Dangers of dam burst as seen in the recent past

Dangers of dam burst as seen in the recent past

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Dr Latha Anantha
One of history’s worst dam bursts took place in Gujarat in 1979 when the four-kilometer long Machhu Dam II on the Machhu River collapsed. This led to a deluge in the industrial city of Morbi located five kilometers downstream as well as surrounding rural areas destroying thousands of homes and lives. While this was a tragedy, it was by no means an isolated one. Over forty dam bursts have taken place in India, and there have been other events that have shown that earthquake hazard continues to be a serious threat to dams. These disasters have raised concerns over the issue of dam safety and design of the 4900 large dams and the several thousand small dams in India. These dams add up to a key responsibility in terms of asset management and safety.Yet, not much has been done to assure dam safety since the Machhu Dam burst.
This has raised a few questions. How does the Dam Safety Organisation sustain existing dam structures? Are there dam safety norms to be followed? Latha Anantha, River Research Centre, Thrissur talks to India Water Portal on some of these issues.
What can you tell us about the threat of dam bursts?
In the 20th century, around 200 notable dam failures have occurred in the world killing about 8000 people. Some of the big catastrophes include the accident in Vaiont, Italy killing 2600 people; the Machhu Dam in India gave way in 1979 killing 2000 people. The other dam failures in India include Kaddam (1957), Panshet (1961), Khadakwasla (1961), Chikkhole (1962) and Nanak Sagar (1967). The failure of the Malpasset Dam in France in 1959 killed 421 people and the Buffalo Creek dam in USA in 1972 claimed 125 lives. The long term safety of a dam depends upon the degradation of its materials, weakening of foundation and seismology issues to name a few.
The Mullaperiyar issue should have become the forerunner to put in place a comprehensive Dam Safety Act given the large number of dams that have crossed the 50 year lifespan which is the viable age of a dam as per international standards.
Which institutions are involved in assuring dam safety? Is a law on dam safety norms that would put in place good practices and procedures on safety parameters of large dams in the offing?
A Dam Safety Organisation was set up in the Central Water Commission way back in 1979 with state level dam safety organisations in 12 states under its guidance. Kerala is one of them. Meanwhile, while Bihar has its own Dam Safety Law, India is yet to have a comprehensive, legally binding accountability mechanism in case of dam failures, or clear norms on dam safety. The Dam Safety Bill was introduced in the Lok Sabha in 2010 August. However, it is yet to be discussed or taken up by the Government of India with the seriousness it deserves. It should be noted here that several politicians from Tamil Nadu had opposed the Bill claiming that it would harm the State’s interest, clearly with Mullaperiyar and Parambikulam Aliyar dams in mind.
Does the bill relate dam safety with environmental impacts?
The Bill does not contain any norms that relate dam safety with environmental impacts. While dam safety remains the domain of the Ministry of Water Resources (MoWR), it does not touch upon the environmental impacts, both upstream and downstream, in case of faulty performances, lack of proper sediment flush outs, sudden flooding of downstream due to uncontrolled releases of impounded water, dam failure etc. In other words, the Ministry of Environment and Forests (MoEF), which grants environmental and forest clearance to dam projects, does not have a role when it comes to dam safety related issues impinging upon the river ecology or livelihoods dependent upon rivers.
The Bill lacks any clause for accountability of dam owner/ custodian towards environmental damage and wildlife caused by dam failures. It does not consider compensation in the form of eco restoration measures as the responsibility of the dam owner / custodian either, in the eventuality of a catastrophe.
Please tell us about the implementation of the World Bank-funded Dam Rehabilitation and Improvement Project (DRIP).  Kerala was one of the four states in which this was implemented and 19 dams, barrages and regulators of the Irrigation Department and 12 projects of the State Electricity Board are expected to be covered.
Since 2010, the Central Water Commission has embarked upon a World Bank funded Dam Rehabilitation and Improvement Project with the stated objectives of
1.    improving the safety and operational performance of selected existing dams in India through their rehabilitation and
2.    improving central and state-level institutional capacity to sustainably manage dam safety administration and operation and maintenance.
The Central Water Commission introductory document on the same admits that of the 4711 large dams completed and 390 under construction, 3750 (79.6%) dams are more than 20 years old (1). Many large dams are ageing and have various structural deficiencies and shortcomings in operation and monitoring facilities. Few of them do not meet the present design standards – both structurally and hydrologically. Thus an increasing number of dams fall in the category where they need rehabilitation.
DRIP is a follow up to the earlier Dam Safety Assurance & Rehabilitation Project (DSARP) assisted by the World Bank implemented in 4 States namely Madhya Pradesh, Orissa, Rajasthan and Tamil Nadu, under the overall guidance of the Central Water Commission during the period 1991 to 1999. The Project was completed in September 1999 at a cost of Rs. 422.95 crore. The total investment for the DRIP project as per latest figures is Rs.2100 crore (2).
Out of the 223 dams selected in the five states, 31 are from Kerala (12 hydro power projects and 19 Major Irrigation Projects). The projects covered by the Kerala State Electricity Board KSEB include Kerala Sholayar and Poringalkuthu (Chalakudy river), Sabarigiri (Pamba river), Sengulam, Idukki, Pallivasal, Idamalayar, Neriyamangalam (Periyar) etc. Hydrological assessments, emergency preparedness plans, development of emergency warning system, public awareness campaigns, arresting of seepages and floodplain mapping are some of the main components of the plan. As for the implementation of the DRIP objectives in Kerala, the bidding process for the rehabilitation works is just underway.
Has the implementation of Dam Rehabilitation and Improvement Project (DRIP) been satisfactory?
Though the Project was supposed to be completed by 2016, the closing date has been extended to 2018 by the World Bank. The track record of implementation is not satisfactory. Tamil Nadu with the highest number of dams for the DRIP package has just 4 percent achievement against the target while Kerala’s is just over 9 percent (Rs. 8.1 crore spent out of Rs. 86 crore allotted) to date (3). It is interesting to note that even the dams built since the 1990s like the Chimoni Irrigation Project, Gavi, Moozhiyar (HEPs) etc., are included in the list indicative of the fact that even the new dams are having safety and performance issues. The leaks from Chimony dam commissioned in 1996 had started immediately after the dam became operational! While the Parambikulam group of dams (which are part of Kerala river systems but diverted to Tamil Nadu by Parambikulam Aliyar Treaty) are included in the list of projects by Tamil Nadu, curiously Mullaperiyar which is the oldest among the dams does not figure in the list. Is it because Tamil Nadu wants to show that Mullaperiyar is safe and fit? However, the DRIP project component for Tamil Nadu includes sedimentation studies in 60 dams and catchment area works in Kundah and Krishnagiri projects.
Monitoring committees including the affected communities / local self governments need to be set up as part of institutional capacity building. Studies should also be initiated with the participation of the downstream communities on probable socio-economic-cultural and environmental impacts in case of dam failure taking sample cases across the country.
Meanwhile, the World Bank Review Report on DRIP dated May 28, 2015 notes that the overall implementation progress of the projects is ‘Moderately Unsatisfactory’ (4).
Please tell us about the institutional aspects. Is civil society being consulted in any way? Has their awareness about dam safety issues and their capacity to diagnose and prioritise problems improved?
Dam safety related discussions and plans still remain within the government and technocratic circles. Kerala has a 13 member Dam Safety Authority (KSDA) led by a retired Judge. As per the Kerala Irrigation and Water Conservation Act 2003 (Amendment 2006), KSDA is supposed to inspect the age, geological and seismic factors of the dam, conduct periodic inspection of the dams, advice the Government on security measures to be adopted, direct the custodian of the dam to carry out alteration, improvement, replacement or strengthening measures if need be, to direct the custodian to decommission or suspend the functioning of any dam in case of threat to life or property, to advice the government on policies and procedures to be followed to name a few. However, there is nothing within the Act that makes it mandatory for the KSDA to hold consultations with the people living downstream of dams or local self governments or civil society groups on issues of dam safety/ rehabilitation as well as include them in the disaster management operations in case of emergency due to floods or dam breaches. This is a major lacuna of the Act.
Dam safety also relates to the downstream impacts on human life, properties and natural life and the river ecosystem in the eventuality of a dam failure. However, the Act leans heavily on structural safety aspects-related precautions and does not look into the responsibility and fixing accountability on the dam custodian with respect to the impacts on the downstream population, river ecology and environment in case of dam failure.
What about the dam safety aspects of Mullaperiyar?
The Mullaperiyar dam is a classic example. The repeated alarms raised by the downstream communities over the rising water levels in the Mullaperiyar reservoir across several monsoons has triggered lots of debates and discussions on how to tackle dam breaches or leakages among the downstream local self governments and civil society groups including the Mullaperiyar Samrakshana Samithi. In 2011 when the water level rose to 136 ft and beyond, control rooms were opened by the Government for helping people in case of emergency. The emergency actions should have been followed by setting up of permanent ‘Peoples Monitoring Committees’ for each local self government sufficiently empowered to train and alert the downstream communities, update the dam authorities and carry out disaster management efforts in cases of emergency.
The Mullaperiyar dam has indeed cast a shadow of fear and social insecurity among the people in the downstream panchayats. Several meetings have been held in Idukki and Ernakulam districts by civil society groups to discuss the means to raise awareness amongst the local self governments downstream of the Idukki and Mullaperiyar dam on the need to step up surveillance, measures to tackle emergency situations. Submissions have been given to the authorities on the need to step up awareness and train people on emergency preparedness. Door to door campaigns have been initiated by the Church and social and cultural groups to create awareness among the people on the safety measures to be taken and to avoid panic.
Kerala’s Disaster Management Plan Profile (2014) admits that ‘As many of the dams in the state have exceeded their design life, they are potentially disastrous to people living in the downstream’. It is time Kerala had a Comprehensive Disaster Management Plan in place on dams starting with the 120 year old Mullaperiyar dam with the involvement of the local self governments, experts and civil society groups who know the area and the possible impacts. A preliminary disaster management plan prepared by a three-member team of scientists in 2007, as per the instruction of the then revenue minister K P Rajendran, is gathering dust. The Plan should be an integrated effort of the Ministries of Water Resources, Revenue, Environment and Climate Change among others.
What about dam decommissioning?
Some of the oldest dams in the world exist in India but dam decommissioning is a widely debated subject. Demands for decommissioning have already been raised for the Mullaperiyar dam, Dumbur dam over the Gumti River in Tripura and Jaikawadi Dam in Maharashtra in different contexts by civil society groups and independent experts. Estimates reveal that around 100 large dams are more than 100 years old and more than 400 large dams between 50-100 years old. The purview of dam safety should be expanded to include dam decommissioning as an option on a case by case basis to ensure long term safety of the people and safeguard the environment. A critical issue like Dam Safety should be brought out of the Ministry of Water Resources-Central Water Commission domain and should entail co-ordination of all the different relevant Ministries, civil society groups, independent experts/ institutions and people.
(Dr Latha Anantha is Director, River Research Centre, Ollur.P.O. Kerala, India)

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