Andaman and Nicobar: A Challenge for Multi Hazard Risk Management

By: Sugata Hazra
Andaman and Nicobar Islands are multi hazard prone region. The policy interventions and measures taken in the area should recognise the vulnerable nature of the Islands to ensure a safer life for its people and its bio-diversity.
Disaster Events

On April 11, 2012 the Andaman Islands were rocked again by an earthquake of 8.9 Richter magnitude. The siren for tsunami warning went off in Port Blair along with a TV broadcast. Around 1500 people were evacuated from low lying areas of Kamrota, Nancowry, Katchal, Car Nicobar and Great Nicobar islands. Forest staff at Indira Point were also evacuated and tsunami alerts were sent through radio and mobile phones to fishermen out in the seas. Yes, the situation is different now, and appreciably so, from what it was in 2004 when over 10,000 helpless persons lost their lives in the Indian Ocean tsunami. However, the 2012 tsunami was not to happen and the tsunami warning was finally withdrawn with relief. The disaster preparedness of the islands with many mock drills, after the enactment of the Disaster Management Act, 2005, passed the litmus test. But a closer inspection revealed that no tsunami warning could be heard at the coasts and no mechanism was in place under the Emergency Operation Centre to alert the vulnerable coastal population – apart from the coast guards. Even the health centres and hospitals were not prepared to tackle a mass emergency situation which would arise after a devastating earthquake or tsunami.

The Andaman and Nicobar islands, with nearly half a million people are extremely vulnerable to high intensity earthquake and tsunamis, evidenced from the historical data and paleo-tsunami records. More than 20 earthquakes above a 6.5 richter magnitude and three tsunamis (1847,1881,1941) played havoc on the islands during the past 150 years before 2004. When we know that several active fault zones pass through the islands and surrounding ocean basins, are we adequately equipped for emergency action? We need to assess area-wise inundation risk; create earthquake hazard zonation maps; and, undertake a multi hazard risk assessment with available infrastructure and population bases for putting in place a scientific emergency action process. The subsidence and faulting, associated with the 2004 mega thrust earthquake, inundated a large portion of the coastal agricultural land, coconut plantation and mangroves. Water is yet to recede from several such submerged areas and farmers are yet to receive compensation. Thus, relief rehabilitation with insurances and instant compensation should be an integral part of a disaster management system.

It is to the credit of the Indian National Center for Ocean Information Services (INCOIS), we now have a tsunami warning system with regular ocean state forecasts for the Indian Ocean. But the island community is demanding the installation of Doppler weather radars at Port Blair, Corbin’s Cove, Dinglipur and Campbel to serve as early warning for cyclone and super cyclone events like ‘Thane’ of 2012 which killed several fishermen off the Andaman Seas, damaged fishing boats and stranded tourists in remote regions. The probability of future high intensity super cyclones such as ‘Laila’, ‘Giri’, or ‘Thane’ occurring in quick succession is extremely high, especially in a changing climatic regime. Andaman and Nicobar islands are a multi hazard prone area. A heavy shower fluidised the mud, which resulted in a landslide, bringing down a dairy farm – from the hill slope on to the road in May 2012. Though there were no casualties and no significant loss to infrastructure, land slide hazard zonation mapping with appropriate risk reduction mechanism would definitely minimise the future disaster risk in vulnerable areas.

Apart from natural disasters, threat from manmade disasters – oil spill and illegal coral mining looms large over the island system. Close proximity to the Malacca Strait, the international tanker route south of Indira Point at Great Nicobar, or the sea route of 10o Channel that holds the rich and diverse ecosystem of Andaman and Nicobar islands are extremely susceptible to the hazards of accidental oil spills. On January 21, 1993, a collision between two super tankers Mearsk Navigator with 2 million barrels of oil and Sanko Honours spilled 40,000 tonnes of crude oil which spread over 8000 sq nautical miles. Due to wind, the spill drifted towards Nicobar. The Indian coast guard launched a massive control and clean up operation using dispersant slick broom, deploying ships and helicopters – at a cost of Rs 13 crores. However, what is not known is how much damage was claimed by the Indian authorities from the tanker owners to compensate for the environmental deterioration. Even nine months after the spill, a group of scientists from the National Institute of Oceanography, Goa reported higher abundance of oleophilic and heterotrophic micro organism indicating existence of remnant spills at greater depths. Again on August 14, 2006, a small collision between Indian vessel Amar and a Japanese tanker Mitsu OSK caused a minor spill of 4500 tonnes of light crude. These statistics show how vulnerable the world’s second richest coralline ecosystem in the Bay of Bengal is to oil spill disasters. On April 16, 2008, residents discovered a thick layer of high speed diesel had engulfed the entire coastline of Chatham Port. This time, the cause was illegal discharge. The possibility of oil spill with intensifying petroleum exploration in the Andaman Sea opens up another risk horizon. While the emergency operation and contingency planning with respect to oil spills are quite efficient in the Andamans, we need to think of advanced preparedness planning such as the ‘Barrier against Spills’ as practised in Norway, to safeguard the ecosystem of Andaman Nicobar from impending disaster.

On another note, we usually orient our preparation against the rapid onset of disasters – earthquake, tsunami, cyclone, storm surges, oil spill or accidents which have little forewarning but also have limited impact over space and time. In the process we tend to overlook the slow onset of disasters such as water famine; climate change; and, sea level rise which actually offers enough and a longer forewarning period. The impacts are often irreversible – and a different kind of preparedness planning needs to be in place to combat it. The only source of potable water in sediment starved Andaman Nicobar group of islands is groundwater within the rocky regolith which has limited storage capacity in the benevolently showered Islands (~ 3000 mm annually). Already shortage of potable water is prevalent over many parts of the islands and instances of people suffering from water shortage are rising in the Islands. In an analysis it was projected that the present supply of potable water would need to be trebled by 2025 to meet the burgeoning demand. But the large scale water harvesting schemes – Dhanikhari Dam project, revival of Dilthaman tank, Chouldhari Scheme, and the yet to be completed Rutland water project, initiated in 2007 etc., are inherently dependent on the northeast monsoon rainfall which in turns depends upon climatic variability. It is time that desalination plants, as those already commissioned at Chennai, or Kavaratti, Lakshadweep – even solar desalination, considering the freely available solar irradiation in the order of 5.2 to 5.6 kW/m2 /day is made available in this tropical archipelago.

Although the average elevation of the Andaman and Nicobar island system is 40 m, low lying beach areas, mangrove swamps and coastal tracts of Chidyatappu-Burma nalla, Corbyns Cove Beach, southern point of South Andaman, Betapur Fisher Colony or similar areas are suffering from continuing coastal erosion due to the rising sea. An analysis using Topex, Poseidon and Jasson1 satellite altimetry data suggests that the rate of sea level rise in the period 2004-2009 is around 8 mm/year (between 5o-25oN, 80o-100oE) which is significantly higher than the global average of 3.14 mm/year.

This part of Indian Ocean is showing a significant rise of sea surface temperature – 0.04-0.05oC/year. A recent report brought by Ministry of Environment and Forests, Government of India projects that by 2030, the surface air temperature may rise by 1.7o to 2o C. This is not good news for corals and island communities of Andaman and Nicobar or south east Asia. After the world’s worst coral bleaching of 1998, the region had suffered another catastrophe in 2010 as reported by National Oceanic and Atmospheric Administration (NOAA) that nearly wiped out 80 per cent of the some of the species of corals of the Andaman Sea. The reef system so far is resilient and can recover again in a favourable regime. But it is like continuing business as usual – despite being on the verge of an ecological disaster. Multi hazard risk assessment and planned risk reduction approach is necessary for the Islands. While the Disaster Management Act, action plan for climate change and coastal zone regulation operate simultaneously for identification and risk reduction of vulnerable zones, there are serious gaps in cross sectoral coordination between multiple operating agencies. Disaster management also poses a challenge when we think of integrating the community, particularly the tribal community with the process of disaster preparedness. It may be of significance to note that among the four Negrito and two Mongoloid tribes of the islands – the Nicobarese bore the greatest casualty of the Indian Ocean Tsunami of 2004.

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