FLOODS AND FLASH FLOODS

By

Bhaskar Karnick, V.Krishna Moorthy

Contents

01. Introduction 02. What is flood? 03. What causes Flood?  04. Recent floods in India 05. Great floods in India  06. Flood and health factors 07. Destruction caused by flood 08. Flood and economy 09. Flood Forecasting and networking in India  10. Conclusion 11. Reference Links

"The only thing that stops God from sending another flood is that the first one was useless". - Nicholas Chamfort (1741 - 1794)

Introduction

After prayers to the rain gods, answered in excess in parts of our country, now, the focus has shifted to floods.  Many states in our country are flood prone due to heavy rain or otherwise. The flood causes loss to human life and wide spread damage to property. Unimaginable damage to agriculture takes place affecting the States planning and upset the financial budgeting there by slowing down the whole economy of the country.

People not affected by the flood tend to ignore the event thinking that it does not affect them so why bother?. 

Flood is not unique to our country. Floods come in different parts of the world. Floods are the biggest cause of loss of life every year through out globe. Majority of countries do not document or map floods methodically. People are generally taken by surprise by the floods as they may come in the night when every body is asleep, giving very little time for evacuation. Water remains stag anent after the flood recedes, source of drinking water get polluted and the food get spoiled. People are left with no resource to combat the natural calamity that has take place. Floods are ugly part of our system we cannot ignore or wish them away. The only way to fight the floods is to try to predict the flood, prepare for it, train and educate people. identify areas, which are flood prone. 

What is flood

The term "flood" is a general or temporary condition of partial or complete inundation of normally dry land areas from overflow of inland or tidal waters or from the unusual and rapid accumulation or runoff of surface waters from any source.

Flooding and flash flooding are the deadliest of natural disasters. Floodwaters claim thousands of lives every year and render millions homeless. One of the more frightening things about flooding is that it can occur nearly anywhere, at any time. It can result from excess water jams on rivers, even moderate rain, or a single very heavy downpour as it occurred in Himachal Pradesh recently.

"In the last 30 years, inland flooding has been responsible for more than half the deaths associated with tropical cyclones in the United States." 
Ed Rappaport
National Hurricane Center 

What causes Flood ?

Heavy down pore in the form of rain, brings down more water than can be disposed off by combined factors natural and man made systems causes flooding. The rivers overflow embankments may be breached. Generally rains following storm and hurricane are heavy and bring unmanageable amount of water causing flash floods. 

The frequency or probability of a flood usually is described by assigning a recurrence interval to the flood at each gaging station. This is accomplished by statistically evaluating long-term annual peak stream flows at a station. Standard techniques and procedures used to determine the station flood-frequency relations are described by the U.S. Water Resources Council (1982). For example, a 100-year flood-recurrence interval means that, in any given year, a flood of a specified stream flow magnitude has a 1-in-100 chance of happening.

Rainfall is generally heaviest with slower moving storms (less than 10 mph).

To estimate the total rainfall in inches from a hurricane, divide 100 by the forward speed of the storm in miles per hour (100 / forward speed = estimated inches of rain).

When it comes to hurricanes, wind speeds do not tell the whole story. Hurricanes produce storm surges, tornadoes, and often the most deadly of all - inland flooding. 

While storm surge is always a potential threat, more people have died from inland flooding in the last 30 years. Intense rainfall is not directly related to the wind speed of tropical cyclones. In fact, some of the greatest rainfall amounts occur from weaker storms that drift slowly or stall over an area. 
Inland flooding can be a major threat to communities hundreds of miles from the coast as intense rain falls from these huge tropical air masses. 

The ingredients for a hurricane include a pre-existing weather disturbance, warm tropical oceans, moisture, and relatively light winds aloft. If the right conditions persist long enough, they can combine to produce the violent winds, incredible waves, torrential rains, and floods we associate with this phenomenon.
Each year, an average of ten tropical storms develop over the Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. Many of these remain over the ocean and never impact the U.S. coastline. Six of these storms become hurricanes each year. In an average 3-year period, roughly five hurricanes strike the US coastline, killing approximately 50 to 100 people anywhere from Texas to Maine. Of these, two are typically "major" or "intense" hurricanes (a category 3 or higher storm on the Saffir -Simpson Hurricane Scale. 
A hurricane is a type of tropical cyclone, which is a generic term for a low pressure system that generally forms in the tropics. The cyclone is accompanied by thunderstorms and, in the Northern Hemisphere, a counterclockwise circulation of winds near the earth's surface. Tropical cyclones are classified as follows:

Sustained winds
A 1-minute average wind measured at about 33 ft (10 meters) above the surface.

1 knot = 1 nautical mile per hour or 1.15 statute miles per hour. Abbreviated as "kt".

Tropical Depression
An organized system of clouds and thunderstorms with a defined surface circulation and maximum sustained winds* of 38 mph (33 kt**) or less

Tropical Storm
An organized system of strong thunderstorms with a defined surface circulation and maximum sustained winds of 39-73 mph (34-63 kt)

Hurricane

An intense tropical weather system of strong thunderstorms with a well-defined surface circulation and maximum sustained winds of 74 mph (64 kt) or higher
 
Hurricanes are categorized according to the strength of their winds using the Saffir - Simpson Hurricane Scale. A Category 1 storm has the lowest wind speeds, while a Category 5 hurricane has the strongest. These are relative terms, because lower category storms can sometimes inflict greater damage than higher category storms, depending on where they strike and the particular hazards they bring. In fact, tropical storms can also produce significant damage and loss of life, mainly due to flooding.

Some time the factors like flow of water getting blocked as in Northern Russia. An unusually cold winter caused large amounts of ice to form along the river, which drains into the Barents Sea. When the river began to thaw, huge chunks of ice floated downstream, gathered at the mouth of the river, and formed a dam. The waters backed up for hundreds of kilometers and threatened to pour in on the 35,000 residents in the city of Naryen-Mar. In a last-minute attempt to save the town, the Russian air force brought in four SU-24 assault aircraft and dropped ninety-six 250-kg bombs on the ice, with little effect. Eventually the town had to be evacuated (Associated Press, June 4, 1998). 

While most floods follow heavy rain, or rapid, widespread melting of deep snow, flood forecasters also have to worry about several other factors. Here are the factors that help determine whether a flood is minor or major: 

Deep snow cover. Deep snow can melt into a lot of water. Deep snow very rarely causes flooding by itself. Often, heavy rain and rapid warm ups combine with rapidly melting snow to cause major flooding problems. For example, Fargo, S.D. had a 15 inch snow pack at the beginning of March 1994. Fortunately, slowly warming temperatures along with below freezing overnight temperatures through most of March into April reduced flooding from melting snow. Forecasters were originally concerned that the deep snow would pose significant problems during the spring thaw. 

Frozen ground. Frozen soil can not absorb as much water as unfrozen soil. Rain or rapid snow melt atop frozen soil can cause flooding that wouldn't have occurred if the soil were not frozen. 

Wet or saturated soil. Saturated soil can't absorb rain and water from melting snow. The excess water becomes runoff that rapidly flows into rivers and streams. Unsaturated soil acts like a sponge, absorbing some of the water from rain or snow melt. Saturated soil by itself does not cause flooding. Usually, heavy rain or rapid snow melt combined with saturated soil causes the flooding. 

 Full reservoirs. Reservoirs are large, mostly man-made basins that hold water for irrigation and drinking. Reservoirs can alleviate river flooding by absorbing and spreading out flood crests flowing down the river. This would reduce the height in which the water rises downstream of the reservoir. If the reservoir is already full, then it can not absorb any water from swollen rivers. 

High river and stream levels. Streams or rivers that are already at bankfull can be a precursor to major flooding. Heavy rain or rapid snow melt that flows into an already full river will cause the river to overflow its banks and flood nearby locations. High river levels, such as those in the Ohio Valley in the spring of 1997, make forecasters very nervous anytime a storm threatens to dump heavy rain over the region. A prolonged dry spell, however, can alleviate flooding concerns. 

Ice-covered rivers. As rain or melting snow fill river, ice at the surface cracks and breaks up into chunks that float downstream. These chunks of ice can form a dam as they run into barriers, such as bridges, along the rivers. The ice dams cause water to rise rapidly behind them, flooding many upstream locations. If the dam suddenly breaks, water can also flood downstream locations. Large chunks of ice can also damage bridges and other structures. A USA TODAY graphic has more on ice jams. 

Widespread, heavy rain. This is perhaps the most important and influential factor of them all. Long periods of heavy rain can cause flooding even if all other factors are unfavorable for flooding. Often, heavy rain is a cause of some of the factors listed above such as wet soils, high stream levels and full reservoirs. The Midwest flooding during the summer of 1993 and the Southeast flooding caused by the remnants of Tropical Storm Alberto in 1994 are a couple of examples of flooding caused by heavy rain.

Whether or not these factors cause flooding often depends on daily weather conditions over the region such as temperature and precipitation. This makes long range flood forecasts very difficult to pin down, which is the main reason why hydrologists often forecast long range flood potential rather than actual long range flood forecasts.

Recent Floods in India 

ARUNACHAL PRADESH (As on 9-07- 2003): 

8 districts viz. W/ Kamang, P/ para, E/ Siang, W/ Siang, U/ Siang, Lohit, Changlanf and Tirap have been affected in varying degrees due to floods/heavy rains and landslides since 15.6.2003. Detailed reports from districts are awaited. State Government has instructed districts authorities to take necessary rescue & relief measures in the affected areas. Flood affected people evacuated to safe places. Roads communication disrupted. Petrol pump, play ground, water tanks & pipelines were also reported damaged due to floods and landslides. 

ASSAM(As on 10-07- 2003): 

According to the report of the State Government 20 districts were affected by heavy rains and floods, these are Kamrup, Nalbari, Dhemaji, Karimganj, Hailkandi, Darrang, Dhubri, Golpara, Moigaon, Golaghat, Sonitpur, Jorhat, Sivasagar, Nagaon, Barpata, Karbi-Anglong, North lakhimpur,Dibrugarh, Bongaigaon and Tinsukia. In Kamrup district road communication in a few places and in Demaji districts road communication at NH -- 52 in between Bhojo and Kekuri Ahomgaon still disrupted. Roads communications at many places in the affected districts still remains disrupted. Districts authorities have been shifted affected families to School/ Institutions buildings and safer places. Soil erosions are still continuing in several parts of the affected districts. Over all floods situation in the many districts of the State are remains unchanged. The worst affected districts of Dhemaji, Goalpara, Dhubri, Nalberi, Nagaon and Hailakandi have no let up in the flood situation since the last few days. 
The State Government has distributed gratuitous relief viz; Rice 3528 quintals, Dal 235 quintals, salt 89 quintals and number of water purifying packets among the affected people. 23 relief camps have been opened. Districts authorities have deployed numbers of boats for rescue and relief operations. 

BIHAR(As on 10-07- 2003): 

Five districts viz. Madhubani, Muzaffarpur, Sitamarhi, Saharsa and Sheohar have been affected in varying degrees due to flood/ heavy rains. State Government has issued instructions to Collectors of all flood prone districts for taking necessary measures to provide the safety and security of the affected people. Funds have been allotted to rescue & relief the flood-affected people. 133 country boats have been deployed for rescue and relief operations. Meetings with Army officers and GM East-Central Railways have been held and emergency plans have been formulated to meet the situation. 

KERALA(As on 10-07- 2003): 

As per information received from the State Government, 14 districts have been affected due to heavy rains/ floods. 402 families affected. 2 persons missing and 36 persons reported injured. 182 houses fully and 1258 houses partially damaged. The State Government has evacuated 222 families and opened 13 relief camps, for affected people. 

MAHARASHTRA(As on 30-06- 2003): 

As per information received from the State Government 16 districts have been affected due to heavy rains/ floods. The State Government is providing relief to the affected population. 

WEST BENGAL(As on 10-07- 2003): 

As per the State Government during the early hours of the morning today (7th- 8th night) a major landslide was occurred at Sewak Road, which connects Sikkim to Darjeeling. According to the preliminary report, 17 persons have lost lives, 8 persons missing and 3 persons reported injured. Communication on NH 55 and NH 31 A has been disrupted. NH 55 near Sukna on Panchnadi have been repaired and traffic system is restored for plying from Siliguri to Gangtok, Darjeeling & Kalimpong. Road to Darjeeling via Pankhabari is likely to be reparired by 11-7-03. Work on NH 55 (Hill Cart Road) and Siliguri Mirik State Higway is going on. The district authority (in association with Border Road Organization) is making efforts for early restoration of traffic. At some places river/ road and irrigation embankments are reported damage. 
Relief teams with essential commodities etc. have been sent to site. 8 Gruel Kitchens are in operation for 1052 affected persons at Gayabari. 3 Relief Shelters with 75 families are in operation in Siliguri. 
In Cooch Behar 2 camps have been opened for 171 families. Boats and rescue teams have been kept in readiness in all the vulnerable areas. 
In Uttar Dinajpur, river Dauk at Chopra is flowing above warning level and Mahanada close to the wrniing level. In Dakshin Dinajpur, Tangan is close to warning level. In Malda, the rivers are also raising and red alert flashed for unprotected areas of Fulhar in Harishchanrapur, Ratua and Khorba though the level are reported below danger level. 
Include table Damage due to Cyclone, Heavy Rains & Flood during - South- West Monsoon, 2003

Great floods in India

Assam; worst floods in 50yrs Wednesday, July 16 2003 17:00 Hrs (IST)

Guwahati: A state of emergency was declared in the flood-hit Assam on July 16, with authorities describing the flooding as the worst in 50 years. 

This is the biggest flood in 50 years, Assam Chief Minister Tarun Gogoi said in a letter of appeal for funds to the Central government. There may be further devastation in the coming days because flood- management structures throughout the state have been damaged by the two successive waves of floods this year, the letter warned. 

At least 3.7 million people have been displaced in more than two weeks of devastating floods in Assam, which have swamped more than 20 of the state's 24 districts. 

The Brahmaputra burst its banks at several places overnight, flooding fresh areas in the state, according to Assam Flood Control Minister Nurzamal Sarkar. There seems to be no respite with the river breaching mud embankments everywhere. 



News from GENEVA

Worst floods in India leave millions homeless

From franki@elca.org
Date 29 Sep 2000 09:46:03


GENEVA, 29 September 2000 (LWI) - As the death toll mounts in the worst flooding in India and Bangladesh in recent years, the field program offices of the Lutheran World Federation (LWF) say food, medicine and shelter are desperately needed. 

Lutheran World Service (LWS)-India reports the severe overflow of riverbanks and dams following heavy monsoon rains on September 18, have divided the eastern state of West Bengal into two, with the northern and southern parts cut off from each other. In India alone at least 400 people have reportedly died as result of the disaster and another 15 million have been rendered homeless.

With the available resources, LWS-India has begun intervention in selected communities, where extensive damage was incurred. It is expected that at least 10,000 families can receive immediate assistance. The LWF program aims at providing food, clothes, blankets, building materials and seeds and fertilizers. The first response from LWS India to the floods is medical care to the victims in order to minimize the spread of water-borne diseases. 

According to LWS-India, the waters have swept away roads and railway tracks. Whole villages and huge areas of farmland have been washed away and thousands of livestock are believed to have died.

The LWS-India emergency relief team started moving into the affected areas when it became possible. Mushidabad district in the northern part of the state is the worst hit with some 5.6 million people affected by waters reaching a level of four meters. Reports from the accessible areas of the district indicate that about 46,000 houses were totally destroyed and many parts still remain inaccessible. 

Army helicopters are dropping food parcels to millions of marooned villagers. Elsewhere soldiers use boats to rescue stranded victims and relief camps have been set up. Officials were quoted by newspapers as saying cases of intestinal disease have already been reported from some of the camps. 

Earlier in August when five million people were affected by floods in the states of Assam, Bihar and West Bengal, the Geneva-based Action by Churches Together (ACT), a worldwide network of churches and agencies responding to human need through coordinated emergency response, issued an Appeal for assistance to flood victims in India. LWS, an ACT member, reports that in Assam and Bihar people are going back in small numbers to their villages. "They are returning to collapsed houses, silted fields and damaged crops. Whether in relief camps on the embankments or back home, they face the same set of problems. No shelter, no safe water and of course crisis of food," the report says.

LWS-India reported in August that unprecedented silting had occurred during the recent floods in the state of Assam. "Several thousand hectares of croplands have been rendered useless by thick deposits of silt and slush. In some areas several feet of silt have been deposited over the land. The report added that the huge amount of silt in the riverbeds diverted the course of swollen rivers, which inundated entire villages.

1978: Floods devastate northern IndiaAt least two million people have been made homeless as the worst floods in living memory hit northern India. Some areas of the state of West Bengal are now 18 feet (5.49 metres) below water as the monsoons continue beyond their usual season. The river Yamuna has risen six feet (1.83 m) above its official "safe level" and 250,000 inhabitants of New Delhi have had to move from their homes. The holy city of Banares on the river Ganges has also been badly affected by the floods, which have damaged many buildings and roads, and swept away telephone and electricity lines. It is estimated that 15 million people in West Bengal have felt the impact of the disaster. Grave disaster Much of northern India's crops have been ruined and fresh water supplies contaminated. The Indian Air Force has been working to ensure that the worst affected areas are receiving the supplies they need, and aid agencies are standing by. The fear now is that typhoid and cholera will swiftly follow the floods. The chief minister of West Bengal said it was too early to count the deaths, but that this was one of the gravest disasters ever to hit the state. 


Flood and health factors

The large amount of pooled water remaining after the flood l leads to an increase in mosquito populations. Mosquitoes are most active at sunrise and sunset. People are exposed to malaria, dengu etc. 
Regardless of ones ability to swim. Swiftly moving shallow water can be deadly, and even shallow standing water can be dangerous for small children. Cars or other vehicles do not provide adequate protection from flood waters. Cars can be swept away or may break down in moving water. 

Many wild animals are forced from their natural habitats by flooding, and many domestic animals are also without homes after the flood. General public is exposed to rabies. Animals are disoriented and displaced, too. 
Rats may be a problem during and after a flood. Take care to secure all food supplies, and remove any animal carcasses in the vicinity by contacting MCD

Flood waters may can bury or moved hazardous chemical containers of solvents or other industrial chemicals from their normal storage places. Car batteries, even those in flood water, may still contain an electrical charge and should be removed with extreme caution by using insulated gloves. 
The dead animal if nor removed in time further pollute the atmosphere.
The displaced people would have lost every thing and needs to be provided with proper food shelter and financial support.

People from flood effected area return to their home after the flood water recedes. The following suggestions are provided for people returning to flood effected area:-


 When returning to a home that has been flooded use extreme caution, wear sturdy shoes and use flashlights when examining the building. Watch out for animals, bugs, and snakes that may have come into your home with the floodwater. Do not handle live electrical equipment in wet areas. Electrical equipment should be checked and dried before being return to service. Report broken utility lines to the proper authorities. If the pilot light went out on your natural gas furnace, hot water heater or stove, have it checked and corrected by qualified electrician. 

If your water is provided by a community water system that lost pressure during or following the flood, do not drink the water until it is determined to be safe. If your water is provided by a well and the well head was covered by floodwaters, you should have the water tested by Public Health officials and determined safe. If treatment is necessary, follow Public Health officials' directions. 

 If drinking water is not available, locate other sources of safe liquids, such as juices, soft drinks, or other beverages not exposed to flood waters. Other sources include water stored in clean, covered containers or water stored in a bathtub. 

 When electricity is lost for several hours, frozen and refrigerated food may not be safe to eat. Do not refreeze thawed food. Throw away all food that has been under water, except canned foods. Cans of foods should be washed and sanitized before opening. All food that cannot be saved should be double-bagged for normal disposal or buried at least two feet deep. 

 Be particularly careful to disinfect all surfaces that come into contact with food, i.e., countertops, pantry shelves, etc. 

 If there has been a back-flow of sewage into the home, wear rubber boots and gloves during cleanup. Remove and discard items that cannot be disinfected. 

 Pump out flooded basements gradually to avoid structural damage. 

 Stay out of buildings if floodwaters remain around the building. 

The destruction caused by the floods 

Worst destruction possibly in the history was the destruction of two cities

Two cities that lay at the edge of the Mediterranean more than 1,200 years ago, Herakleion and Eastern Canopus, disappeared suddenly, swallowed by the sea. Now, an international team of scientists may have figured out the mystery of why it happened. 

The researchers have concluded that the two cities collapsed when the land they were built on suddenly liquefied. Until recently, the only evidence that they existed came from Greek mythology and the writings of ancient historians. Then, during expeditions in 1999 and 2000, a team of French marine archaeologists headed by Franck Goddio found the
cities at the depths of 20 to 23 feet (6 to 7 meters) below the waters of Abu Qir Bay. The ruins of Eastern Canopus are nearly 1 mile (1.6 kilometers) east of the Aku Qir headland; Herakleion rests more than 3 miles (5.4 kilometers) from the shore. 
Stanley and his team studied cores from the seafloor, high-resolution seismic profiles, and the composition of the substrate-layers of mud, shell, silt, and sand deposited over time. From their analysis, they concluded that the cities fell when a flood caused the land to suddenly liquefy into mud. 
Two Arabic coins found at the site date from between A.D. 724 and 743. Written records that document a major flood of the Nile in A.D. 741 to 742 provide a framework for dating the disappearance of the two cities. There are no major earthquakes documented for this period. 
Significant flooding not only would cause the river banks to collapse, but also would bring heavy loads of sedimentation. This combined with the weight of the roiling water could have caused the soft, unstable mud on which the cities had been built to liquefy, Stanley and his colleagues argue in Volume 412 of the journal Nature. 
The authors note that similar processes have occurred at the mouth of the Mississippi River. 
"River mouths shift over time," Stanley explained. "It's been very common after bigger floods for the mouth of the Mississippi to change drastically. You have liquefaction, slumping riverbanks, and parts of land going up and down all over the place." 
 
Floods in Assam, Northeast India 

Floods in Bangladesh (center) give the impresssion that the Bay of Bengal (bottom) has decided to come ashore. Monsoon rains have innundated the region, causing rivers such as the Brahmaputra (flowing into the center of the image from the northeast) and the Ganges (flowing in at left center edge) to spill from their banks and flood low-lying areas. Half million people have been displaced by the flooding in the region. 
This Moderate Resolution Imaging Spectroradiometer (MODIS) image from the Terra satellite on July 5, 2003, shows standing water in dark blue, clouds in light blue, sunglint (glare) in white, and vegetation in green. 
Image courtesy Jesse Allen, based on data from the MODIS Rapid Response 

Damage due to Cyclone, Heavy Rains & Flood during - South- West Monsoon, 2003
(Provisional, As on 10-07-2003)

Here is a story on floods variants of the same are found in all countries

Once there was a worldwide flood, sent by God to judge the wickedness of man. But there was one righteous family which was forewarned of the coming flood. They built a boat on which they survived the flood along with the animals. As the flood ended, their boat landed on a high mountain from which they descended and repopulated the whole earth. 
Of course the story sounds much like the Biblical story of the great flood of Noah's day. The most similar accounts are typically from middle eastern cultures, but surprisingly similar legends are found in South America and the Pacific Islands and elsewhere. None of these stories contains the beauty, clarity, and believable detail given in the Bible, but each is meaningful to their own culture. 
Anthropologists will tell you that a myth is often the faded memory of a real event. Details may have been added, lost, or obscured in the telling and retelling, but the kernel of truth remains. When two separate cultures have the same "myth" in their body of folklore, their ancestors must have either experienced the same event, or they both descended from a common ancestral source which itself experienced the event. 
The only credible way to understand the widespread, similar flood legends is to recognize that all people living today, even though separated geographically, linguistically, and culturally, have descended from the few real people who survived a real global flood, on a real boat which eventually landed on a real mountain. Their descendants now fill the globe, never to forget the real event. 
But, of course, this is not the view of most modern scholars. They prefer to believe that something in our commonly evolved psyche forces each culture to invent the same imaginary flood legend with no basis in real history. Instead of scholarship, this is "willful ignorance" of the fact that "the world that then was, being overflowed with water, perished" (II Peter 3:5,6).

Flood and Economy

Flood effects many areas of national economy. Following are some of the areas needing attention from government bodies :-

Agricultural Flood Water Damage 
Urban Flood Water Damage 
F Commercial and Industrial
Flood Damage_Residential Properties
Flood Damage Transportation and Utilities
Crop and Pasture Damage
FlatLand

FLOOD FORECASTING NETWORK IN INDIA

Flood forecasting has been recognized as one of the most important, reliable and cost-effective non-structural measures for flood management. Recognizing the crucial role it can play, Central Water Commission, Ministry of Water Resources has set up a network of forecasting stations covering all important flood prone interstate rivers. The forecasts issued by these stations are used to alert the Public and to enable the administrative and engineering agencies of the States/UT's to take appropriate measures.

Central Water Commission started flood-forecasting services in 1958 with the setting up of its first forecasting station on Yamuna at Delhi Railway Bridge. At present Central Water Commission has network of 159 floods forecasting stations as below: -