Chennai floods

1Wednesday, May 3, 2023 Alwin Memorial Senior Secondary School

Floods !!!

CHENNAI FLOODS

Wednesday, May 3, 2023 Alwin Memorial Senior Secondary School 3

INTRODUCTION

A depression formed over southwest Bay of Bengal on 8th November, 2015 morning, moved North-East wards at a speed of 15 kmph storm and intensified into a deep depression and lay centred at 0530 hours IST on 9th November 2015 over southwest Bay of Bengal near latitude 11.5°N and longitude 80.7°N, about 110 km east-southeast of Pondicherry and 180 km southeast of Chennai. It moved North-East wards and crossed North Tamil Nadu coast near Puducherry from 12.00 noon on 10 th November between Puducherry and Cuddalore up to 7.30 PM the same day. Under the influence of this system, heavy to very heavy rainfall occurred over many parts of Tamil Nadu and other characteristic are described below. The rainfall started from 8th Morning and intensified in the evening of the same day and continued till the evening of 9th November in many places. Cuddalore and Pondicherry witnessed heavy rains. Chennai also received substantial rains. The process of the Heavy Rains put the people/communities out of gear for the whole day and report coming from Cuddalore and Pondicherry indicate that rains are still continuing in some places though less in intensity.


Depression formed over southwest Bay of Bengal moved North-East wards at a speed of 15 kmph storm and intensified into a deep depression. Under the influence of this system, heavy to very heavy rainfall occurred over many parts of Tamil Nadu Chennai also received substantial rains. The process of the Heavy Rains put the people/communities out of gear for the whole day and report coming from Cuddalore and Pondicherry indicate that rains are still continuing in some places though less in intensity. Chennai received a rainfall of 25cm within 24 Hours.


SOIL DATA OF CHENNAI• The geology of Chennai comprises mostly clay, shale and sandstone.

The city is classified into three regions based on geology, sandy areas, clayey areas and hard-rock areas. Sandy areas are found along the river banks and the coasts. Clayey regions cover most of the city. Hard rock areas are Guindy, Velachery, Adambakkam and a part of Saidapet.In sandy areas such as Tiruvanmiyur, Adyar, Kottivakkam, Santhome, George Town, Tondiarpet and the rest of coastal Chennai, rainwater run-off percolates very quickly. In clayey and hard rock areas, rainwater percolates slowly, but it is held by the soil for a longer time. The city's clayey areas include T. Nagar, West Mambalam, Anna Nagar, Perambur and Virugambakkam.


Soil Classifications.Hydrologic part is much controlled by different types of soils. Soils are classified by taking their color, texture, fertilities and

chemical combinations includes salts, minerals and the solution effect over them. As far as the agricultural and groundwater point of view, the soil types of the study area are described based on the thematic maps collected.

Entisols: These are alluvial soils comprising sand and sandy materials occurring on the beaches and at the confluence of rivers

and by the side of the rivers & channels. Because of their permeability, these soils while being good storehouses of groundwater are not fit for cultivation. These are found along coastal belt in small strips, eastern part of Ponneri Taluk, south of Pulicat Lake to Ennore Creek, south of Cooum confluence to Adyar Estuary and Thiruvanmiyur - Covelong stretch, throughout the length of beach of the Eastern Coast.

Inceptisols: This major soil group consists of the red sandy to brownish clayey soil fragments derived from parent rock and is

spread all along the westward side of the East Coast Road. The Inceptisols are suitable for agricultural hold moderate groundwater reserves. Systematic water bearing rocks are bordering this type and percolate more water into these soil formations for effective agriculture. The agricultural pattern in this type of soils is intensive.

Vertisols: The Vertisols are clayey in nature with high specific water retention capacity but poor in supporting agriculture. These

are found as groundmass in extreme northern portion around Gummidipoondi, Ponneri, Minjur, Madhavaram, and Manali and in the western portion of the East Coast Road around Thiruporur. Hydrogeologically Vertisols is grouped under Aquitard. The age of these formations of soils is of Tertiary. The capacity of water bearing and yielding character of this type is null and void. The Valudhavoor patches of clay and the Manali, Mathur clayey soils are the significant members of this type of soil. Vertisols are exclusively used for dwelling and other industrial locals only. The rate of infiltration varies from 1 to 3 cm / hr for fine red sandy clay, clayey sand, sandy clay, sand fine to medium, sand medium to coarse and very coarse and gravel and for weathered rock, fractured and jointed rock it varies from 0.2 to 0.5 cm / hr. which normally occur in the study area


S.No.

TEXTURE

PERCENTAGE OF SPECIFIC YIELD

1 Clay 01 – 102 Red Sandy 10 – 303 Red Gravely Sandy 15 – 304 Sand And Gravel (Red) 15 – 255 Thick Plastic Clay 05 – 106 Kankar / Gondwana formation /

Weathered Rock02 – 05

7 Fractured & Jointed Rock 01 – 05

S.No.

TEXTURE

INFILTRATION RATE IN CM / HR.

1 Coarse sand (River sandy) 2.0 to 252 Fine Sandy (River Sandy) 1.3 to 2.03 Fine sandy Loam (Red Sandy) / Sandstone

M – C1.0 to 1.2

4 Silty Loam 0.8 to 1.05 Clay Loam 0.6 to 0.86 Clay 0.5 to 0.67 Coarse Sandy (Red Sandy) Gravely 2.5 to 3.08 Kankar / Gondwana Siltstone / Weathered

Rock0.5 to 0.6

9 Fractured & Jointed Rock 0.2 to 0.5


Heavy Rainfall:• NEVYELI : 45cm • CHIDAMBARAM : 21cm • VRIDDHACHALAM : 13cm • KOLLIDEM : 10cm• Chennai - Average : 14 cm

AMBATTUR :20cm

• MAMALLAPURAM : 17cm • POONAMALLEE : 17 cm • MEENAMBAKAM : 17 cm • TARAMANI : 15 cm • KOLAPAKAM : 15cm • NUNGAMBAKAM : 6cm • MEENAMBAKAM : 4cm

• Tirupattur : 16 cm• Vellore : 8 cm


AVERAGE RAINFALL IN CHENNAI BETWEEN 2005 – 2015• Unprecedented heavy Chennai rains, followed by Chennai floods, marked

the beginning of December this year. After wrecking havoc on the residents of the capital city of Tamil Nadu for almost a month in November, back to back systems in the Bay of Bengal continued to give torrential rain over the city in December as well, resulting in a flood like situation over many areas of the state.

• Chennai has so far received 539 mm of rain in December as against the monthly average of 191 mm. Chennai rain in December was almost 3 times more than the normal rainfall in December. It has also broken the record of last ten years when the capital city received 421 mm of rain in 2005.



Latitude Longitude

1 Sholingar 13 07 00 79 26 00 445 391 31 84 952

2 Ramakrishnarajpet 13.167 79.439 362 320 13 79 773

3 Pallipet 13.336 79.442 404 361 19 111 895

4 Minnal 13 05 00 79 33 00 445 398 361 91 959

5 Arakonam 13 05 00 79 40 00 468 479 43 80 1070

6 Kesavaram 13 02 00 79 46 00 484 486 18 92 1080

7 Poondi 13 11 50 79 53 00 601 600 27 65 1292

8 Thiruvallore 13.135 79.911 424 545 46 73 1088

9 Chembarambakkam 13 07 00 79 55 00 418 620 24 83 1145

10 Sriperumbudur 12.967 79.792 418 547 36 66 1068

11 Tamaraipakkam Anicut 13 12 00 80 12 00 420 619 26 67 1131

12 Tambaram 12 55 00 80 07 00 513 809 22 80 1424

13 Poonthamallee 13 02 00 80 07 00 408 702 49 64 1223

14 Sholavaram 13 14 00 80 10 00 438 733 26 91 1289

15 Meenambakkam 13 00 00 80 11 00 433 768 37 86 1324

16 Redhills 13 10 00 80 11 00 342 614 24 90 1070

17 Korattur Anicut 13 05 30 79 59 30 402 543 24 72 1041

18 Ponneri 13 19 30 80 12 00 361 749 45 69 1223

19 Saidapet 13 03 00 80 14 00 405 759 52 70 1286

20 Nungambakkam 13 04 00 80 15 00 363 750 43 60 1215

21 Valliyur 13 12 50 79 59 15 409 720 30 103 1262

22 Athipet 13 15 38 80 17 00 328 750 42 56 1176

23 Chepauk 13 04 00 80 16 00 378 622 26 86 1112

24 Tiruthani 13 09 20 70 32 40 456 466 44 82 1047

25 Thiruvetriyur * 13.133 80.283 355 707 56 14 1132

26 Tharamani * 12 59 30 80 14 55 489 789 41 58 1377

27 Kaveripakkam 12 54 00 79 29 00 431 927 33 80 1471

28 Panappakkam 12 56 00 79 36 00 508 416 36 125 1085

29 Thiruvalangadu * 13.167 79.75 534 651 42 56 1283

30 Pattabiramam * 13.12 80.11 490 572 48 57 1167

31 Elavur 13 29 00 80 09 00 434 694 48 26 1202

Details Of Rainfall Stations and 50 Years normal average Rainfall

S.No. Name of the RF Station

SWM NEM Winter Summer

Note: * These Rainfall Stations were installed during recent years, and average has been arrived only for actiual years of data available.

AnnualCoordinates


S.No.

District

District Area in Sq.

Km.

District Area falling in the basin in Sq. Km.

Percentage of

Area in the Basin

Percentage of District Area with reference to

Basin Area.

1 Chennai 174 174 100 3.12 Thiruvallore and

Kanjeepuram * 7857

4275

54.4

77.1

3 Vellore 6077 1093 17.98 19.8

Total 14,108 5,542 100

S. No.

Region Location Average Annual Rainfall in mm

1

Hilly Region

SholingarTiruthaniPallipet

9521047895

2

Plain Region

ThiruvalloreSholavaramMinnalPoondiArakonam

10881289959

12921070

3

Coastal Region

TambaramMeenambakkamSaidapetNungambakkamChepauk.

14241324128612151112



CONSEQUENCES OF CHENNAI FLOOD-2015• Supplies of basic necessities, including milk, water and

vegetables, were affected due to logistical difficulties. During the December floods in Chennai and the adjoining areas, milk packets sold for 100 (US$1.50), five times more than their usual cost. Water bottles and cans were sold at prices between 100 (US$1.50) to 150 (US$2.20). Vegetables were sold at least 10 (15¢ US) to 20 (30¢ US) over and above their normal average cost at the wholesale level.


CONSEQUENCES OF CHENNAI FLOOD-2015• Apart from basic necessities, fuel supplies and travel were greatly affected, especially in

Chennai. Numerous accounts of price-gouging were reported; airfares to and from for most parts of South India peaked to almost 10 times over their normal price. A round trip fare from Mumbai or New Delhi to Bangalore (the nearest city to Chennai) was sold by airlines like Jet Airways at rates of almost 1 lakh (US$1,500), a trip which would have ordinarily cost between 10,000 (US$150) to 20,000 (US$300).Apart from airfares in South India, airfares also increased for other connections within the country, due to disruptions in rail services. In response, the Ministry of Civil Aviation warned companies against taking advantage of the situation to overcharge and that it would intervene if any of the passenger flight carriers did so. On its own, the civil aviation ministry also operated flights from the Rajali naval airbase in Arakonam, Chennai with a fixed price of 2,000 (US$30) per passenger for travel to the northern states and 1,000 (US$15) per passenger for travel to the southern states.


CONSEQUENCES OF CHENNAI FLOOD-2015• In Chennai, over 1.5 lakh (150,000) street vendors sustained losses of over 300 crore (US$45 million).The persistent

rainfall and flooding forced several major automakers in the region, including Ford, Renault, Nissan and Daimler AG, to temporarily halt production, resulting in estimated losses of up to 1000 crore (US$149 million). Industry analysts estimated total industrial losses as a result of the floods to be in the range of 10,000 to 15,000 crore (US$1.52 billion to US$2.27 billion). All of the major auto- and truck-makers in the Oragadam and Sriperumbudur manufacturing belts resumed operations by 8 December, despite ongoing damage assessments; some employees were forced to continue working from their homes. Many major information technology companies, including Infosys and Tata Consultancy Services, closed their offices and had their employees work from their homes, or transferred operations to other locations in cities including Pune and Bengaluru. Prices of vegetables and fruits significantly increased, as over 50% of supplies were affected after numerous lorries were stranded. The Indian Oil Corporation was forced to close its large Manali refinery in Chennai because of the floods. Popular television networks, namely Puthiya Thalaimurai, Jaya TV and Mega TV halted services following flood-related technical difficulties. Motorcycle producer Royal Enfield shut its Chennai offices on 1 December, as well as its plants in Thiruvotriyur and Oragadam, which had already lost the production of 4,000 motorcycles in November. The Chennai real estate market sustained an estimated loss of nearly 30000 crore (US$4.5 billion),while over 20,000 small and medium industrial units across Tamil Nadu reported total losses of over 14000 crore (US$2.1 billion).


CONSEQUENCES OF CHENNAI FLOOD-2015• Insurers in India estimated they would receive claims totalling over 1000

crore (US$150 million) for losses to property, cargo and inventory, mostly from auto companies. During the first period of floods, claims worth about 500 crore (US$75 million) were settled by various general insurance companies in India, largely from shopkeepers and vehicle owners. According to the General Insurance Corporation of India, another large amount of claims was expected to be reported by automobile companies based in South India. The General Insurance giant of India, the New India Assurance alone received claims amounting about 425 crore (US$63 million) from about 1,700 claims submissions till mid December.


CONSEQUENCES OF CHENNAI FLOOD-2015• Several Indian IT giants like Tata Consultancy Services and Wipro also

informed their stake holders about an expected material impact on its third-quarter earnings due to the floods and then to the low volume revenue during Christmas and New Year holidays in the west. Car makers were also hugely affected due to shut down of plants, thus leading to lower production volume. German automaker BMW expected to resume production only from January 2016 while the American auto maker Ford started its plant only in late December 2015. The estimated production loss cost of BMW was about 250 crore (US$37 million) and Ford's was about 600 crore (US$90 million).


CONSEQUENCES OF CHENNAI FLOOD-2015• Improper design and maintenance of drainage systems• Media reports stated the Chennai Corporation had ignored September warnings of above-

average monsoonal rains issued by the Indian Meteorological Department, and that extensive and costly projects begun in 2013 to desilt city storm drains had been ineffectively conducted. The drains themselves were reported to have been shoddily built and improperly designed. A 2014 CAG report revealed that a diversion channel from the Buckingham canal near Okkiyum Maduvu to the sea (a drain project under the JNNURM scheme) could have saved South Chennai from flooding; the government, however, dropped the 100 crore scheme, which, had it been completed, would have drained floodwater from southern neighbourhood at a rate of 3,500 cubic feet per second. The 2014 CAG report said the defective planning of flood control projects caused delays and increased costs, defeating the objective of the scheme. "The fact is that alleviation of inundation of flood water in Chennai city remains largely unachieved", it said.


CONSEQUENCES OF CHENNAI FLOOD-2015• Climate-change related• Union Environment and Forests Minister Javadekar said the exact causes of the flooding -

whether the result of climate change or stemming from other causes - remained in “a grey area” as experts had differing opinions. Regarding the current floods, he said the United Nations would not deem the evidence conclusive enough to be able to reach a judgment. "One thing is sure, climate change brings such disasters more frequently. So [the] frequency, the ferocity of untimely rains increases, along with erratic monsoons, droughts and floods; all these are caused [by climate change].” he said. He subsequently clarified his position on the Tamil Nadu floods in a written statement addressed to the Rajya Sabha. According to Javadekar, the recent extreme rainfall across the region was "highly localised" and could not be definitively attributed to the effects of climate-change. “The extreme rainfall that occurred over the coastal districts of Tamil Nadu is part of the natural variability of the Indian monsoon system. Although some studies have reported an increase in frequency and intensity of extremes in rainfall during the past 40-50 years, their attribution to global warming is not established.” Javadekar said the Inter-Governmental Panel on Climate Change (IPCC) and local assessments have indicated that extreme rainfall events will likely increase in frequency by the end of the 21st century.

• In 2006, a study by the Indian Institute of Tropical Meteorology (IITM) in Pune showed extreme precipitation events had increased in frequency and intensity in India over the period from 1950 to the 2000s; while CSE’s climate change experts recommend detailed attribution studies to establish more links between the Chennai floods and climate change, they did state that existing scientific studies establish a possible connection.


NO PROPER FOOD REQUIREMENTS


DEPELETION OF FUELS


REASON FOR FLOOD• Unregulated urban planning and illegal construction• Union Minister for Environment and Forests Prakash Javadekar termed the Chennai floods a "natural

disaster of unprecedented scale", and said it provided lessons to improve urban planning and improve city governance. "Chennai gives a lesson, and we must learn from this lesson and improve our urban planning and improve city governance, which is very essential." He also criticised the Chennai Corporation for not having done enough "to remove all encroachments. Unless you allow the drains to flow freely to the sea, water will be clogged and that is what has unfortunately happened.”

• Sunita Narain, the director of the Centre for Science and Environment (CSE) think tank, said the unprecedented floods in the Chennai metropolitan region were the direct result of unregulated urbanisation. According to Narain, "our urban sprawls such as Delhi, Kolkata, Mumbai, Chennai, Srinagar, etc., have not paid adequate attention to the natural water bodies that exist in them. In Chennai, each of its lakes has a natural flood discharge channel which drains the spillover. But we have built over many of these water bodies, blocking the smooth flow of water. We have forgotten the art of drainage. We only see land for buildings, not for water." According to research conducted by CSE, Chennai had over 600 lakes in the 1980s, but a master plan published in 2008 showed only a fraction of them to be in a healthy condition. State records have shown the total area of 19 major lakes shrank from 1,130 hectares in the 1980s to around 645 hectares in the early 2000s, reducing their storage capacity. Drains carrying surplus water from tanks to other wetlands have also been encroached upon, while city storm water drains are clogged and require immediate desilting. Chennai has only 855 km of stormwater drains against 2,847 km of urban roads, resulting in flooding after even a marginally heavy downpour.


RIVERS AFFECTED IN FLOOD

• The Cooum River is the shortest classified river draining into the Bay of Bengal. This river is about 72 km in length, flowing 32 km in the Urban part and the rest in rural part. The river is highly polluted in the urban area (Chennai), which we can call as "Polluted Part of the Cooum River", and the rest as "Unpolluted Part of the Cooum River". Along with the Adyar River running parallel to the south, the river trifurcates the city and separates Northern Chennai from Central Chennai.

• Its source is in a place by the same name 'Cooum' or 'Koovam' in Tiruvallur district adjoining Chennai district.• The classification of Unpolluted Vs Polluted Part:• Polluted Part: Paruthipattu Anaikat to the River Mouth in Bay of Bengal. Unpolluted Part: The Origin in the Cooum

Village to Paruthipattu Anaikat.• In Chennai district, the river flows through three corporation zones—Kilpauk, Nungambakkam and Triplicane—for a

total length of 16 kilometres (10 mi).• Owing to intensive use of surface water upstream for agriculture, indiscriminate pumping of groundwater leading to

reduced base flow in the river, formation of sand bar at the mouth of the river, discharge of untreated sewage and industrial effluents and encroachment along the banks, the river, especially the downstream, has been highly polluted.


RIVERS AFFECTED IN FLOOD

• Adyar or Adayar, originating near the Chembarambakkam Lake in Kanchipuram district, is one of the two rivers which winds through Chennai (Madras), Tamil Nadu, India, and joins the Bay of Bengal at the Adyar Estuary. The 42.5-kilometre (26.4 mi) long river contributes to the estuarine ecosystem of Chennai. Despite the high pollution levels, boating and fishing take place in this river. The river collects surplus water from about 200 tanks and lakes, small streams and the rainwater drains in the city, with a combined catchment area of 860 square kilometres (331 sq mi). Most of the waste from the city is drained into this river and the Cooum


EMERGENCY COMMUNICATION CENTRE

• IRCS-TNB services were also duly informed to our Chairman. Thereafter Chairman has instructed to assign our office Phone No.044 – 28554548 to the Relief Callers and also exclusively assign two staff of IRCS-TNB for requesting Relief Calls Throughout day and night. Soon after receiving relief calls, immediately they have to communicate to the DM Rescue Team.

• On knowing IRCS-TNB DM Rescue services by the Govt. of Tamil Nadu ( Health Department ) of our Emergency Call Number 044 – 28554548 have been communicated to Corporation of Chennai, Fire & Rescue Department & 108 Emergency Call Centre for any rescue Services.



SECONDARY LAKES OF CHENNAI• Chembarambakkam lake • Cholavaram lake• Poondi lake• Puzhal lake• Ambattur lake• Chetpet lake • Velachery lake

• Chitlapakkam lake• Korattur lake• Manali lake• Mangal lake• Porur lake• Retteri lake


FLOOD RESCUE AND EVACUATION OPERATIONS

• Montieth Road, Egmore - Heavy Rain Water Stagnation in the Road and Break Down STC Bus.

• Due to heavy rain the entire stretch of Montieth Road, Egmore flooded with water and IRCS-TNB staff members regulated the traffic jam on 14.11.2015.


SRIPERAMBUDUR BHOPAL ERI DAMAGE On 14.11.2015 Bhopal Eri at Sriperambudur was broken which

caused heavy flood water flushed out from the Eri. Three Children from the same locality was drowned and washed away from the flood water. Hearing about the news IRCS-TNB staff immediately rushed to the spot for rendering services. The fire and Rescue Department Officials were also present and due to heavy water flow they are enable to search the bodies of the Children and only after the normalcy of the situation, drowned bodies can be searched and hence they returned back.


P R E PA R AT I O N O F M A K E S H I F T R A F T



HUMAN CHAIN USED TO EVACUATE THE AFFECTED PEOPLE FROM FLOOD




EVACUATION OF DEAD BODIES


RESCUING THE PATIENTS FROM THE GOVT. HOSPITAL TAMBARAM




POLITICAL LEADERS HELPING PEOPLE DURING

FLOOD


CELEBRITIES SHOWING THE ORIGINAL HEROISM


CELEBRITIES SHOWING THE ORIGINAL HEROISM


THE THREE TALES OF MISERY


DAMAGES IN THE HOSPITALSMany hospitals and primary health centres are affected by this flood.In a private hospital [ MIOT] nearly 14 people were dead due to the insufficient supply of oxygen to the patients. Apart from that, the flood water gushed into the scanning and X-ray lab.This led to the death, this could have been prevented by shifting the patients to other hospitals as MIOT hospital is in a low-lying area.Many people complain that why they have no supply of current and oxygen as MIOT is one of the famous hospital for the treatment of cancer in Tamilnadu.


FREE MEDICAL CAMP BEING ORGANIZED




REASONS FOR THIS FLOOD (VIDEO)


•We hope that Chennai will recover soon!!!


THE END

By: Deepu Kishore. A

Hariharan.kShivaram Sriramulu