FLOODING – Frequently Asked Questions
What is flood and how it is classified?
Floods are defined as the overflow of areas that are not normally
submerged with water or a stream that has broken its normal
confines or has accumulated due to lack of drainage.
What are different types of flooding?

River flooding: River flooding occurs when heavy rains or
rapid snowmelt cause rivers to rise.

Coastal flooding: Coastal flooding may occur due to tidal
surges and flash flooding.

Flash Floods: Flash floods usually result from intense storms
dropping large amounts of rain within a brief period.

Dam Failure: Dam failures are potentially the worst flood
events. When a dam fails, a gigantic quantity of water is
suddenly let loose downstream, destroying anything in its path.
Can flood be forecasted?
Yes, with scientific development, flood forecasting is made much
in advance.
What are the Public Health risks related to flood?
The health problems relating to flood can be either due to direct
impact on human population, direct impact on existing
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infrastructure or the resultant effects due to combination of these
factors.
What are the hazards of flooding?
Urban Areas
Rural Areas
Massive amounts of erosion can be
accomplished by flood waters.
Such erosion can undermine bridge
structures, levees, and buildings
causing their collapse.
Flooding of farmland usually
results in crop loss. Livestock,
pets, and other animals are
often carried away and drown.
Water entering human built
structures
cause
water
damage. Even with minor flooding
of homes, furniture is ruined,
floors and walls are damaged, and
anything that comes in contact
with the water is likely to be
damaged or lost.
Flooding of
automobiles usually results in
damage that cannot easily be
repaired.
Transportation systems may be
disrupted,
resulting
in
shortages of food and clean-up
supplies. Food grains stored at
home or in go-downs get wet
and start rotting. In under
developed countries food
shortages often lead to
starvation
Gas and electrical service may be
disrupted. Water supply pipes/
system get damaged and wells get
inundated creating shortage of
drinking water.
The affected communities
living in temporary shelters/
resettlements have limited or
no access to safe drinking
water, food etc. In addition,
prevailing unhygienic sanitary
conditions make it conducive
for spread of food and waterborne diseases.
Hazards Common to both rural and urban areas:
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
Humans that get caught in the high velocity flood waters are
often drowned by the water.

Floodwaters can concentrate garbage, debris, and toxic
pollutants that can cause the secondary effects of health
hazards.

Drinking water supplies may become polluted, especially if
sewerage treatment plants are flooded. This may result in
disease and other health effects.

Cooking fuel gets spoiled/wet making it difficult to cook food
and also drinking water contamination poses many water/food
borne diseases.

Washing away of property, pet animals and crops result in to
severe economic losses and mental stress.

Hypothermia may also be a problem, particularly in children, if
trapped in floodwaters for lengthy periods. There may also be
an increased risk of respiratory tract infections due to exposure
(loss of shelter, exposure to flood waters and rain).

Effects on mental health include Post Traumatic Stress
Disorder; excessive grief, sleep disorders; exaggeration of
existing illness; death wish & suicidal ideation.

Reproductive Health - Pregnant mothers and newborns become
vulnerable and require additional care.
What are the diseases related with flooding?
Floods can potentially increase the transmission of the following
communicable diseases:
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
Water-borne diseases, such as typhoid fever, cholera,
leptospirosis and hepatitis A

Vector-borne diseases, such as malaria, dengue and dengue
haemorrhagic fever, yellow fever, and West Nile Fever

Food-borne diseases.
Types of ailments
1) Respiratory diseases
2) Injuries (not very
common)
3) Water-borne diseases
(diarrhoeal
diseases/cholera,
gastroenteritis,
dysentery etc.),
Infective Hepatitis,
Poliomyelitis.
4) Malaria / Filaria
5) Skin diseases / Eye
Diseases
6) Snake / Insects bite
Due to
Adverse condition of living
Collapse of houses/standing structure
Non-availability or inadequate
availability of drinking water due to:
 Flooding of wells, which cause
pollution to the water
 Breakdown of piped water supply
 Inaccessibility of available water
sources because of damages caused
by flood.
 Unsanitary conditions in villages /
evacuation camps due to:
accumulation water, lack of excreta
disposal; blockage / disruption of
normal drain; slush with increase in
breeding space for flies;
overcrowding at temporary shelters.
 Dumping of compound dry-waste
 Dumping of animal excreta
 Dumping of carcasses
Increase in mosquito breeding space
Lack of personal hygiene and
overcrowding
Water entering into their shelters
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What preventive measures should be undertaken following
flood?
Water-borne diseases are one of the most common phenomena
during flood. Diarrhoeal diseases are one of earlier manifestations
but diseases like typhoid, infective hepatitis and poliomyelitis are
usually seen after about a fortnight. Therefore consumption of
safe drinking water, maintenance of good personal hygiene and
sanitary arrangement is the key measures.
Which are the water-borne diseases associated with flooding?
The major risk factor for outbreaks associated with flooding is the
contamination of drinking-water facilities. There is an increased
risk of infection of water-borne diseases contracted through direct
contact with polluted waters, such as wound infections,
dermatitis, conjunctivitis, and ear, nose and throat infections. The
only epidemic-prone infection which can be transmitted directly
from contaminated water is leptospirosis. Transmission occurs
through contact of the skin and mucous membranes with water,
damp soil or vegetation (such as sugarcane) or mud contaminated
with rodent urine.
Which are the vector-borne diseases associated with flooding?
Floods may indirectly lead to an increase in vector-borne diseases
through the expansion in the number and range of vector habitats.
Standing water caused by heavy rainfall or overflow of rivers can
act as breeding sites for mosquitoes, and therefore enhance the
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potential for exposure of the disaster-affected population and
emergency workers to infections such as dengue, malaria etc.
Which are the food-borne diseases associated with flooding?
Food in affected areas may become contaminated and
consequently be at risk for outbreaks of food-borne disease,
including diarrhoea, dysentery, cholera, hepatitis A, and typhoid
fever. Poor sanitation, including lack of safe water and toilet
facilities and lack of suitable conditions to prepare food have led
to mass outbreaks of food-borne disease.
What measures can be taken towards water safety?

For point-of-use or household water treatment, the most
practical forms of free chlorine are liquid sodium hypochlorite,
solid calcium hypochlorite and bleaching powder (chloride of
lime; a mixture of calcium hydroxide, calcium chloride and
calcium hypochlorite).

The amount of chlorine needed depends mainly on the
concentration of organic matter (impurities that consume some
chlorine) in the water and has to be determined for each
situation. After 30 minutes, the residual concentration of active
chlorine in the water should be between 0.2-0.5 mg/l, which
can be determined using a special test kit.

In case of damages to centralized (community) system of water
treatment, household water treatment methods like boiling,
filtration (with cloth or sand or ceramic candle), settlement,
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chlorination or permanganate, solar disinfection etc can be
adopted.

Drinking water should be stored of in clean, covered and
narrow mouthed containers.

Use only tap or ladle to draw water if stored in a wide-mouthed
container.
What measures can be taken to ensure food safety?

Avoid raw and uncooked food unless it can be peeled or
shelled.

Cook food thoroughly and eat it while still hot.

Cooked food should not be stored for a long time. Keep the
food covered and reheat it thoroughly before consuming

Keep the cooking utensils and kitchen area clean and wash
hands before handling food.
How can vector-borne diseases be prevented?

Insecticide treated mosquito nets (ITN) are suitable if nets were
previously used by the population, and if living in structures
that allow mosquito nets to be supported or hung.

Indoor spraying of residual insecticide ("house spraying") has
been the method of control most often used.

Insecticides: implementation of preventive measures such as
indoor residual spraying, or the retreatment/distribution of
Insecticide Treated Nets (ITNs) in areas where their use is
well-known.
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DOs & DON'Ts
After the flood, “DO”:

Do enhance drying out of buildings by carefully removing mud,
standing water, and water-logged furnishings and debris.

Do remove residual moisture gradually by allowing structures
to dry naturally. Open doors and windows.

Do document the damage for insurance purposes by taking
notes or photographs.

Do BEFORE removing items from water, prepare a clean, dry,
well-ventilated temporary area for sorting and storing your
objects. Wet objects should be moved only once because they
are fragile, so setting aside such an area is vital.

Do wear rubber gloves, and, if possible, a face mask, when
handling items.

Do provide support for damaged objects when moving them,
such as a cart, or a flat, sturdy surface.

Do call an expert if in doubt about how to salvage any
materials.
After the flood, “DON'T”

Don't remove standing water in a basement too fast. If the
pressure is relieved too quickly it may put undue stress on the
walls.

Don't dry buildings with mechanical dehumidifiers, which may
draw out moisture too quickly and cause additional damage.
Allow structures to dry naturally.
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
Don't scrub or brush mud and other deposits from materials.
This may cause further damage.

Don't let water-damaged papers remain in wet boxes--remove
water-damaged papers from wet boxes then air dry or freeze
dry.

Don't open any books or albums that were completely
submerged. (Wet paper is very weak and will tear.)

Don't keep objects in dark, hot, stagnant air with high humidity-these conditions encourage mold.

Don't try to separate bundles of saturated paper.
Water Borne Diseases
DO’s

Drink water from a safe source or water that has been
disinfected (boiled or chlorinated).

Store water in narrow mouthed container with lid/cover and
use ladle or tap to draw water

Cook food or reheat it thoroughly and eat it while it is still hot.

Keep food items covered.

Wash hands before preparing or eating food and after
defecation.

Increase fluid intake in case of diarrhoea. Use ORS solution or
home available fluids as soon as diarrhoea starts.

Refer the diarrhoea case to a health facility in case of following:
 Child is irritable, restless or lethargic or unconscious.
 Eating or drinking poorly.
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 Child has marked thirst.
 Child has fever or blood in stool.
DON'Ts

Don't drink water from unsafe sources.

Don't eat uncooked food unless it is peeled or shelled.

Don't eat cut fruits.

Don't defecate indiscriminately.
Vector Borne Diseases
DO's

Use insecticide treated bed nets (ITBN) or insect repellents
while sleeping to keep away mosquitoes.

Wear cloths that cover arms and legs.

Keep patients protected from mosquito bite in acute phase.

Empty water containers at least once a week. Cover and seal
septic tanks and soak-away pits.

Remove water from coolers and other places where water has
remained stagnant.

All fever cases to be given presumptive treatment for malaria.
DON'Ts

Don't allow water to stagnate.

Do not allow discarded items to accumulate such as tyres,
tubes, empty coconut shells, household items and objects where
water may collect.
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
Discourage children from wearing shorts and half sleeved
cloths.
Food-borne diseases
KEEP FOOD AT SAFE TEMPERATURES (prevent growth of
microorganisms)

Eat cooked food immediately and do not leave cooked food at
room temperature longer than 2 hours

Keep cooked food steaming hot (more than 60°C) prior to
serving

Cooked and perishable food that cannot be kept refrigerated
(below 5°C) should be discarded
COOK THOROUGHLY (kill dangerous microorganisms)

Cook food thoroughly, especially meat, poultry, eggs and
seafood until it is steaming hot throughout

For cooked meat and poultry to be safe their juices must run
clear and no parts of the meat should be red or pink

Bring foods like soups and stews to boiling and continue to
boil for at least 15 minutes to make sure all parts of the food
has reached at least 70°C.

While cooked food should generally be eaten immediately, if
necessary thoroughly reheat cooked food until it is steaming
hot throughout.
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ANNEXURE – 1
FLOOD PREPAREDNESS
What you should know?

80% of flood deaths occur in vehicles, and most happen when
drivers make a single, fatal mistake trying to navigate through
floodwaters.

Just 6 inches of rapidly moving floodwater can knock a person
down.

A mere 2 feet of water can float a large vehicle even a bus.

One-third of flooded roads and bridges are so damaged by
water that any vehicle trying to cross stands only a 50% chance
of making it to the other side.

Know your neighborhood flood history

If it has been raining hard for several hours, or steadily raining
for several days, be alert to the possibility of a flood.

Floods can take several hours to days to develop.

A flood WATCH means a flood is possible in your area.

A flood WARNING means flooding is already occurring or will
occur soon in your area

Flash floods can take only a few minutes to a few hours to
develop.

A flash flood WATCH means flash flooding is possible in your
area.

A flash flood WARNING means a flash flood is occurring or
will occur very soon.

When a flood WARNING is issued, Listen to local radio and
TV stations for information and advice. If told to evacuate, do
so as soon as possible.

When a flash flood WATCH is issued— be alert to signs of
flash flooding and be ready to evacuate on a moment’s notice.
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
When a flash flood WARNING is issued— or if you think it
has already started, evacuate immediately. You may have only
seconds to escape. Act quickly!

Stay alert for changing weather conditions

Listen to local radio or TV for flood information.

Get out of areas subject to flooding like low spots, canyons, and
areas downstream from dams

Consider purchasing flood insurance

Do not attempt to cross water that is above your knees

Do not drive over a flooded road

Abandon a stalled vehicle and immediately move to higher
ground

Move to higher ground away from rivers, streams, creeks, and
storm drains. Do not drive around barricades - they are there for
your safety.

If your car stalls in rapidly rising waters, abandon it
immediately and climb to higher ground.
Remember, it does not have to be raining for a flash flood to
occur. Some of the most dangerous floods originate many miles
away.
What to do before the flood?
When you receive a Flood Watch:
 A Watch is issued when flooding is possible within the watch
area. When a flood watch is issued, you should be aware of
potential flood hazards. Everyone in a Watch area should be
ready to respond and act quickly.
 Have an evacuation plan in place BEFORE flooding occurs.
Flooded roads may cut off your escape route. Head for higher
ground before the water becomes too deep. Remember – just
six inches of rapidly flowing water can knock you off your
feet.
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 Know your flood risk and the elevation above which flooding
occurs. Do streams or rivers near you flood easily? If so, be
prepared to move to a safe place. Know your evacuation routes.
 Develop an evacuation plan. Everyone in your family should
know where to go if they have to leave.
 Discuss flood plans with your family. Everyone should know
what to do in case all family members are not together.
Discussing flood plans ahead of time helps reduce fear and
anxiety and lets everyone know how to respond.
 Determine if the roads you normally travel to reach your home
or job will be flooded during a storm. If so, look for alternative
routes to use during flooding.
 Keep a battery-powered portable radio, emergency cooking
equipment, and flashlights in working order with extra
batteries.
 Have a professional install check-valve in plumbing to prevent
flood waters from backing up into the drains of your home.
 Keep your automobile fueled; if electric power is cut off, gas
stations may not be able to operate pumps for days.
 Store drinking water in food-grade containers. Water service
may be interrupted.
 Keep a stock of food requiring little cooking and no
refrigeration; electric power may be interrupted.
 Keep first-aid supplies and prescription medicines on hand.
What to do during the flood?
 If advised to evacuate, do so immediately! Families should use
only one vehicle to avoid getting separated and reduce traffic
jams. Move to a safe area before access is cut off by flood
water. Continue listening to radio or television for information
concerning the flooding.
 Don’t drive if you don't have to.
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 Get out of areas subject to flooding. This includes dips, low
spots, canyons, washes, etc.
 Do not attempt to cross flowing streams.
 Never try to walk, swim, drive, or play in flood water. You
may not be able to see how fast the flood water is moving or
see holes or submerged debris.
 Do not camp or park your vehicle along streams and washes,
particularly during threatening conditions.
 Be especially cautious at night when it is harder to recognize
flood dangers.
 Do not attempt to drive through a flooded road. The depth of
water is not always obvious. The road bed may be washed out
under the water, and you could be stranded or trapped.
 Do not drive around a barricade. Barricades are there for your
protection. Turn around and go another way!
 If the vehicle stalls, leave it immediately and move to higher
ground. Rapidly rising water may engulf the vehicle and its
occupants, sweeping them away. Vehicles can be swept away
by as little as two feet of water.
 Children should NEVER play around high water, storm drains,
viaducts, or arroyos. It is very easy to be swept away by fastmoving water.
 If you come upon a flowing stream where water is above your
ankles, STOP! Turn around and go another way. Climb to
higher ground. If it is moving swiftly, even water six inches
deep can knock you off your feet. Many people are swept away
wading through flood waters, resulting in injury or death.
What to do in case of a flash flood?
There may be no time for a warning to be issued. You may have
only seconds to escape. It could be a life-and-death decision for
you and your family. If you suspect a flash flood is about to
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happen immediately climb to higher ground. Avoid walking
through any swiftly-moving floodwaters. Even water that is 6
inches deep can sweep you off your feet. If you are in a car and
come to a flooded area, turn around and go another way. If your
car stalls, abandon it immediately and climb to higher ground.
Many deaths have resulted from attempts to move stalled
vehicles.
What to do for evacuation?
Expect the need to evacuate and prepare for it. When a flood
watch is issued, you should:
 Fill your vehicle’s gas tank and make sure the emergency kit
for your car is ready.
 If no vehicle is available, make arrangements with friends or
family for transportation.
 Fill your clean water containers.
 Review your emergency plans and supplies, checking to see
if any items are missing.
 Tune in the radio or television for weather updates.
 Listen for disaster sirens and warning signals.
 Put livestock and family pets in a safe area. Due to food and
sanitation requirements, emergency shelters cannot accept
animals.

Adjust the thermostat on refrigerators and freezers to the
coolest possible temperature.
What to do if you are ordered to evacuate?
You should never ignore an evacuation order. Authorities will
direct you to leave if you are in a low-lying area, or within the
greatest potential path of the rising waters. If a flood warning is
issued for your area or you are directed by authorities to evacuate
the area:

Take only essential items with you.
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
If you have time, turn off the gas, electricity, and water.

Disconnect appliances to prevent electrical shock when power
is restored.

Follow the designated evacuation routes and expect heavy
traffic.

Do not attempt to drive or walk across creeks or flooded roads.
What to do if you are ordered not to evacuate?

Monitor the radio or television for weather updates.

Prepare to evacuate to a shelter or to a neighbor's home if your
home is damaged, or if you are instructed to do so by
emergency personnel.
What You Can Do After the Flood?

Get necessary medical care at the nearest hospital.

Do not visit disaster areas. Your presence might hamper rescue
and other emergency operations.

If the power is out, use flashlights, not candles.

Use flashlights, not lanterns, torches, or matches, to examine
buildings. Flammables may be inside.

Report broken utility lines to appropriate authorities.

Boil drinking water before using. Wells should be pumped out
and the water tested for purity before drinking. If in doubt, call
your local public health authority.

If fresh or canned food has come in contact with flood waters,
throw it out.

Take steps to reduce your risk of future floods. Make sure to
follow local building codes and ordinances when rebuilding,
and use flood-resistant materials and techniques to protect
yourself and your property from future flood damage.
Your emergency supplies kit to Include:
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
At least a 3-day water supply (Five liters per person per day)

Food that won't spoil

One change of clothing and footwear per person

One blanket or sleeping bag per person

First aid kit and manual

Essential medicines

Contact lenses, extra eyeglasses and dentures

Baby supplies such as formula, bottles, diapers, powdered milk
and medications

Feminine supplies and personal hygiene items

Special items for infant, elderly, and disabled family members

Mess kit or paper cups and plates and plastic utensils

Battery operated radio and extra batteries

Flashlight with extra batteries

Cash or traveler's checks, change

Extra set of car keys

Soap, liquid detergent

Cash and credit card

Entertainment--book and games

Utility knife and can opener

Map of area
Remember to keep important family documents in a
waterproof, portable container you can grab quickly in case of
evacuation.

Insurance policies, wills, contracts, deeds, stocks and bonds

Passports, social security cards, immunization records

Bank account numbers

Credit card account numbers and companies
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
Inventory of valuable household goods, important telephone
numbers

Family records (birth, marriage, death certificates)
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ANNEXURE – 2
Effects of flooding on health
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