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3-3. Cases of Disaster Countermeasures
3-3-1. India Gujarat Earthquake
Tasks in Emergency Relief to Restoration: One Month from West India Earthquake1) Introduction
On January 26 at 8:46 am (Indian Standard Time, time difference with Japan: 31/2 hours), the Indian
Province of Gujarat, situated at the western edge of India, was hit by an earthquake measuring 6.9 on
the Richter scale. The epicenter was 20 km northeast of the city of Bhuj in Gujarat. Damage wascentered on the Kachcch district. High-rise apartments also collapsed in Ahmedabad, the largest city in
Gujarat 300 km from the epicenter. The death toll stands at 20,717 as of March 7.
The director of the ADRC, Yujiro Ogawa, visited the site from January 26 (just one month from theearthquake) to March 6 as part of the Japanese government’s “commission to investigate the reasons for
specialists being requested to support restoration and rehabilitation for West India earthquake damage”.
Based on the findings of the survey, the state of Gujarat and future tasks as of one month after theearthquake is introduced below.
2) City of Bhuj One Month Later
We flew from Deli to Ahmedabad andentered the city of Bhuj by car. Bhuj has apopulation of about 70000, and markets
along the roads bustled with activity. In theurban area, there was a mixture ofcompletely
destroyedbuildings
andsemi-intact ones. There was not one buildingthat escaped damage. Three tent villages forvictims were set up around the city, in which
many of the residents of Bhuj lived. Some
lived on the streets, and there were also
many shops that were open for business(Photo 1). We were also able to stay at oneof the affected hotels in the city, thoughfearing after-tremors.
Photo 1
The central hospital which had 281 beds had collapsed from the earthquake. Of the 176 patients who
had been staying at the hospital on the day of the earthquake, 160 had died. Currently, they have set up atemporary hospital to continue operations (Photos 2 and 3).

Photo 3

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The Health Care Center had also been affected,
though it was a smaller building. They had also
built a temporary building to continue operations.
There was a water supply to the city (Photo 4).
The whole province of Gujarat is frequently hit bycyclones, but at the same time, its dry season issevere. With the normal water supply system,
water is supplied from a well to each household bya water supply vehicle. This water is then kept in awater storage tank and used. During the dry season,some wells dry out, and residents receive waterfrom distant wells. Though the earthquake
Photo 4
damaged the wells, because the water supply
system for use in the dry season has been
expanded, there has been no water shortage.
Schools have also reopened. Though there are noschool buildings, lessons are held on dirt floors
using sheets as partitions. The same was seen inmunicipal offices. Work was done in partitioned
spaces. (Photo 5)

3) Damage of Small Infrastructures.
As we traveled from Ahmedabad to Bhuj on road,the abutments of a bridge across the large river
flowing out to the Sea of Arabia had broken, andthose of several bridges were damaged (Photo 6).
However there was no damage, etc. to roadshoulders or top-heavy water towers (Photo 7).

Photo 5Photo 6

4) Urgent Tasks
The current issue at the damaged sites is how to cope withthe monsoon season, which starts in June. As mentioned
earlier, this district is prone to dry weather and rain occurs
mostly during the rainy season. As most of the victims live Photo 7
in tents, and most hospitals, schools, and administrative
offices operate on dirt floor rooms separated by sheets or boards, it is evident that these will not be able
to endure the monsoon rain. In damaged buildings that are barely livable, rain leaking in from damaged

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portions cannot be avoided. This monsoon season is just a few months away. The homes partially orcompletely damaged by this earthquake totaled 900,000, and it is clearly difficult to supply temporary
housings in a few months. Mornings and nights at the site in early March tend to get chilly enough toneed a sweater. The weather becomes warmer from April to May with temperatures rising one degree
every day. This will mean that victims will again lose homes. Aggravating hygiene conditions is anotherconcern. In this sense, this disaster started with the earthquake and is still ongoing with the imminent
arrival of a monsoon, though emergency relief seems to have come to an end.

5) Long Term Tasks
The provision of emergency temporary housing for victims to cope with the monsoon season is anurgent task. On the other hand, some of the long-term restoration and disaster management tasks in the
future, which must be addressed are as follows:
6) Reinforcement of Earthquake-Resistance of Buildings
The conventional housing in the photographs evidently have poor resistance to earthquake. Thesebuildings are by local masonry, and basically at low costs using local technology and materials. It istherefore unrealistic to expect high earthquake-resistance in these buildings. Instead, building
reinforcement using techniques available in the area is required. Since Indian technology is said to beadvanced, the solution to this problem lies in educating the masonry.
Regarding RC structures (Photo 8) or engineering structures, according to Professor Emeritus Arya of
Roorkee
University,
buildings
built
according to construction standards suffer
slight damage. The greatest problem in thecurrent situation is that those standards are
not observed. Local municipals are required
to observe building standards whenconstructing, but construction regulations
are not enforced by the central andprovincial governments. The reform of laws
andsystems
relatedtobuilding
standards-application of building standards
to all buildings, punitive system forviolationsofbuilding
standards,
clarification of the responsibilities ofarchitects and construction supervisors, etc.
is thus a long-term task.
Photo 87) Reconstruction of City
In the center of the city of Bhuj, there is an old town of about 2 km2 surrounded by walls. This central
area is concentrated with old buildings and 5 to 6 story buildings (Photo 9) and has narrow roads thatlook like a maze running through it. This town was particularly suffered damage from the earthquake.
Though the rubble of most of the main roads has been cleared, the inside of the town remains untouched(Photo 10). Naturally, the debris of buildings themselves has yet to be cleared. The problem is that there
seems to be no apparent reconstruction plan for this old town. The Gujarat Province Kachcch District
government office in charge of this project is planning to move all the residents of the town outside, but
the residents are apparently opposing this plan. Furthermore, though all the buildings in the town havebeen damaged in one form or another, people are still living and running barbershops and others inbuildings that escaped collapse. There are even banks operating in these buildings. Because thereconstruction plan remains vague, plans to clear the rubble in the town and all other urban
reconstruction plans have not shown much progress. Anjar, another town about 45 km southeast from
Bhuj, was also severely damaged by the earthquake. It was equally damaged in the 1957 earthquake.
During the 1957 earthquake, mass relocation of the residents had been planned, but apparently theresidents ignored this plan and resumed living in their former homes. The government was unable toimplement some kind of measure to rehabilitate the residents in a disaster-managed city due to theirliving there illegally, and at the same time, the residents were unable to receive any aid. The town thus35

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became frail and weak, and suffered the same consequence 44 years later in the Gujarat earthquake.
Earthquakes are recurring phenomena. In this area, earthquakes occur approximately every 50 years.
Efforts to apply disaster experience and prevent the same thing from repeating are vital. Though not a
problem that can be resolved immediately, urban planning that takes into account disaster reduction
must be undertaken urgently. This may be a task, which Japan can support from its own experience.

Photo 9Photo 10

3-3-2. CYCLONE WARNING SYSTEM IN BANGLADESH
Bangladesh Meteorological Department (BMD) is entrusted with all sorts of weather forecasting.
Weather warning system came into being historically through evolution in order to mitigate suffering ofpeople. Cyclone warning system is the well-known warning system in Bangladesh. Besides there areother warnings such as heavy rainfall warnings, squall warning, hail warning, fog warning etc.

1) Tropical Cyclone season in Bangladesh
Mid March to May and mid September to mid December are cyclone season in Bangladesh.

2) Task of Issuing Tropical Cyclone Warning
Storm Warning Center (SWC) of Bangladesh Meteorological Department (BMD) is responsible for theissuance of warning for the tropical cyclone and all kinds of weather warning and forecast. During thecyclone season, SWC keeps a very watchful eye on such situations for issuing timely cyclone warning
to minimize the loss of life and properties.

3) Work of Timely Detection and Warning
The general task of SWC is to detect of the cyclonic storm in the Bay of Bengal and issuance of timely
warning. The cyclone information issued by the SWC requires meteorologist detect and monitor
cyclones from the formation till its landfall and forecast the cyclone’s future track. Modern technology
has provided the means of early detection and constant tracking. Although more objective methods areunder development, forecast and issuance of warning still depends upon the experience of the
Meteorologists.

4) Standing Orders for Cyclone:
There are standing orders for cyclones to ensure that all concerned Ministries / Divisions / Department /Agencies are able to discharge their functions in a speedy and systematic manner, as time and speed of36

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action are vital to handle the situation efficiently.
There are four stages of actions:(1) Alert Stage (Signal No.1, 2,3 and 4)(2) Warning Stage (Signal No 4)(3) Disaster Stage (Signal No.5, 6,7, 8,9,10)(4) Post Disaster Stage (Signal Immediately after the cyclone till normalcy is attained)(1) Alert Stage:
Besides normal function, Bangladesh Meteorological Department (BMD) ensures the following:a) Shall issue early warning for cyclone as early as possible between 24 and 36 hours ahead assoon as depression forms in the Bay of Bengal.
b) Shall inform the Cyclone Preparedness Program (CPP) over the telephone/FAX about the
depression so as to allow CPP to take appropriate actions including dissemination of information
to concerned Senior Officials of Ministry Of Disaster Management and Relief.
c) Shall issue alert messages on Telephone/FAX to the concerned officials under the code address“Whirl Wind”d) Shall issue suitable special weather bulletins to Bangladesh Betar (Radio) and the Bangladesh
Television (BTV) to broadcast and telecast respectively from all stations and also to the nationalpress for the public benefit. Adequate and constant coordination for broadcast and telecast
beyond normal transmission hours will be established between the Meteorological Department
and Bangladesh Betar(Radio) and Bangladesh Television(BTV) as soon as signal No.3 ishoisted.
e) Shall pass special Weather Bulletins to the control room of Ministry of Disaster Management& Relief, Disaster Management Bureau (DMB), Directorate of Relief and Rehabilitation,
Cyclone Preparedness program(CPP) and Bangladesh Red Crescent Society(BRCS) for taking
necessary action.

(2) Warning and Disaster Stage
1. Shall issue warning message for the following stages:a) Warning: 24 hours in advanceb) Danger: Minimum 18 hours in Advancec) Great Danger : Minimum 10 hours in Advance2. Shall include the following information in warning messages:a) Position of Stormb) Direction and rate of movementc) Area likely to be affected specifying Upazillas of the district if possibled) Approximate time of commencement of gale winds (speed more than 32 mph or 52 km/hr.
e) Maximum wind speed expectedf) Storm surge/tide of approximate height and the areas likely to be affected
3. In case of Danger, warning, messages shall be issued telegraphically to the Secretariats and officialsof concerned ministries/divisions/departments under code address “Hurricane”. In case of Great Danger,
warning message shall have to be disseminated telegraphically to concerned officials of local
administration under code address “Typhoon”. Separate appropriate message shall also be issued
telegraphically to the official concerned under code addresses “Water ways” and “Authority.”
4. Shall issue warning message through FAX to Bangladesh Betar(Radio) and Bangladesh
Television(BTV) to broadcast and telecast respectively from all stations as given below:

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■□ ADRC Annual Report 2000a) Early Warning
Immediately on receipt, if the Radio station is operating and subsequently at
645,1210,1755 and 2325 hours BST.
b) Warning Immediately on receipt and every one-hour there after.
c) Danger/Great Danger: Frequently (Danger signal every 30 minutes and the great danger signals
every 15 minutes without any break) or as advised by the Metrological Department.
5. Pass on warning messages to control rooms of the Ministry of Disaster Management and Relief,
Directorate of Relief and Rehabilitation, Cyclone Preparedness Program (CPP) and Bangladesh Red
Crescent Society (BRCS).
(3) Post Disaster Stage:a) Evaluate the impact of the cyclone and its conformity with the warning givenb) Collect data from the devastating area for research purposec) Evaluate opinion of the people of the area about signals issued

Warning Signal for Maritime Ports
Signal
1.Distant Cautionary Signal No.1

Meanings
1.There is region of Squally weather in the distant sea where a storm may form

2.Distant Warning Signal No.2
3.Local Cautionary Signal No.3
4.Local warning Signal No.4

2.A storm has formed in the Distant Area
3.The port is threatened by squally weather
4.The port is threatened by a storm but it doesn’t appear that the danger is as yet
sufficiently
5.The port will experience severe weather from a storm
6.The port will experience severe weather from a storm of slight or moderateintensity that is expected to cross the coast to the north of the port of Chittagong
or Cox Bazar and to the west of the port of Mongla.

5.Danger Signal 5
6.Danger Signal No. 6

7.Danger Signal 7
8.Great Danger Signal No.8

9.Great Danger Signal No.9

10. Great Danger Signal No.10
11.Failure of Communication No.11

7.The port will experience severe weather from a storm of light or moderateintensity that is expected to cross over or near the port.
The port will experience severe weather from a storm of great intensity that is
expected to cross the coast to the south of the port of Chittagong or Cox Bazar
and to the east of the port of Mangla.
The port will experience severe weather from a storm of great intensity that is
expected to cross the coast to the north of the port of Chittagong or Cox Bazar
and to the west of the port of Mangla
The port will experience severe weather from a storm of great intensity that is
expected to cross over or near the port.
Communication with the Meteorological Warning Center have broken down

Signal for Inland River ports
Signal1.Cautionary Signal No. 1
2.Warning Signal No.2
3.Danger Signal No.3
4.Great Danger Signal No.4

Meaning
1.The Area is threatened by squally winds of transient nature
2.A storm is likely to strike the area(Vessels of 65 feet and under in length are
to seek shelter immediately)
3.A storm will strike the area (all vessel will seek shelter immediately)
4.A violent storm will soon strike the area (all vessels will take shelter
immediately)

It is observed that death tolls and damage to properties have been reduced day by day and is now at
minimum stage. It is mentioned that timely accurate forecast and its implementation is appreciated allover the world. An international award “Smith Tumsuroch” was given jointly to Bangladesh
Meteorological Department (BMD) and Cyclone Preparedness Program(CPP) in 1998.The role playedby CPP are highly appreciated and praise worthy. CPP will continue their efforts to minimize the loss oflife and properties in the days to come in future.

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Besides these signals/warnings, there are some warning also e.g Kalbaishakhi Squall warning, Aviation
Warning, heavy rainfall warning, fog warning, cold and heat warning. A brief description is given
below:
1. Kalbaishakhi Squall Warning:
Under certain synoptic situation when meteorologists expect wind speed preceded 60 kph or more , thenBMD issues Kalbaishakhi squall warning over vulnerable regions.
2. Cold wave Warning:
When minimum temperature comes down below 8-10 degree Celsius, mild cold wave, 6-8 degree
Celsius, moderate cold wave and 4-6 degree Celsius, severe cold wave occurs. In these cases, BMD
issues cold wave warning depending upon its intensity and duration.
3. Fog Warning:
In presence of thin/thick fog and surface visibility reduces 3000m or less, then BMD issues fog warning
for river basins and its adjoining land areas and also for the airports for smoth running of transports andaircraft.
4. Heavy Rainfall Warning:
During Cyclone, monsoon depression or strong monsoon if excessive rainfall is likely to occur withinshort period, heavy down pour may paralyze normal life. Under this situation, BMD issues heavy
rainfall warning motioning its intensity with duration e.g moderately heavy 22-44mm,heavy 45-88 mm
and heavy 89 mm or more.
5. Aviation Warning:
For smooth and safety landing and take off of aviation warning is issued over an airport for hazardous, e.
g low cloud, thunder storm, heavy rainfall, poor surface visibility and squally wind.
BMD is going to be well equipped with modern technologies with the assistance of the Government ofJapan under the project “ Strengthening of weather warning services related to natural disaster in
Bangladesh”. It also provides radar in Rangpur and another one in Dhaka, which will help tp detect
thunderstorms, tornadoes and other meteorological and hydrological events.
The signal system is based on the wind speeds. Signal number will increase with the increasing wind of
the impending cyclone. Maritime and riverine signals are unified in the new system to avoid confusion.
The new proposed signal is given below:

Proposed Signals for River and Maritime Ports
SignalWind speed(Kph)

1.Cautionary Signals No 2
2.Warning Signal 4
3. Damage Signal No 6
4.Great Signal Number 8
5.Great Signal No. 9
6.Great Danger Signal No.10

20-40
41-61
62-87
88-117118-170
more than 171

With the inception of new equipment and modern technologies and new warning system in Bangladesh,the BMD in collaboration with CPP and other organizations related to disaster management will
hopefully handle the natural disasters more efficiently and easily in near future.

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3-3-3. REMEDIES FOR FLOODS IN SRI LANKA
1) INTRODUCTION
This article can be started with an event occurred in recent history in Sri Lanka. It was 5th June, 1992.
(World Environment Day). The South West monsoon broke over the Island throughout the night ending
the long period of drought. The rainfall was 494 mm (20 inches). Colombo city, the capital of Sri Lanka
was invaded stealthily and silently by the floodwater. No human being could come out for even an
emergency meeting because of the inclement weather. Many people woke up in the course of the night
to find 2 to 3 feet of water standing in their bedrooms. People were dazed and unable to understandwhat had happened. The city and its environment were paralyzed the following day. Many of the roads
were flooded and transport was not possible. The parliament building was visible in a sea of water like astranded ship. It was unapproachable and its ground floor was under water. A large number of shantydwellers occupying low-lying areas, often illegally, were completely destitute. The situation was samein some other districts like Matara, Kalutara, Rathnapura and Baticoloa. The people of these districts
realized that their cities are no longer the safe heaven they had thought to be. Whenever, wherever there
is a downpour in those districts the people of that area wonder whether their homes will get flooded orwhether they will get back home without having a wade knee deep through flooded streets to catch thebus home. These experiences force us to find a quick and systematic solution for this problem.
Generally flood is considered to be a phenomenon associated with an unusually high stage or flow overland or coastal area, which results in severe detrimental effects. It means if a place is submerged inwater it needs not to be called flood unless it causes damage and the process by which this damage iscaused. In the Webster’s new international dictionary, a ‘flood’ is defined as a “great flow of water,
especially, a body of water, rising, swelling, and over-flowing land not usually thus covered; a deluge; afreshet”
Floods are more of a common occurrence in Sri Lanka than the other natural disasters. There are morereasons for that. Firstly we can see most Sri Lankans, being an agricultural Community, had naturally
settled down in an environment suitable for that purpose. It means the location of a settlement has been
determined by the availability of water resources, woods, a stream, etc. Therefore river-valley lands
have always had a great attraction upon early settlers. On the other hand It was convenient to live close
to the river bank because rivers were the main arteries of traffic those days. Moreover the flood plains ofrivers are usually fertile and have relatively high moisture content, thus making them suitable for
agricultural development.
Whatever the historic reasons have been for the occupation of river-valley lands, it must be accepted asa fact that many villages, cities and towns are situated in areas that are subject to flooding in Sri Lanka.
The other reason that we can see is encroachments and unauthorized settlers in flood prone areas,
especially near big coastal towns like Colombo, Kalutara, Galle, Matara. It is a continuing problem
connected with flood problems.
Whatever the reasons for floods the present task should be to devise ways and means to protect thosecommunities from flooding; and not to bewail the fact that people have elected to live where they are.

2) TYPE OF FLOODS IN SRI LANKA(1) Flash floods: A flood that its peak flows in a short length of time after the storm or other event causing it. Often
characterized by high velocity flows. As I mentioned at the beginning Colombo and suburban cities are
more vulnerable for flash floods.
(2) Rain floods due to high intensity rainfalls: The very high rainfall and duration in the monsoon season often generate water volumes in excess of
the local drainage capacity, casing local floods. In Sri Lanka this is the main reason for flooding. The
country has experienced very intense rain very often. To make this clearer some exceptional rainfalls,
which occurred throughout the day in different parts of Sri Lanka, can be given as follows.

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Accumulation and Provision of Information on Natural Disasters and Disaster Reduction□■(3) Monsoon floods from major rivers: The major rivers generally rise slowly and the period of rise and fall may extend over 10-20 days, or
more. Spilling through distributaries and over the banks of the major rivers causes the most extensive
flood damage, particularly when several major rivers rise simultaneously. In Sri Lanka 103 river
basins were identified in 1959 an among them 10 rivers are considered as major. There are five rivers
among these major rivers, which are more vulnerable for floods. (Kalu, Keleni, Gin, Nilwala, andMahawali).
(4) Flood caused by human activities: This is one of the biggest reasons for floods in Sri Lanka. There is a rapid increase of converting forests,
grasslands and marshy lands to urban uses or agriculture purposes.
Although floods are a natural occurrence, most flood problems exit because of improper floodplain
development during some times long periods between floods. As there is no proper maintenance of law
and regulations by the relevant authorities improper land use pattern can be seen all over the country.
Some of the examples are given below.
(A) Erecting structures that deflect flows or increase downstream areas.
(B) Urbanizing watersheds and covering large areas with pavements and rooftops which increase
the amount and speed of runoff.
(C) Building drainage systems that accelerate flood flows to downstream erosion.
(D) Construction bridges, culverts, landfills, buildings and other encroachments that reduce thesize of the stream channel and natural storage areas, thus raising flood heights.

3) COST DUE TO FLOODS: Floods to the Sri Lanka economy as well as people have done more often heavy damages. In 1978
floods were followed by the cyclone and caused serious damages to the 28% of the country. In the very
recent history; November 2000, the flood in Baticoloa district caused heavy damage to the community.
4,000,000 people were rendered homeless. Over 3,000 acres of paddy fields were destroyed. Manyroads were impassable with the water rising 3.5 feet at certain point. Two people were reported lost.
In Sri Lanka there is not an accurate method to assess both tangible and intangible damages due tonatural disasters. But in general it is understood that the cost for replacing damaged properties, cost forevacuation, relief and rehabilitation of victims, cost due to disruption to commercial, industrial,
activities and damage to crops and livestock take a considerable portion of government expenditure.
4) FLOOD MITIGATION IN SRI LANKA
In Sri Lanka various kind of attempts, can be seen which the ancient people and rulers on flood control
have taken. One of the greatest king in the history once declared that not a single drop of rainwater
should flow to the sea without profiting the people. The ancient kings built number a of reservoirs. They
constructed large mounds, in order to have a place of escape. It proves that the attempts of man toprotect himself from flooding are as old as the history of civilization. But comparing to the ancient time
now the damages are much more. Although the nature of the flood is same its intensity is accounted tothe extent of the damage it causes. Today the population has gone up. People inhabit the areas, which isflood prone. Flood plain occupancy has increased. The increasing population occupies lowlands.
Therefore more developed and effective measures are needed to mitigate the sufferings of people fromfloods.
According to the proposed national disaster management plan and the measures, which have been taken
already, the present flood mitigation measures consist of two approaches. One is take water away fromthe people and the and the other one is to take people away from water, or We can identify them as flood
control and flood damage mitigation measures. These measures can be put into three strategies.
•••

Flood protection measures
Flood proofing
Flood preparedness41

■□ ADRC Annual Report 2000

(1) FLOOD PROTECTION MEASURES: This is the major and long-term structural measure that can be taken to prevent a designated area fromentering into floodwater. Safeguarding the day-to-day economic and social activities from the flood is
the main objective of this approach.
Many steps have been used and proposed according to this. Namely,(a) Storing flood water in reservoirs: In Sri Lanka most of ancient kings used to use this method. In this method a portion of flood flow will
be stored to minimize the flood peak at the point to be protected. Flood mitigation reservoir has it
maximum potential for flood reduction when it is empty. After a flood has occurred a portion of theflood mitigation storage is occupied by the collected floodwater and is not available for use until thiswater can be released. A second storm may occur before the draw down is completed. Consequently it isoften necessary to reserve a portion of the storage capacity as protection against a second flood.
The full capacity of the reservoir cannot be assumed to be available for the control of any single flood.
If a second flood occurred while the reservoir is full the effect of the reservoir might be make flood
worse.
The other thing is if we want to get more successful results from this an accurate flood forecasting
system is needed.
(b) Constructing dikes: This is accepted as the most economical, common and old flood protection method.
In Sri Lanka during 1930 to 1935 dikes were constructed on the both banks of Kalani river. Like wise
Gin river and Nilwala river were also tried to protect by constructing dikes. Although the Gin riverproject is quite successful, Nilwala project is not, owing to various reasons. The main problem that has
been identified in the dike system is that it provides protection only up to a certain level of flood. On theother hand a long period of absence of flood. This will create a feeling of security for inhabitants ofdike-protected areas leaving them unprepared for an eventual failure of the dike.
(c) Floodways and flood diversions: Floodways play two roles in flood mitigation. First, they create large, reservoirs, which store a large
portion of floodwater and hence decrease the flow in the main channel below the diversion. Second,
they provide an additional outlet for water from upstream, increasing velocity and decreasing stage forsome distance above the point of diversion.
Floodways is originally used only during major floods, and the land in the floodway may be used for
agriculture, although usually no fixed improvements of any value are permitted in the floodway area.
The other method that is suggested to cope up with flood in Sri Lanka is taking water away from theriver channel. The ancient people used this method by breaching a dike purposely in an area where theresultant damage is relatively small. In order to save dikes that protects another area where the damage
would be relatively large. Now it is realized that according to this method the better way is to have aspillway that sluices with gates and dissipaters energy.
Actually this method is quite effective and inexpensive means of flood. But to get more results somerequirements there. First one is the area where into which the floodwater are diverted should be freefrom habitation.
(d) Channel improvement: This method will improve the hydraulic capacity of the channel. Removal of brush and snags,
dredging of bars, straightening of bends, and other devices can be used to achieve this target. But theattention should be taken not to make the channel susceptible to bank erosion. The other thing that wehave to consider is some time the lining of channels may eliminate the natural recharge of the groundwater.
(e) Discharging drainage water by pumping:Pumping is usually used for the disposal of interior drainage water whenever adequate discharge by42

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gravity flow cannot be achieved because of limited outlets, insufficient storage capacity or because of
backwater caused by flooding.
(f) Vegetal covers: In some of the areas deforestation is the main reason for flooding. Vegetal cover is
identified as a better solution for these area. The vegetal cover can remove moisture from the soil and bytranspiration and that it also promotes loose organic soil, which is favorable for the infiltration of
rainfall. On the other hand a heavy vegetal cover means a high interception loss during storms. In Sri
Lanka these techniques are most commonly used in agricultural areas. They include maintaining trees,
shrubbery and vegetal cover, terracing, slope stabilization, using grass waterways, contour planning, andstrip framing.
(g) Flood plain management:The purpose of the flood plain management is to balance between the values obtainable from the use offloodplain and the potential losses to individuals and society arising from such use. This approach isdesigned to combat flood problems more effectively and to reconcile the objective of reduction ofdamage with benefit of preserving and enhancing natural floodplain values. Floodplain management isbased on:・ Controlling development of floodplains through regulatory measures and withholding financial
assistance from government for new developments and improvements to existing developmentareas subject to flooding.
・ Using wider range of tools to reduce flood losses to both existing and new structures andemphasizing use of those tools causing less severe environment impacts.
・ Assumption by state and provincial governments and private property owners of a greater share of
responsibility for the consequences of the floodplain development incorporating concern for
natural values into decisions about floodplain development and projects for flood loss reduction.
But Specific recommendation for flood-plain management should be developed very carefully. Because
the best solution will vary from stream to stream.

(2) FLOOD PROOFING: This method is consists of two strategies.
・ Flood proofing of specific properties
・ Flood adaptation
Flood proofing of specific properties:This measure are included with the provision of shutters to secure the building against the entry of flood
water, construction of building on elevated piers or earth mounds, construction of retaining walls aroundthe properties, or use of flood water resistant materials.
In areas where the floodwater is shallow and slow moving, sand bags can make temporary walls.
Furthermore elevating buildings above flood level is also another method for this.
(b) Flood adaptation
This is done through informing the people about the possibility of floods where they work or live.
According to this the height of flood level that can be reached, how to structure the home or shop or
farm, will be thought. Then the people themselves will take flood protection measures on their own
initiatives.
As an example in the rural areas farmers can take action to reduce susceptibility to flooding by
modifying their land management practices. They can remove the unwarranted obstructions done bythem selves.
Actually specific recommendation for flood mitigation should be developed from a deep study. The bestsolution will be differing from place to place. It depends on various kinds of facts. However to

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implement above strategies laws and regulations should be enacted.
According to the national disaster management plan those regulations are as follows:・Not permitting unrestricted new development in the hazard prone area.
・Anchoring and flood proofing structures to be built in known flood prone areas.
・Built-in safeguards for new water and sewage system and utility lines from flooding
・Enforcing risk zone, base flood elevation, and floodway requirements.
・Prohibiting of development in wetlands.
・Prescribing standard for different flood zones on flood maps.

(3) FLOOD PREPAREDNESS: Flood preparedness describes the wide rang of pre-emergency activities designed to reduce flood
impacts. This method is included the following strategies.
・ Forecasting and warning
・ Evacuation and sheltering
・ Relief work(a) Forecasting and warning: Objective of flood forecasting and warning system is to provide prediction for water level during floods
and inform appropriate authorities with a view of warning local officials and the community as soon as
possible. There are three essential stages in f & w.
・ Collecting rainfall data from upstream stations and catchments
・ Translate the data into expected water levels and their timing at key downstream locations.
・ Transmit the results to appropriate agencies, which may provide warning for floods to vulnerable
community.
(b) Emergency evacuation: Evacuation is regarded as a short-term measure and can be divided into three phases, such as pre-flood,
during flood and post flood. The greatest potential for reducing the number of casualties and flood
damage is during the pre-flood phase and as mentioned previously the degree of success is depend on
the effective flood forecasting and warning system.
If the flood becomes larger evacuation should be done during the flood. The post flood phase includes
relief and rehabilitation of the flood affected area.
(c) Flood relief
These arrangements provide the financial assistant to help the local authorities to meet the relief
requirement. In Sri Lanka, every year government efforts to regulate relief and rehabilitation, withrespect to various disasters have resulted in a number of policy guidelines and government circulars
including some gazette notification. It is therefore necessary to take stock of these existing instruments
and bring them under the purview of disaster management legislation and relief and rehabilitation policy.
The existing ad-hoc measures will have to be replaced to the extent possible with more definite
arrangements.
This would help in communicating the expectations of the administration.
Furthermore flood relief can be looked upon as zero premium insurance and does little to reduce theimpact of flood losses. Under a policy, which provides generous flood relief, there is a potential forflood relief payments to increase.
Past experience has shown that great deal of damage caused by flood is due to unprepared ness,inefficient warning system, lack of accurate information,
Inefficient administrative machinery, inadequate coordination between various departments, unplanned
actions and delay in mobilizing resources.
Therefore flood mitigation measures of Sri Lanka should be totally based on community needs and theyshould be planned from the perspective of the affected community and preparedness measures are based

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on following set of policies.
・ First priority in use of available resources shall be placed on protection of life.
・ The program shall be conservatively designed to ensure that personnel, organizations andequipments readily available within the community can effectively carry it out effectively.
・ Every practical precaution shall be taken to eliminate the need for unnecessary evacuation andprotective actions.
・ Arrangements shall be included for at least a minimum “stand along” capability to detect
impending floods and predict their magnitude and timing.
・ Individuals, business and others shall be given the opportunity to receive warning of potential
flooding in advance of those issued to the public, continent upon their recognition of potential
unreliability of such warnings.

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■□ ADRC Annual Report 2000

Proposed Institutional framework for flood mitigation in Sri Lanka: -National Council for Disaster Management

Relevant Ministries such as:- Social services,
Agriculture, Media, Health, science andtechnology, Housing and construction, Defense,
Mahaweli & Irrigation etc.

Technical
Advisory
Committee

National
DisasterManagement Center

Departments like:Dept of social services
Meteorological department
Irrigation department
Mahaweli authority
Central Engineering
Consultancy bureau
Health department
Police and armed forces
Agrarian research institute

Provincial Committees

District Committees

Divisional Committees

Village level Committees

Target group - victims

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Provincial level flood mitigation structure
Provincial Chief Secretary

National
Ministries

level

District secretary
Provincial Secretary for social
services

Provincial Director for social
Services

Divisional Secretary

Functions of each organization on flood mitigation (briefly)
Organization
Meteorological department

Irrigation department

Department of Media
Dept.of Social services
NDMC

District level committees

Police and arm forces
Department of HealthVillage level committees

Function
Observation, collection and analyzing the data.
Issuing weather forecasting.
Translate forecast in to warnings.
Flood prediction
Flood simulation studies and prediction of floods.
Observation, collection and analyzing hydrological data.
Recording and maintenance of flood levels in river basins.
Issue flood warnings.
Broadcasting all relevant information to the Public andorganization.
Relief and rehabilitation works.
Overall coordination.
Conducting Training and awareness programs.
Coordination with foreign disaster related organizations.
Preparing national action plan for flood mitigation.
Divide flood vulnerable areas into smaller areas for flood
preparedness.
Evacuation, relief and rehabilitation activities.
Preparing district action plan for flood mitigation.
Evacuation and other emergency activities.
Providing all the health care facilities.
preparing detail action plan for the village.
Maintaining an inventory of available resources and the historyof disasters in the village.
Assisting rescue and relief operation at the village level.

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