issues.
Ideally, flood risk assessments should be carried out before land is purchased for development, and the materplan
of the proposed development only be created once the site constraints due to flood risk issues are fully understood.
Consultation should be undertaken with the local development planning authority at as early a stage as possible to
ascertain the requirements in relation to flood risk issues.
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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,
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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.
LAND USE
Prohibited Density transfer / Public awareness Locate public facilities
development density bonus campaign outside floodplain
Limit density Preferential taxation Purchase property
Exclude hazardous /
critical land uses
DESIGN OF BUILDING
Elevate site with fill Availability of flood Technical assistance
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SITE/LANDSCAPE
Elevate roads and insurance publications
DESIGN
other infrastructure Workshops for site
Set back from hazard planners / civil
Cluster on least engineers
hazardous portion Technical assistance
Impervious surface of retrofitting
regulations provided at disaster
On-site flood assistance centers
detention / retention after floods
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requirements
Impact assessment
DESIGN OF
Elevation to or above Availability of flood Technical assistance Design public
BUILDINGS
base flood (e.g. 100- insurance publications buildings as leading
year flood) Low-interest loans Workshops for by example
Flood-proofing Tax deferral architects/home
Retrofits of existing builders
buildings Technical assistance
Impact assessment on retrofitting
KNOWLEDGE OF
Mandatory disclosure Free or low-cost Public awareness
HAZARD/MITIGATIO
in real estate technical assistance campaigns
N
transactions Flood warning system
Mandatory Posting of warning
delineation of signs
floodplain areas Provision of
Mandatory information in public
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AREA-WIDE
Peak discharge Flood control
CONTROL OF FLOOD
standards structures
HAZARD
Storm drainage Channel
requirements improvements
Impact fees for flood Watershed treatment
control
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RESILIENCE OF
Subdivision design Vulnerability Design standards on
PUBLIC FACILITIES
standards assessment public buildings
Retrofits
Source : Burby, R.J., Land-use Planning for Flood Hazard Reduction, in: Parker, D.J. (ed.), Floods (2000).
The detailed selection of means to be utilized will depend on the local context in terms of the prevailing socio-
economic, legal, political and cultural conditions, however, a mixture of elements from above-mentioned strategies
is more likely to be successful than only focusing on one of them. For example, regulations brought forward by
Government that prohibit to develop a particular floodplain may collide with local economic or private land owner
interests if not combined with a public awareness campaign on the risks of development in that area, and the
provision of reasonable alternative options to pursue local development aspirations. One of the key considerations
would be how much land is required to pursue a local development agenda and how much of it is located in
hazardous areas. This usually limits the choices considerably.
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Enforcement capacity of the authorities concerned has an impact on the choice of instruments applied. Enforcing
land-use regulations can be a lengthy, complex and resource intensive task. Depending on the prevailing system of
property rights regulations can be challenged on various grounds in courts and this can hamper implementation
considerably or even deny the achievement of the initial intent of the regulation on legal grounds12. This is another
argument why authorities have applied combined instruments to exert control over land-use. The National Flood
Insurance Programme (NFIP) in the United States is a federal program enabling property owners in participating
communities to purchase insurance as protection against flood losses in exchange for State and community
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floodplain regulations that are designed to reduce future flood damages. Other incentives mentioned in Table
include taxes and fees as a tool in land use regulation. Various models of taxation and fees on land and
developments are also applied to provide incentives to preferential land uses and development options, or provide
disincentive to undesirable uses.
It is of crucial importance to adopt a risk-sensitive approach that would increase regulative intervention with
increasing levels of risk, based on different hazard zones and the projected or existing types of development within
each zone. Compared to the simplicity of that statement in theory, the successful practical application is highly
complex.
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Floodplain zoning ordinances constitute an important tool to operationalize a risk-sensitive approach. Floodplain
zoning can be undertaken on the basis of average of past flood data. The most commonly used for land-use
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planning purposes is the 1% average annual exceedance probability. In the United States, for instance, a further
distinction in floodplain zoning ordinances is made between the ‘floodway’ and the ‘floodfringe’ based on floods of
a 1% exceedance probability. As illustrated in Figure , the floodway in this context is referring to the high-risk area
that is kept free from any development to allow floodwater pass through this corridor unobstructed. The level of
risk to determine floodway areas can be based on factors such as the depth and velocity of flood water, duration of
flooding, available flood storage capacity, or the rate of rise of flood water. While in some countries land-use plans
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have legal authority in their own right, floodplain zoning ordinances or similar legally binding instruments are used
elsewhere to enforce land-use planning.
The process of issuing development or planning permits is applied to ensure compliance of planned developments
or changes of land use with the regulatory regime, i.e. in relation to flood management to limit or minimize the
flood risk to the development and the effects of new developments on flood risk elsewhere. Various activities on the
floodplain or activities that have an influence on flood risk can be subject to permission, such as:
Subdivision: the splitting of an existing land parcel into several pieces owned by different owners.
Depending on the type of activity the use of low risk areas such as the ‘flood fringe’ may be acceptable under
certain conditions and enforced during the application process for a planning permit. Certain developments may be
permitted under certain conditions, relating for example to the:
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Restriction on storage and goods and materials that may create pollution or become a floating hazard during
floods;
Land drainage and effluent disposal requirements;
Requirements for access roads or tracks;
Requirement of Elevated Road Embankments
Maximum height and extent of landfill and earthworks, including levees;
Availability of emergency preparedness plans (for example for tourist sites, camping places, hotels etc.); and
Provision of adequate water retention or drainage facilities.
Building standards and codes can play a strategic role in reduction of potential flood damages. They must, however,
be coordinated with floodplain regulations. Building standards can address various structural features of a
development to take into account prevailing flood hazards, such as
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Freeboards above base flood elevation for buildings and essential infrastructure (access roads etc.). For the
provision of the ground floor non-residential, it is compulsory to permit the habitants to raise one floor more
than other part of the vicinity other than flood plan area.
If there is any internal circulating system like roads than it is advisable to provide the kerbing with drain or
providing Bore holes at regular distance of 10 to 15 Mts. to recharge ground water table.
Protection against foundation erosion
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The Ground floor pavement shall be developed with help of permeable paving techniques as shown in the
figure.
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Buildings lies in the areas at moderate risk of flood, should have either high plinth level above 25 year flood
mark or constructed on columns or stilts, with ground area left for the unimportant uses;
The development permission shall be in such pattern (i.e. location of types of buildings) that it gives priority
to survive human being from flood water. Means Row houses or bungalows can be located on higher ground
elevation and Apartments can be located on lower contour site.
Limit enclosure for parts of the building below the regulatory flood level (e.g. put houses on stilts)
Orientation of the building to least obstruct flood flows
Various measures of wet and dry flood proofing (backflow valves, waterproofing measures to opening like
windows and doors, elevated electricity features, water proof storage of oil and other hazardous materials
etc.)
Compensation for storage losses due to land fill
Building standards and codes tend to be under a stronger local inspection regime than floodplain regulations.
Therefore compliance is more likely to be enforced. Therefore, it is advisable to consider building codes as crucial
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elements of flood damage reduction strategies when reforming the flood management system. Examples exist
where reform to building codes has been undertaken through dedicated flood management legislation.
Coordination of such legislation must be undertaken at a higher administrative scale, i.e. national/federal or state
level.
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Any proposed drainage designs must conform to the relevant specifications outlined by local body for the
flood prone areas and fulfilled all the installation standards;
Install "check valves" in sewer traps to prevent flood water from backing up into the drains of your home
during the flood.
The proposals must address the cumulative impact on infrastructure capacity of incremental growth of
impermeable surfaces by not increasing the quantity and rate of surface water run-off from any site;
For large developments where there is an intention to separate the development into zones, which are to be
constructed at different stages, or by different developers, a drainage master plan covering the whole area of
development is submitted.
A Drainage Impact Assessment should be undertaken by a competent professional. It is recommended that a
DIA should be carried out under the direction of a member of the relevant chartered professional institution,
with experience of drainage impact assessment and management.
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In view of the dilemma faced by land use planners in dealing with flood hazards multi-functional land-uses play an
important role. In countries that face the scarcity of land already for decades and for urban planners this concept is
already widely applied. It can, however, be observed that the concept is gaining importance even in countries that
previously were not using this approach.
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Examples of widely applied multi-functional land uses include the use of water storage areas for recreational (non-
residential) purposes, such as outdoor sports facilities, parks and nature reserves.
Flood adapted housing is also used increasingly, such as floating structures or elevated structures on stilts. In
Southeast Asia such approach is common place for long, yet in the countries that had adopted a strict flood defense
policy which worked on the premise that flooding could be prevented; such practices had not been common.
Similarly, recession agriculture is commonplace in various flood prone developing countries, using the floodplain
for agriculture in the flood-free months. It is also advisable to plant heavy forest trees in flood prone areas to retard
the velocity of the water during flood.
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Conclusion
CONCLUSION
Complexity of flood risk evolution process requires a clear understanding of the construct of the typology of various
components of flood risks and the factors that mitigate or abate them. Many sectoral development processes have
profound influence on their management. The complex interaction between development processes and flood risk
origin requires a clear conceptual framework which is supported by appropriate organizational and institutional
mechanisms to develop and implement surface water management plans.
A report on the methodologies used, and findings of, the flood risk assessment should be submitted to the local
development planning authority for the newly merged area of the city which is going to be develop in future. This
should provide sufficient information that the local development planning authority can make an informed decision
about the appropriateness of the proposed development in flood risk terms.
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In order to ensure future development is sustainable, it is essential that the flood risks to, and caused by,
development are assessed and managed in an appropriate manner. As the greatest opportunity for managing such
risks lies with the planning and design of new developments before they are constructed, it is vital that the flood
risk assessment process is an integral part of planning applications for any development that has the potential to
increase flood risk. New developments may increase flood risk in a number of ways, but use of appropriate scientific
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tools to aid planning and design of development sites may enable the engineer to avoid unacceptable increases in
flood risk. This study provides one of the flood risk assessment process.
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REFERENCES
References
1. “THE GUJARAT DISASTER MANAGEMENT ACT ,2003” ; gujarat act no. 20, 2003
2. Anup Karanth (Project Coordinator) ,“REPORT ON VULNERABILITY AND RISK PROFILE OF INDIA” ; Urban
3. “TOWARDS THE DISASTER RESILIENT COMMUNITY IN GUJARAT”; undp disaster risk management
4. A GLOBAL REPORT ON “REDUCING DISASTER RISK, A CHALLENGE FOR DEVELOPMENT” ; UNDP (INDIA)
5. Devasia K. J. (District Project Officer), (15 MAY, 2005), “ DISTRICT DISASTER MANAGEMENT PLAN - NORTH
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6. “PLANNING AND WARNING TOOLS FOR FLOOD DISASTER MANAGEMENT IN LAGOS MEGA CITY”;
7. NMSI Arambepola, Gabrielle Iglesias, “EFFECTIVE STRATEGIES FOR URBAN FLOOD RISK MANAGEMENT”,
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8. “ DISASTER MANAGEMENT IN INDIA - A STATUS REPORT”; National Disaster management division, Ministry
9. www.wikipedia.com/Disaster
10. USGS, “FLOOD RISK ASSESSMENT”, USGS Water Resources Investigations Report on Flood-Frequency Prediction
11. FLOOD RISK ASSESSMENT AND MANAGEMENT FOR THE THAMES ESTUARIES
12. James Lancaster & Clive Marshall (2003), “FLOOD RISK ASSESSMENT FOR DEVELOPMENT PROPOSALS” , National
13. Ashford Borough Council and the Environment Agency “FLOOD RISK ASSESSMENT ASHFORD TOWN CENTRE
14. Www.Suratclimatechange.Org
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15. DR. JAYANTILAL N. PATEL ,PRASIT G. AGNIHOTRI (April – 2008), “PREPARATION OF FLOOD REDUCTION PLAN
FOR SURAT CITY AND SURROUNDING REGION (INDIA)” , Vol – 3, Issue – 2, Surat, Gujarat, India
16. London resilience team, “LONDON FLOOD STRATEGIC RESPONSE PLAN”, Issue – 1, March – 2007
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