Comprehensive Disaster Management Plan June’ 2014
Total Page:16
File Type:pdf, Size:1020Kb
DEPARTMENT OF WATER RESOURCES COMPREHENSIVE DISASTER MANAGEMENT PLAN (UPDATED STRATEGIC PLAN FOR DISASTER MANAGEMENT) MAHANADI- BURHABALANGA- PHAILIN-LEHAR-HELEN BRAHAMANI-BAITARANI SUBARNAREKHA JUNE’2014 SOMETIMES DISASTERS ARE INEVITABLE, BUT TIMELY TAKEN PRECAUTIONARY MEASURES AND POST DISASTER RESCUE AND REHABILITATION ACTIVITIES MINIMISES THE LOSS TO A GREATER EXTENT. THE REPORT DESCRIBES THE STRATEGIC PLANS FOR DISASTER MANAGEMENT BY STATE WATER RESOURCES DEPARTMENT. DEPARTMENT OF WATER RESOURCES GOVERNMENT OF ODISHA DEPARTMENT OF WATER RESOURCES, GOVERNMENT OF ODISHA COMPREHENSIVE DISASTER MANAGEMENT PLAN JUNE’ 2014 CONTENTS SL. TOPIC PAGE NO. NO. 1.0 INTRODUCTION 1.1 GENERAL 1 1.2 PROBABLE REASONS 3 2.0 FLOOD AS A DISASTER AND ITS MANAGEMENT 2.1 GENERAL 4 2.2 MAJOR FLOODS 5 3.0 FLOOD MANAGEMENT IN ODISHA-PREVENTIVE MEASURES 3.1 GENERAL 6 3.2 FLOOD CONTROL IN MAHANADI BASIN 7 3.3 FLOOD CONTROL IN BAITARANI BASIN 9 3.4 FLOOD CONTROL IN BRAHMANI BASIN 11 3.5 MEASURES 12 3.5.1 Structural Measures 12 3.5.2 Non-Structural Measures 13 3.5.3 Institution and Community 14 3.6 DUTIES AND RESPONSIBILITY OF OFFICERS 14 3.6.1 JE/AE in Flood Management 15 3.6.1.1 Pre-flood Measures 15 3.6.1.2 Measures during flood 16 3.6.1.3 Post flood measures 16 3.6.1.4 General 17 3.6.2 Assistant Executive Engineer (AEE) 17 3.6.2.1 Pre-flood Measures 17 3.6.2.2 Measures during flood 18 3.6.2.3 Post flood measures 19 3.6.2.4 General 19 3.6.3 Executive Engineer (EE) 19 3.6.3.1 Pre-flood Measures 19 3.6.3.2 Measures during flood 20 3.6.3.3 Post flood measures 20 3.6.3.4 General 20 3.6.4 Superintending Engineer 21 3.6.5 Chief Engineer/ Chief Engineer & Basin Manager 23 3.7 FORMAT FOR FLOOD DAMAGE REPORT 23 3.8 RISK ANALYSIS 24 3.8.1 Assessing Flood Probabilities 24 3.8.2 Flood Modelling of Rivers 24 3.8.3 Storm surge Modelling for Hurricanes and Cyclones 24 4.FLOOD CONTROL-MITIGATION MEASURES 4.1 FLOOD DAMAGE STATISTICS 25 4.2 FLOOD FIGHTING 25 4.2.1 Measures taken during Phailin’2013 26 4.2.2 Vulnerable Locations for 2013 33 4.3 RAINFALL DISTRIBUTION 36 5.0 PREPAREDNESS FOR THE CURRENT YEAR 5.1 GENERAL 38 5.2 ACTIVITIES 38 5.3 DISASTER PREPAREDNESS FOR THE YEAR’2014 WITH 40 EXPERIENCE FROM PHAILIN’2013 5.4 PHYSICAL ACTION TO BE TAKEN BY OFFICIAL 44 5.5 LONG TERM ACTIONS AND RESPONSIBILITIES 48 5.6 SCIENTIFIC ASSESSMENT OF FLOOD PRONE AREAS- PILOT 49 PROJECT AT BURHABALANGA BASIN 5.7 KNOWLEDGE MANAGEMENT 50 5.8 POINTS FOR OPEN DISCUSSIONS 50 5.8.1 Embankment Free Flood Plain 50 5.8.2 De-commissioning of Older Dams 51 FIGURE SL. NO. FIGURE NO. PAGE NO. 1.1 Basin Map with State Boundary 1 3.1 Mahanadi Basin 7 3.2 Rule Curve of Hirakud 8 3.3 Baitarani Basin 10 3.4 Brahmani Basin 12 4.1 Flood Affected Districts 2008 25 4.2 Flood Inundation Map of 14th Sept.2011 26 4.3 Tracks of Phailin in different days 28 4.4 Flood Inundation Map of 18th Oct.2013 32 4.5 Position of Vulnerable Location 34 4.6 Deviation of Rainfall from Normal 37 5.1 Tentative Vulnerable Location of 2014 40 5.2 Burhabalanga Basin 49 TABLE SL. NO. TABLE NO. PAGE NO. 1.1 Basin Details of Odisha 2 2.2 Major Flood Events of Odisha 5 3.1 Travel time of flood water in Mahanadi Basin 8 3.2 1 and 2-Day rainfall maxima as a function of area 11 4.1 Flood Damage Statistics 25 4.2 Gauge Positions during Phailin 27 4.3 Reservoir pre and post Depletion Llevels 28 4.4 Damage details during Phailin 33 4.5 List of Vulnerable Locations of the all the Basins 34 - 1. 1.0 INTRODUCTION 1.1 GENERAL: The state Odisha is vulnerable to multiple disasters. Due to its topography, river networks, sub-tropical littoral location, the State is prone to heavy floods, tropical cyclone forced rainfall and storm surges. The state has 11 river basins (Fig.1.1) and the basin details are given in Table 1.1. Its densely populated coastal plains are the alluvial deposits of its river systems. The rivers in these areas with heavy load of silt have very little carrying capacity, resulting in frequent floods, only to be compounded by breached embankments. The state is ranked as the 5th most flood prone state of the country after UP, Bihar, Assam and West Bengal with a flood prone area of 33400 km2. The south-west monsoon brings rains to the state from June to September every year. The state receives an average annual rainfall of 1500 mm and more than 80% of it occurs during monsoon period only. The coastal districts of the state are more vulnerable to frequent low pressure, cyclonic storms, depression and deep depression. It is a fact that the three major river systems Mahanadi, Brahmani and Baitarani forms a single delta during high flood and in most of the cases the flood water of these three systems blend together causing considerable flood havoc. Besides the state has 476.40 kms of coastline on the west of Bay of Bengal. The flood problem becomes more severe when the flood synchronies with high tides causing slow recede of flood. The silt deposited regularly by the streams in the delta area raises the bed level and the rivers often overflow their banks due to reduction in its carrying capacity. Fig. 1.1 Basin Map with State Boundary 1 Table 1.1 Basin Details of Odisha Total Catchment Catchment Catchme Area Area Name of the nt area within Outside Major Tributaries Basin (In sq. Odisha Odisha km.) (in sq.km.) (in sq.km.) Mahanadi 141134 65628 75506 Ib, Jeera, Ong, Tel, Brutang, Manjore Karandijore, Hariharjore, Surubalijore Brahmani 39269 22516 16753 Sankh, Koel, Gohira, Tikira, Samakoi, Ramiala Baitarani 14218 13482 736 Deo, Kanjhari, Kusei, Salandi Burhabalanga 4838 4838 0 Sunei, Kalo, Katra, Sana N. Subernarekha 19277 2983 16294 Kharkhai R. Rushikulya 8963 8963 0 Badanadi, Dhanei, Ghodahado, Padma, Baghua Vansadhara 11377 8960 2417 Badanalla, Harbhangi Mahendratanaya, Sananadi. Nagavali 9275 4500 4775 Jhanjabati, Sananadi, Barha Nadi Situguda N. Indravati 41700 7400 34300 Kapur, Muran, Telengiri, Joura, Turi, Bhaskel Kolab 20427 10300 10127 Karandi N., Potteru R., Sileru R.,Machhkund R. Bahuda 1118 890 228 Poichandia, Boginadi, Batruda Nalla 2 1.2 PROBABLE REASONS: The flood problem in the state generally aggravated due to some or all of the reasons as below: Erratic monsoon, heavy monsoon rainfall accompanied by low pressures, depressions, deep depressions and cyclones. Dam releases due to heavy inflows, thus causing massive outflows in the river. Inadequate channel carrying capacity due to low height embankment. Low rate of discharge of floodwater into the sea due to congestion of river mouths. Tidal surge during the flood thereby heading up of floodwater. This may occur during monsoon or non-monsoon. Changing land use conditions leading to the erosion of soils, thus reducing the channel carrying and reservoir capacity. Thick clay layer mostly over deltaic area (paddy grown area) which form an impervious bed. Free flow flood plains are gradually being closed due to public utility/demand causing excess floodwater in the rivers, which ultimately threats to the capital embankments. 3 2. FLOOD AS A DISASTER AND ITS MANAGEMENT 2.1GENERAL: The flood disaster and its management may be dealt in 3 basic steps such as: Prevention Mitigation Preparedness Generally in prevention measures are being taken to prevent the flood and flood related hazards whereas in mitigation we try to minimize the losses as much as possible. In preparedness the steps are being taken to fight for the forthcoming flood. The state has five major river basins namely Mahanadi, Brahmani, Baitarani, Subarnarekha and Rushikulya out of eleven, which cause high floods in their respective deltas. The rivers like Vamshadhara and Burhabalang also cause flash floods due to instant runoff from their hilly catchment. In Mahanadi system after commissioning of Hirakud dam during 1958, the flood miseries have been reduced considerably in its delta. However still it continues either due to dam releases from Hirakud reservoir or due to flow contributions from intercepted catchments of over 50,000 sq. km. down below Hirakud dam project and upto delta. In Mahanadi system, mostly the rivers Kathjori, Devi, Kuakhai, Kushabhadra, Daya, Bhargabi, Birupa, Chitroptala, Paika drains most of the floodwater in to the sea. Other storage projects like Rengali, Kolab, Indravati, Salandi are also controlling the floods in the respective rivers to a greater extent. However the flood hazard is still not under control and generally every two to three year a heavy flood is experienced in the deltaic area. Due to excess of water than carrying capacity, major breaches occurred on these rivers and almost inundate the deltaic area. 4 2.2 MAJOR FLOODS: Some of the major flood events that occurred in recent past are shown in Table 2.2. Table 2.2 Major Flood Events of Odisha Sl. Year Month of River Area No. Occurrence affected Lakh (ha) 1 1980 September Mahanadi, Brahmani, Baitarani & 3.19 Vamsadhara July - 2 1982 Mahanadi, Rushikulya 12.0 August July- Mahanadi, Brahmani,Baitarani, 3 2001 7.99 October Subarnarekha, Burhabalang, Vamsadhara, Rushikulya & Indravati July- Mahanadi, Brahmani, Baitarani 4 2003 5.03 October Subarnarekha, Burhabalang, Vamsadhara, Rushikulya & Indravati July - Baitarani, Mahanadi, Rushikulya, 5 2006 3.04 August Vamsadhara, Burhabalang & Indravati 6 2008 September Mahanadi, Brahmani, Baitarani 4.59 7 2011 September Mahanadi Source: Flood Management Manual (2008) DOWR up to Sl.