Cyclones in the Bay of Bengal hit the city. ----Chennai accounts to frequent flash floods due to consistent increase in the amount of rainfall brought to city area by cyclones.
Chennai city does not havemuch of green space, except the Guindy National Park with an area of 270.57 hectares,which is under reserve forest category.
North Chennai is primarily an industrial area. Central Chennai is the commercial heart of the city. South & West Chennai, previously mostlyresidential, are now becoming commercial with upcoming firms & call centres. The city is fast expanding in the south & in the west.-----It is estimated that more than half of the wetlands have been converted for other uses. Many of the water bodies, green cover and natural depressions have disappeared due to the human induced successions as it is filled with wastes or developments/encroachments and become flood prone areas
Majority of solid wastes are dumped in a mixed form in low lying areas & in open areas by Chennai Corporation. The area of 19 major lakes has been shrunk from a total of 1,130hectares to nearly 645 hectares and hence reduced storage capacity.
The Hyogo Framework for Action (HFA) 2005-2012: Building the Resilience of Nations and Communities to Disasters was signed in 2005 by members of the United Nations; it calls for local and internationalsociety to join forces to significantly reduce loss of lives and social, economic and environmentalassets when hazards strike….and asian urban cities being less explored in the resiliency domain---this programme turns out to be an important base for knowledge sharing…
Initially, rating scale has been constructed and weight has been assigned subjectively based on how the city officials perceive the vulnerability of each variable by comparing them one by one….. Each dimension (natural, physical, social, economic, institutional) correspond to various variables (Table 1) through which their respective scores are calculated.
Higher values of resilience are equivalent to higher preparedness to cope with climate and disasters and inversely. Policy points and recommendations are based on the results, and provide encouragement of city governments. engagements in specific cist services, institution and capacity building.
The city governments were asked to set their CDRI targets through self assessment matrix, and this could be measurable over a period of 1 year (short‐term), 2‐3 years (medium‐term), and 5‐10 years (long‐term).
To boost the DRR activities at local level ..the individual wards volunteers are encouraged to come forward with improved disaster preparedness and mitigation measures…..the disaster responses in city are useful assets for city’s relief operations.
HFA------Making disater risk reduction a priorityImproving risk information and early warning.Building a culture of safety and resilienceReducing the risks in key sectorsStrengthening preparedness for response.
In order to help the financially not-so sound local bodies to carry out at least essential infrastructure improvements, CMDA has worked out the schemescalled as Local Bodies Assistance Programme (LAP) which is being implemented since 1983, andCommunity Based Environment Development (CBED) Programme which is being implementedsince 2003.
reveals spread oftemple tanks in the entire Chennai most of which are degraded now and inefficient in controlling floods orstoring water.
.(60% revenue generation in state-fromkochi
Urban Flood Risk Reduction by Resiliency Planning
“URBAN FLOOD RISK REDUCTIONBY RESILIENCY PLANNING”Presented By, Remya PanickerUnder the guidance of Asst. Prof. Sameer DeshkarM.Tech 4TH SEM- Urban Planning V.N.I.T,Nagpur
CONTENTS• CASE STUDY- Chennai, India.• Best practice- CBED programme. Chennai• INTODUCTION TO STUDY AREA----•Cochin, Kerala.
“Applying a Climate Disaster Resilience Index (CDRI) toenhance planning decisions in Chennai, IndiaBy: Ramasamy Krishnamurthy (UoM),Jonas Joerin (Kyoto University), Rajib Shaw (Kyoto University), Yukiko Takeuchi (KyotoUniversity)CASE STUDY:
Urban Disaster Risk in ChennaiStudy locationThe capital of Tamil Nadu ,Chennai isthe fourth largest Metropolitan city inIndia .Tier I city-Largest city in south(urban population)It is divided into 4 parts –North, central, South & West.The city is known for its Hindu temples.It is a major trade center, being welllinked by road, rail and air to importantcities besides being a sea port.
Causes of Chennai floods-from literature study :CHENNAIFLOODFACTORSDirect factorsIndirect FactorsIncrease inrainfall TopographyUrbanisationInadequate& poordrainagesystems Disposal ofsolid waste& otherdebrisVehicleparkingon roadsDue to globalclimate change& urban heatisland effect•Construction oftransportation networks allalong major water courses•Increase in concrete spaces-decrease in open spaces.Plain terrainlacking naturalgradient forfree run-off•Insufficient sewerage capacity•Heavy siltation along drainagechannels•Lack of coordination between theagencies•People’sattitude•Lack of mgt.measures byauthority•Increase inconcretespaces(3-4%)•Discrepanciesbetweenpublic andlocal authority
Chennai City (176km2)Urbanisation :Current population (2011):4.68 million,• Population growth:1971‐2001:---1.72%/year2001‐2011:--0.75%/yearMigrant population –accounted to22% of Chennai’s populationin 2001.• Population density (avg):26,597 (p/km2)•Chennai Metropolitan Areaexpected at 9.9 million inhabitantsby 2025.01020304050ChennaiCityMunicipalityTownPanchayatGrowth of population in CMA- 1971-200102468Other partsof T.NOther partsin IndiaOtherCountriesMigration to Chennai City 1961-2001Demographic Stress :PopulationInLakhsYear
Urban DisasterRisks in Chennai:ShocksEarthquakes-moderate damage zone-(seismic zone 3)Cyclones- Veryheavy rains causingfloods.Strong winds.Storm surge.Floods-localized,(majordrains, low lyingareas,water,canals)36 flood hotspots(2005 floods)Cooum riverAdyar riverChennai is a multihazard prone area;Adyar riverCoastal Reach 0.0 – 6.4 kmCentral City Reach 6.4 – 9.3 kmOuter City Reach 9.3 – 20.0 kmCoastal Reach 0.0 – 4.2 kmCentral City Reach 4.2 – 12.2 kmOuter City Reach 12.2 – 24.7 km
Urban Disaster Risks in Chennai:Shocks– 2005, 2008 and 2010flash floods were causedby cyclone causinggreat damage.– Cyclone is activemostly during themonths of October toDecember.-Cyclones 1959‐2008 innorth part of TamilNadu State:-28 cyclones in 50 years
Nilam, October, 2012Key characteristics: -100boats wentmissing,4 died,6 missing.Around 150 Uprooted trees and torrentialrains hampered smooth flow of traffic.Nisha,November, 2008Key characteristics:86 died, damage toroad, rail networks.‐Floods triggered through heavystorms, cyclone.Jal, December, 2010Key characteristics:‐ Floods triggered through, cyclone.‐ More than 170 casualties in T.NThane, December, 2011Key characteristics: localised flooding.-No loss to life. Traffic seriously disrupted.Recent CYCLONE Events- ShocksNilamThaneJalNishaCatastrophic floods experienced inpast-2005,1998,1996,1985,1976
Chennaicity limitsMetropolitanlimits54.257.095.1718.482.090.570.4711.89City-land use ResidentialCommercialIndustrialInstitutionalopen space/recreationagriculturenon-urbanothers(vacant,forest,hills,water bodies,lowlying..etc)21.870.376.283.010.1911.922.3354.03Land use- Rest of CMAResidentialCommercialIndustrialInstitutionalOpenspace/recreationAgricultureNon urbanOthersUrban DisasterRisks in Chennai ‐StressesSource: www.cdmachennai.gov.inChennai City (172km2)Metropolitan- (400km2)
Urbanisation :0100200300400500600 19711981199120011973-Urban area1983-Urban area1993-Urban area2006-Urban areaDensity(personsperurbanized)HectareDistance from city center (Km)Citycore0%10%20%30%40%50%1971198119912001%oftotalhousingstockDistance from city centre-KmLand use change-1997-2006
Expected water supply gapfor 2026- 3OO MLD-CMAAbout 650 small and big water bodies inand around the city has been reduced toless than 30. Also, the ground water levelcame down up to 10m within 5 years.Urban infrastructure stress:Water sector..The sewage system originally designed forabout 6.5 lakhs population at 114 LPCD ofwater supply.---modified during 1989-91even then it has not reached the requiredcapacity.Sewerage sector..Total waste water outfalls inwater ways accounts to 85%.Inadequacy of storm-water drainagesystem (flat terrain) and lack ofmaintenance.Drainage sector..The city has only 855 km ofstorm drains against 2847km of urban roads.The highest per capita solidwaste generation in India is inChennai (0.6kg/day).Solid waste mgt..Even though there is a proper system ofcollection, segregation & disposal ofwastes, The Attitude of people isappalling causing the pile of solid wastesin the vicinity of the residential areasitself.
Under- Global COEprogrammeCDRI capacity buildingprogrammeGraphical Community disaster resilience framework
Climate Disaster Resilience Index in Chennai :Methodology“My city is getting ready”CDRI tool: 5 x 5 matrixStage 1: Capacity building of city govt. officials to complete aCDRI questionnaire to create a overall resilience mapping
Table1- Dimensions and variables considered for CDRI analysis
Stage 2: Training & action workshop, to design a self-evaluation matrix andto initiate Climate action planning .Figure: Sample of CDRI Self assessment matrix to monitor future adaptation activities in city
Enhancing the Resilience of Chennai to Climate‐related DisastersResultImplementationof in CAPFormaladoption of CAPFormulation ofactionsAssessmentClimate Action Plan (CAP)Policy–CDRI, localcharacteristicsand feasibility; focus onnon‐structural measures(soft adaptation)–Draft formulated inDecember 2010 incollaboration with theCorporation of Chennaiand University of Madras.– In progress of adoptionby the Corporation ofChennaiPositive outcome:….Safer Chennai Campaign-Launched on 19th August 2010 to support Chennai’sparticipation at the 2010‐11 “World DisasterReduction Campaign: Making Cities Resilient“from the United Nations– Provides an opportunity to support and establishmulti‐stakeholder dialogues to decisivelyimplement actions enhancing the resilience in Chennai.– The CDRI is an example of a process‐orientedresearch approach: from assessment to planning andimplementation.Stage.3- Initiatingdevelopment of the CAPand implementationprocess.
Way Forward – Assessing Climate‐related DisasterResilience at the Micro‐levelHouseholds located in the vicinity ofrivers and canals have higher damagesfrom floods!
Best practice :CMA-Community Based Environment Development Programme(CBED) 2003(a) enable the participation of the community at the grassroots level to identifyand prioritize environment-related issues affecting all sections of thecommunity,(b) To ensure full stakeholder participation including the elected representatives,(c) To create a common platform for the community to work together to solvethe local issues which will be unique to the respective areas, in the manner that isacceptable to all stakeholders,(d) To help in capacity building at the local level to plan, coordinate and formulatefeasible / bankable project proposals with emphasis on environmentalconsiderations, multi-sectoral coordination and effective participation ofpublic and private sectors and(e) To ensure better maintenance and utilization of the assets created and to developspirit of ownership amidst the beneficiaries.PROGRAMME OBJECTIVES :
Programme are,(a) Improvement to the existing parks / playfield(b) Improvement to the existing burial / burning grounds(c) Desilting of lakes / ponds / tanks to augment water supply and improve theground water table(d) Rain water harvesting and tree planting(e) Construction / renovation of toilets and other environmental improvements inthe government schools(f) Solid Waste Management(g) Construction of storm water drains(h) Construction of common utility buildings and(i) Any other projects with an objective to improve the localenvironmentEnvironmental projects funded under CBEDFinancial assistance :80% CMDA10% community10% local body
Temple tanks in ChennaiSource: CPREEC,2008Number of Temple tanks- 50Degradation of lake MadhuravayalDandishwar temple tank,Velachery
A few Tank renovation works underCBED with CMDA Grant Assistance:
Introduction to study area :•The largest agglomeration in Kerala.• Nerve center of all commercial and economic activitiesin the state of Kerala.•Tier-II city.City population-2011-6,01,574.Metropolitan population-2011-2.1 Million.•The coastal areas densely populated with a density of6300 persons per sq.km. in the city compared to theaverage density of 819 persons per sq.km. in theState.•Has a flat terrain and a large expanse of backwaters andcanals with small and large islands scattered in thebackwaters.•The economy of the area is dependent on the activitiesof the Kochi Port.•A number of industries are located in this district andthe proximity and development potential of Kochi Portattracts private and public investments in portrelated activities.CoC area-94.88KmGCDA area-537.12Km
Identification of issues:KEY ISSUES OF WATER SUPPLY :• Gap between demand and supply –397 mld;(w.r.t2036 demand)• Intermittent water supply – limited from ½ anhour a day to 8 hours. Twice a week only incertain areas;• Non-availability of local spot sources due tosalinity;• Distant perennial sources - makes water supplycostly;• The availability of water in the 2 rivers may not besufficient in the long run; and• Salinity of the environment causes corrosion ofpipes.• Lack of Coverage –only 5% of the corporationarea is covered serving only 20,000 people;• Old and dilapidated Sewage Treatment Plants;• No Revenue – No monthly billing;• High water table – septic tanks, two pit latrines, etc.do not function properly;• High cost of sewerage –flat terrain makesnatural gravitational flow difficult; the soil ismainly loose sand and clay, making opencutting difficult. High water table necessitatessewage-pumping stations at frequent intervals; and• Within the urban areas, residential and otheractivities are so densely located, that the septictank system does not work leading to water and soilpollution.KEY ISSUES OF Sewerage:• Poor waste collection system;• Poor frequency of waste collection;• Inefficient collection and disposal at temporary transfer locations;• Obsolete waste handling and transportation system;• No scientific and modern waste processing at any stage;• Water logging due to choking of drains with waste;• Mosquito menace due to stagnation of water in drains;• Misery of the poor who are the worst affected due to poor waste Management.KEY ISSUES OF SWM:Key Issues Of drainage:• Inadequate drainage –only60% of the KochiCorporation area iscovered by drainage leadingto frequent flooding of roads;• Inefficient system – The flatterrain of the region, highwater table and the nearness tosea make the tidal waterflow inwards;• Lack of a comprehensivedrainage Master Plan;• Barriers to drainage –Railway lines; and• Lack of proper co-ordination– In Kerala, provision ofdrainage is carried out by theconcerned local bodies, StateIrrigationDepartment, NationalHighway, Southern Railwaysand the State PWD. Lack ofproper co-ordination amongthese agencies leaves gaps inthis sector.Hydrological factors:•Ground water level•Presence of highimpervious cover•High tide impedingdrainage•Flat topograpgy-6m(elevation)Meteorologicalfactors:•Excessive rainfall-(8months in a year.)•Cyclonic storms•Localized rainfallHuman factors:•Surface sealing•Inefficiency of drainageinfrastructure•Disposal of solid waste indrains•Encroachment on floodplains.Causes of floods in Cochincanal can be smelled from three blocks awayand are breeding grounds for mosquitoes.Many of the smaller canals have beenconstricted by encroachments, and very littlewater flow occurs (except during floods).Low-Lying Islands I: These are already veryclose to sea levels and are vulnerable to sea-level rise.Low-Lying Islands II: Some of the islands aresettled, protected from high-tide sea level bylow sea-walls (“bunds”).
Inferences:•Urban areas being the most complex systems…requires greaterattention in all the 5 dimensions in unison to tackle the flood menace.•Resiliency development is the new way in URR.•Community Resiliency planning will help develop betterunique, location based flood risk management plans.•Problems with major flood management strategies is that theyfunction in piece meal manner and not address the issue in totality.•The floods are likely to rise…the question lies in how prepared we arein coping with it and overcoming it with the least possible losses tothe various players in the urban domain.
References :E sources:• www.cmdachennai.gov.in• www.ekm.kerala.gov.in• www.corporationofcochin.net•“Chennai Urban Land Market Assessment”-David E. Dowall and Paavo Monkkonen•“Urban floods in Bangalore and Chennai: risk management challenges and lessonsfor sustainable urban ecology”-Anil K. Gupta* and Sreeja S. Nair•“Mapping of Landuse/Landcover Changes of Chennai Coast and Issues related toCoastal Environment Using Remote Sensing and GIS”-Santhiya.G, Lakshumanan.C, Muthukumar.S, International journal of geomatics andgeosciences ,Volume 1, No 3, 2010.•“Human Development Report”- By Centre for Development StudiesThiruvananthapuram. (2005)•“Possible Vulnerabilities of Cochin, India,to Climate Change Impacts and ResponseStrategies to Increase Resilience-Cochin University of Science of Technology, U.S.Agency for International Development. (June 2003)