Monsoon Forecast, floods and preparedness
In a forecast update in June 2017, the India Meteorological Department (IMD) forecasted higher monsoon rainfall during the year than its forecast in April 2017 because of favourable developments in global conditions, particularly the lower prospects of rain-busting El Nino conditions in the Pacific Ocean. IMD’s optimistic forecast was corroborated by the widely respected Australian weather office, which said the El Nino phenomenon, associated with abnormal warming of parts of the Pacific Ocean, had stopped developing, although it has still not been ruled out.
The updated forecast of 98% of normal rainfall was expected to bring cheer among farmers and policy makers. It is believed that if Monsoon would be better, it will help control food inflation, which is a key input in the Reserve Bank of India’s stance towards interest rates. The India Meteorological Department (IMD) also forecasted good monsoon activity in the crucial months of July and August, when rainfall casts the biggest influence on the growth of crops and output. But Monsoon also wrecks havoc by causing floods in some states of India.
Sixty persons have died due to the floods in Assam over the last couple of months. Nearly 10 lakh people in 21 districts of the State have been affected. The South Salwara district is the worst hit. The districts of Lakhimpur, Karimganj and Biswanath have also been severely affected by the flood. According to State officials, about 435 roads, seven bridges and 30 embankments have been damaged in the floods. Hundreds of houses were submerged as the Brahmaputra has been flowing above the danger level.
Assam Chief Minister Sarbananda Sonowal directed July 17 all Deputy Commissioners to ensure that families affected by the floods were provided with relief materials, irrespective of whether they were staying in relief camps or not. He asked authorities in the five districts covered by Kaziranga National Park — Nagaon, Karbi Anglong, Golaghat, Biswanath Chariali and Sonitpur — to take steps to safeguard wild animals affected by the floods in close cooperation with the police and the forest department.
The Assam State Disaster Management Authority said 1,102 villages were underwater at present and nearly 41,000 hectares of crop areas were inundated.
In Odisha, the State government rushed relief materials to villagers in the Rayagada and Kalahandi districts, a day after flash floods wrought havoc. About 4,000 people were evacuated and lodged in 15 temporary shelters, where cooked food was being provided to them at free kitchen centres. Five bridges were washed away and four major roads were damaged in the floods. The twin cities of Cuttack and Bhubaneswar faced heavy waterlogging. In 18 major localities in Cuttack, residents had a tough time stepping out of their houses as the lanes and by-lanes were submerged in water. Cuttack received 154.5 mm of rainfall over the 24 hours till July 17 morning.
Chief Minister Naveen Patnaik directed on July 17 all departments to work on a war-footing to restore road and power connectivity to the flood-hit villages. The flood-related death toll in Gujarat rose to 11 as two more persons died in the last 24 hours.
Other states are also facing the havoc of flood. Many parts of Gujarat are also facing difficulties due to flood. Rescue operations are on in Jamnagar district, where several people are still stranded. The Umergam and Kaprada taluks of Valsad district received the highest rainfall of 99 mm and 98 mm, respectively. West Bengal too received isolated heavy downpour. A man was swept away by flash floods triggered by a cloud burst in the Chama district of Himachal Pradesh, as rain lashed many parts of the State.
Understanding El Nino and La Nino
El Niño is the warm phase of the El Niño Southern Oscillation (ENSO) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific (between approximately the International Date Line and 120°W), including off the Pacific coast of South America. El Niño Southern Oscillation refers to the cycle of warm and cold temperatures, as measured by sea surface temperature, SST, of the tropical central and eastern Pacific Ocean. El Niño is accompanied by high air pressure in the western Pacific and low air pressure in the eastern Pacific. The cool phase of ENSO is called “La Niña” with SST in the eastern Pacific below average and air pressures high in the eastern and low in western Pacific. The ENSO cycle, both El Niño and La Niña, cause global changes of both temperatures and rainfall. The following picture depicts EL Nino.
Developing countries that are dependent upon agriculture and fishing, particularly those bordering the Pacific Ocean, are usually most affected. In American Spanish, the capitalized term “El Niño” refers to “the little boy”, so named because the pool of warm water in the Pacific near South America is often at its warmest around Christmas. The original name, “El Niño de Navidad”, traces its origin centuries back to Peruvian fishermen, who named the weather phenomenon in reference to the newborn Christ. “La Niña”, chosen as the ‘opposite’ of El Niño, literally translates to “the little girl”.
India’s weather forecasting system
The India Meteorological Department (IMD), also referred to as the Met Department, is an agency of the Ministry of Earth Sciences of the Government of India. It is the principal agency responsible for meteorological observations, weather forecasting and seismology. IMD is headquartered in New Delhi and operates hundreds of observation stations across India and Antarctica. IMD is also one of the six Regional Specialised Meteorological Centres of the World Meteorological Organization. It has the responsibility for forecasting, naming and distribution of warnings for tropical cyclones in the Northern Indian Ocean region, including the Malacca Straits, the Bay of Bengal, the Arabian Sea and the Persian Gulf.
Causes of flood
Floods are caused by many factors (or a combination of any of these): heavy rainfall, highly accelerated snowmelt, severe winds over water, unusual high tides, tsunamis, or failure of dams, levees, retention ponds, or other structures that retained the water. Flooding can be exacerbated by increased amounts of impervious surface or by other natural hazards such as wildfires, which reduce the supply of vegetation that can absorb rainfall.
Periodic floods occur on many rivers, forming a surrounding region known as the flood plain. During times of rain, some of the water is retained in ponds or soil, some is absorbed by grass and vegetation, some evaporates, and the rest travels over the land as surface runoff. Floods occur when ponds, lakes, riverbeds, soil, and vegetation cannot absorb all the water. Water then runs off the land in quantities that cannot be carried within stream channels or retained in natural ponds, lakes, and man-made reservoirs.
About 30 percent of all precipitation becomes runoff and that amount might be increased by water from melting snow. River flooding is often caused by heavy rain, sometimes increased by melting snow. A flood that rises rapidly, with little or no warning, is called a flash flood. Flash floods usually result from intense rainfall over a relatively small area, or if the area was already saturated from previous precipitation.
Flood Management in India
Flood control as a subject is not included in any of the legislative lists of India be it the Union List, the State List or the Concurrent List. However, embankment and drainage are mentioned specifically in Entry 17 of List II or the State List. Thus, it can basically be said that it is the state’s responsibility to deal with the floods. In fact, several states have already created laws that have the necessary provisions to deal with these issues, while the national government, in these cases, mainly plays the roles of an advisor, promoter, and catalyst.
The flood management mechanisms that exist in India at the moment is operational at two levels – central level and state level. The state level mechanism is made up of the water resource department, the Flood Control Board, and State Technical Advisory Committee. The central level mechanism is made up of bodies such as the Central Water Commission (CWC), the Farakka Barrage Project Authority, the Ganga Flood Control Commission, the National Disaster Management Authority, and the Brahmaputra Board. Over the years, the Indian Government has also taken the following initiatives in order to deal with floods:
- Policy Statement 1954
- National Flood Commission (Rashtriya Barh Ayog) 1980
- High Level Committee on Floods – 1957
- Expert Committee to Review the Implementation of the Recommendations of National Flood Commission – 2003 (R Rangachari Committee)
- Policy Statement of 1958
- National Water Policy (1987/2002/2012)
In general, the flood management measures that are being used in India can be broadly classified into engineering or structural measures and administrative or non-structural measures. The engineering measures comprise the following:
- Reservoirs
- Drainage improvement
- Embankments
- Diversion of flood waters
- Channelization of rivers
- Watershed management
- Channel improvement
The administrative measures can be broken up into flood plain zoning and flood proofing. The CWC also performs the responsibility of forecasting floods through the CWC National Flood Forecasting Network. The work of the various agencies, which are part of the central mechanism to manage floods in India, tends to differ from one another considering the unique challenges they face within their jurisdictions. The main responsibility of the Farakka Barrage Project Authority is to protect the river bank and make sure it is not eroded. Its area of jurisdiction is the area near the barrage.
On the other hand, the Central Water Commission, set up in 1945 by the national government, works toward developing more and better flood control measures, using, and conserving water resources, and promoting them as well. It also caters to areas like using water beneficially, in irrigation, and generating hydropower, apart from river conservation and flood management.
