Technical Notes
Indisdata - Disaster Database
The State of Tamil Nadu was the most affected in terms of human, property loss because
of the Indian Ocean Tsunami of 26th December 2004. Not just Tsunami, but the state also
faces severe crisis every year by means of seasonal floods. To have a holistic approach
towards long term preparedness and mitigation of disasters, this database has been
created. This database gives the trends, patterns and seasonality of disasters affecting the
state.
The DesInventar (herein used as Indisdata) methodology is a cost effective system used
in Latin American countries to systematically record time, place, and effects of disasters
on its occurrence. The methodology uses Indisdata software, a web based simple tool to
capture the data and analysis it to create charts, tables, graphs for decision making.
The MoU was signed in January 2006 between United Nation Development Program
(UNDP) and Government of Tamil Nadu(GoTN) represented by the relief commissioner
who is also the Special Commissioner and commissioner of Revenue Administration (SC
& CRA) of the state. A database of disasters was created and the following major tasks
were completed
1) Disaster data for the period 1975-2007 was collected from authentic government
sources recommended by the SC&CRA office
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Revenue Department ( Districts collectorates)
India Meteorological Department
Fire and Rescue Services
Forest Department
Department of Geology and Mining
Medical and Rural Health Services
Water Supply and Drainage Board
2) The data was collected at sub district level ( 30 districts, 201 Sub districts -2007 )
3) The collected data in the prescribed form was compiled and properly scrutinized
before data entry.
The system was hosted online at URL www.indisdata-tn.gov.in in government domain
with 13,614 records as on 31st December 2007. For this report, records from records from
1998-2006 have been taken.
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Definitions of Key Terms Used in Indisdata
Accident: Automobile, rail, aircraft or navigation accidents. Includes transportation accidents
generating spills or leaks of harmful substances, regardless of the cause.
Alluvium: Torrential water flows dragging large amounts of solid material (pebbles, stones, and
rock blocks) common in dry regions or river beds produced by heavy rain.
Animal attack: Attacks by elephants or other wild animals, including snake bites Plague
Proliferation of insects or animal pests affecting communities, agriculture, cattle or stored perishable
goods; for example, rats, locusts, African bees, etc.
Biological Event: Destruction of biological species for known or unknown reasons. In the end,
these events may be associated to pollution or drastic changes in environmental parameters.
Disasters from insects or animal pests affecting communities, cattle or stored perishable goods
should be reported under Plague.
Boat Capsize: Overturning of a boat due to hitting the water-bed or due to sea-disturbances.
Coastal erosion: Variations of the coast line and/or maritime zones near the coast. Includes
formation and destruction of islands, beaches and sand banks and erosion of cliffs affecting
populations, navigation, etc.
Cold Wave: Lowering of atmospheric average temperature well below the averages of a region,
with effects on human populations, crops, properties and services
Cyclones: High speed whirling winds moving in a circular path (of about 100-300 km diameter) in
an anti clockwise direction around an extremely low pressure area at the centre. Strong whirling
winds accompanied by rain. They are originated in the Bay of Bengal.
Disaster: Disaster is defined as the set of effects caused by an event (whether natural or not) on
human lives and economic infrastructure on a geographical unit of minimum resolution.
Drought: Unusually dry season, without rain or with shortage of rain. As a whole, these are long
periods (months and even years).
Earthquake: All movements in the earth's crust causing any type of damage or negative effect on
communities or properties. The event includes terms such as earth tremor, earthquake and
vibration.
Epidemic: Disease attacking many individuals in a community during short terms (days, weeks,
months maximum), such as cholera, typhoid, bubonic plague etc.
Eruption – Volcanic: Volcanic eruption with disastrous effects: eruption and emission of gas and
ashes; stone falls (pyroclast), flows of lava, etc. This event includes eruption of sludge volcanoes
found in some Caribbean regions
Event: Event is defined by DesInventar as a phenomenon, whether natural or not, which, once
triggered, produces adverse effects on human lives, health and/or social and economic
infrastructures.
Explosion: Explosions of any type
Fire: Urban or industrial, but not including forest fires. Due to natural phenomena such as lightning,
earthquakes, or due to accidents, technology failure etc.
Flash-Flood: The sudden overflowing of a river; or violent water flow in a river or stream; or
unexpected violent water flow on drainage path or land. Flash floods can be caused by rain; a
reservoir dam overflowing / bursting / breaching; or abundant landslides on a watershed or basin.
Flash-floods usually carry tree trunks and/or fine to bulky sediment.
Forest fire: Forest fire includes wild fire, bush fire or grass fire. The event includes all open-air fires
in forests, natural and artificial forests, plains, etc.
Frost: Temperature low enough to cause freezing with damaging effects on population, crops,
properties and services.
Hailstorm: Frozen raindrops that fall violently in the form of hard pellets. Hailstones. Precipitation of
hail.
Heat Wave: Rise of atmospheric average temperature well above the averages of a region, with
effects on human populations, crops, properties and services.
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Landslide: All mass movements other than surface erosion 'of a hillside. This event includes terms
such as precipitation of earth, settling, horizontal land' thrust, mass movement, displacement,
subsidence, collapse of caves or mines, rock falls (slow or quick), detachment of soil masses or
rocks on watersheds or hillsides.
Leak, Oil Spill: Leak of harmful liquid, solid or gas substances, toxic/lethal chemicals, explosives
and other hazardous materials, whether radioactive or not, generated by technological accidents,
human fault or transportation accidents. Oil spills in sea from vessels / crafts.
Lightning (Thunderstorm): Electrical Storm: concentration of atmospheric static discharges
(lightning), with effects on people, cattle, domestic properties, infrastructure (mains, for example,
causing blackouts), and industries. It is different from "storm" in that thunderstorms are not
accompanied by rain and gusty winds.
Panic: Panic or mass hysteria among people concentrated in a certain place (stadiums, theatres,
etc.) that can kill or injure them, and cause physical damage. Includes panicky situations caused by
early warnings about incoming events. An example is the panicky situation created by possibility of
elephant attack during a procession with hundreds of elephants where thousands of people are
gathered along the route.
Pollution: Concentration of polluting substances in the air, water (surface/ground) or soils, at levels
harmful to human health, crops or animal species.
Rain: Precipitation, including punctual, persistent or torrential rain, or rain exceeding the average
rainfall of the specific region; also unusually long rain periods. Rain includes terms such as
downpour, cloudburst, heavy shower, deluge, persistent drizzle, squalls, etc.
Sedimentation: Deposits of solid material on hillsides and river beds produced by mass
movements or surface erosion with damages on crops, utilities or other infrastructure. Soil Erosion
Washing away of soil down the surface of hill slopes or mass movements due to storm water flow
during intense rains. This can cause sedimentation in streams / rivers and areas at the toe of the
hills.
Snowfall: Anomalous fall and accumulation of snow, especially when it occurs in zones not subject
to seasonal changes. This term refers to events where precipitation exceeds the average multiannual values, causing especially serious effects.
Storm/Gale: Rain accompanied by strong winds and/or lightning. There is no difference between
"storm" and "gale". Gale is a very strong wind. The term is synonymous with gust.
Structural Collapse: Damages or collapse of any type of structure for reasons such as excess
weight in public places, bridges, etc. This event includes damage that, although not taking the
structures to the point of collapse, does make them Unusable. Damages in structures caused by
natural phenomena are reported as an effect of these phenomena.
Surge: On land - This can be a surge of water mass due to overflowing or breach of a reservoir
dam. This would be synonymous with flash floods. Sea Surge - Sea tides breaking on the shore and
flooding the coastal areas. Can result in erosion of beaches and sand banks.
Tidal Wave: Great sea waves breaking on the shore. Includes waves caused by hurricanes, gales
or storms (other than tsunami or seaquake), by rise of average sea level during the phenomenon
"EI Nino".
Tornado: Tornados are winds whirling around a small area of extremely low pressure, usually
characterized by a dark funnel shaped cloud causing damage along its path; usually without rain or
little rain. The term is synonymous with whirlwind.
Tsunami: The term is applied only to waves generated by under-sea movements (caused by
earthquakes, volcanic eruptions or under-sea landslides), breaking on the shore
Urban Flood: Storm water that gets collected in city or urban areas after heavy rains due to
blocking or under capacity of storm water drains.
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Nature of Data for Orissa
(a) The natural hazard profile of the state has been prepared based on the data collected
from the govt. and des-Inventar sources for a period of 10 years from 1998 to 2007
because of its completeness and consistency.
(b) The parameters which are considered to be more significant and relevant for use in
this study are population affected, houses destroyed (which are mostly private), property
loss (mostly institutional) and human death.
(c) The natural hazards which are mostly important in terms of their impact on the state
can be grouped into two categories i.e. Climatic hazards (Flood, Cyclone, Lightning &
Heat waves ) and Others hazards such as Fire & Epidemics. Although many parts of the
state suffer from the drought situations very frequently, the data relating to droughts is
not matching with the other hazards for which it has not been used in this analysis.
(d) Out of the ten years of the data base used in this study, data for the period 1998 to
2000 is from the Des-Inventar and from 2001 to 2007 is from the Government of Orissa
sources.
Data Definitions in Tamil Nadu
Data card1: A data card corresponds to the damage and loss that have occurred in a
location as result of medium or large scale disaster event.
Events: Event is defined by DesInventar as a phenomenon, whether natural or not,
which, once triggered, produces adverse effects on human lives, health and/or social and
economic infrastructures.
Definition of "Disaster": Disaster is defined as the set of effects caused by an event
(whether natural or not) on human lives and economic infrastructure on a geographical
unit of minimum resolution.
Date (start and end): the date when the disaster occurred and ended (Year/Month/Date).
Killed: Persons confirmed dead and persons missing and presumed dead.
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Injured: People suffering from physical injuries, trauma or an illness requiring
immediate medical treatment as a direct result of a disaster.
Homeless: People needing immediate assistance to shelter.
Affected: People requiring immediate assistance during a period of emergency; it can
also include displaced or evacuated people.
Total affected: Sum of injured, homeless and affected.
Victims: Number of persons whose individual or collective property and/or services have
suffered serious damage directly associated to the event. For example, total or partial
destruction of homes and property; loss of crops and/or warehouses, etc. This group also
includes evacuated or resettled persons,
Estimated damage: Several institutions have developed methodologies to quantify these
losses in their specific domain. However, there is no standard procedure to determine a
global figure for economic impact. Estimated damage is given in US dollars and or in
Indian Rupees.
Evacuated: Number of persons temporarily evacuated from their homes. If the
information is available by family, the number of persons must be estimated based on
indicators available.
Relocated: Number of persons who have been moved from their homes to new
permanent sites. If the information is available by family, the number of persons must be
estimated based on indicators available.
Missing people: Number of persons whose whereabouts as from the effects of the
disaster are unknown. It includes people presumed dead without physical evidence. Data
on dead and missing persons are mutually exclusive; therefore, avoid grouping them.
Destroyed Houses: Houses that have collapsed, or have been swept, submerged or
damaged in such a manner that they are not habitable.
Affected Houses : Number of houses that suffered minor damage other then structural or
architectural, and continue to be habitable, although requiring basic repairs and cleaning.
Roads - Mts. : Extension in meters of road networks destroyed and/or unfit for use.
Hectares : Crop, pasture or forest areas destroyed.
Livestock : Number of animals lost.
Education Centers : Number of nurseries, schools, universities, training centers, etc that
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were destroyed and/or affected.
Hospitals ; Number of local and regional health centers, clinics and hospitals.
Transport: Road networks, railways, transport terminals, airports, river and seaports.
Agricultural : Crops, farms, pasture zones.
Communications : Telephone plants and networks, radio and television stations, mail
and public information offices.
Power: Dams, substations, transmission lines, generation plants, processing plants, fuel
deposits, oil and gas lines.
Education: All related to this sector: nurseries, schools, universities, training centers, etc.
Rescue Departments ; Fire departments, Civil Defense, Red Cross and public order
entities.
Water Supply Systems : Intakes, treatment plants, aqueducts and canals conducting
drinking water.
Sewerage:
Networks for disposal of waste and/or rain water; treatment plants.
Industry: Industries of all types and sizes, including agricultural and livestock industries.
Health: Local and regional health centers, clinics, hospitals.
Losses in Rupees : Amount of direct losses in present value (local Currency)
Disasters identified by the High Powered Committee
I
Water and Climate related disasters
1. Floods and Drainage Management
2. Cyclones
3. Tornadoes and Hurricanes
4. Hailstorm
5. Cloud Burst
6. Heat Wave and Cold Wave
7. Snow Avalanches
8. Droughts
9. Sea Erosion
10. Thunder and Lighting
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II
Geologically related disasters
1.
2.
3.
4.
Landslides and Mudflows
Earthquakes
Dam Failures / Dam Bursts
Mine Fires
III Chemical, Industrial and Nuclear related disasters
1. Chemical and Industrial Disasters
2. Nuclear Disasters
IV Accident related disasters
1. Forest Fires
2. Urban Fires
3. Mine Flooding
4. Oil Spill
5. Major Building Collapse
6. Serial Bomb Blasts
7. Festival Disasters and Fires
8. Electrical Disasters and Fires
9. Air, Road and Rail Accidents
10. Boat Capsizing
11. Village Fire
V Biologically related disasters
1.
2.
3.
4.
Biological Disaster and Epidemics
Pest Attacks
Cattle Epidemics
Food Poisoning
Important Terminologies
The profile of the natural hazards in Orissa state has been prepared with the following
understanding of the commonly used terminologies dealing with the natural hazards &
disasters:
(a) Natural hazards are natural processes or phenomena occurring in the biosphere that
may constitute a damaging event.
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(b) Natural Disaster is a serious disruption triggered by a natural hazard causing human,
material, economic or environmental losses, which exceeds the ability of those affected
people to cope. It is understood to be an outcome of natural hazards and human
vulnerability coming together, the coping capability of society influences, the extent and
severity of damages received.
(c) Human Vulnerability is a human condition or process resulting from physical,
social, economic and environmental factors, which determine the likelihood and scale of
damage from the impact of a given hazard.
(d) Risk is the probability of harmful consequences, or expected loss of lives, people
injured, property, livelihoods, economic activity disrupted (or environment damaged)
resulting from interactions between natural or human induced hazards and vulnerable
conditions. Risk is conventionally expressed by the equation:
Risk = Hazards * Vulnerability
(e) Physical exposure implies element at risk, an inventory of those people exposed to a
hazard. The important parameters used in this report relating to profiling of the natural
hazards are exposed population, human causality, houses destroyed and property
damaged. These data are collected from the government official records from the
districts which are compiled at that level after being collected from the blocks / tehsils
and from their respective villages. Tehsil/ block in India is a level of administrative unit
below the district and above the village. India is divided into states and states into
districts.
(f) Exposed population data relates to the number of people exposed, collected from the
villages aggregated for the whole block and than at the district level. Government uses
this data to demarcate the hazard prone areas of the block/tehsil and the district and
subsequently for providing relief and taking rehabilitation measures.
(g) Human causality refers to the number of people dead due to the natural hazards. This
data is meticulously collected at the village level and then compiled for the block/tehsil
and district level for sanctioning ex-gratia aid to the families where there has been a
causality.
(h) Houses destroyed imply complete demolition of the houses or houses completely
washed away due to a natural hazard. The tehsil revenue authorities keep records of
houses destroyed. This data is collected at the village level and then compiled at tehsil
and the district level. The records are maintained carefully for sanctioning of housing
assistance to those whose houses are destroyed by a particular disaster.
(i) Loss of property implies estimated loss to the public institutions and public properties
in monetary terms because of the damage caused due to disaster. This damage is assessed
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by the revenue deptartment. Revenue inspector compiles such a data for the group of
villages for which he/she is in charge taking information from the concerned offices. This
damage is recorded as the property loss due to a natural hazard given in Rupees. This
gives a picture of the magnitude of loss of public properties in the affected area.
(j) Impact of disasters is measured in four important parameters i.e. exposed population,
human causality, destroyed houses and damage to property may be considered most
useful as far as the impact of the disasters is concerned for this purpose.
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Disasters Identified by UNDP for Analysis in Tamil Nadu
Sl.No
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
Event
Data Cards
Accident
Cloud burst
Cold
Cyclone
Drought
Earthquake
Epidemic
Eruption
Explosion
Fire
Flash flood
Flood
Forest fire
Frost
Hailstorm
Heat wave
Hurricane
Landslide
Leak
Lighting
Liquefaction
Other
Rains
Sea erosion
Spate
Storm
Strong wind
Structure
Tidal wave
Tsunami
449
1
1
65
233
4
170
1
89
5902
111
3138
811
1
4
2
1
42
10
305
3
57
1833
4
5
2
14
210
6
84
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Notes
1
This system of reporting of disaster occurrence through data cards has one major limitation. The
reporting unit is taluka and hence each taluka would report an incidence of disaster. In case of a major
or extensive disaster, such as cyclone or floods that would impact number of talukas at a time, the
same disaster would be reported from all the impacted talukas increasing the number of occurrences
when, in fact, it is just one disaster occurrence.
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