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Dam Safety Can No Longer Be Ignored

Dam safety can no longer be ignored

In order to have high standards of dam safety, the prerequisites are designing and constructing dams with reasonable safety margins; operating and maintaining them safely; and having emergency arrangements to address situations that might arise. Operation of a dam within its ambit also includes a thorough understanding of likely impacts and its management in case of flooding, in any emergency situation or in the event of dam failure, both upstream and downstream on communities living there, their livelihoods and also on infrastructure and property which can get affected. In fact, in many countries like Sweden and in many states of the US, a dam is assigned a dam safety class i.e. A, B or C depending upon the significance of the damage that might occur in case of dam failure, class A being assigned to dams whose failure might cause significant loss of public life and property. Dam safety requirements are calibrated accordingly and a higher burden is put on dam owners of higher class, concerning safety management system, emergency plans, overall assessments, and annual dam safety reporting.

In November 2020, the Central Water Commission (CWC) issued guidelines for classifying the hazard potential of dams to identify those projects whose failure or disruption could potentially lead to most severe consequences and to assist dam authorities to take appropriate measures to deal with such critical issues. ‘Hazard classification’, as per these guidelines, is based on four major categories: the capital value of the project, potential for loss of life, the potential for property damage and potential for environmental and cultural impact. Class IV is the most vulnerable and hazard-prone dam and this categorisation is solely based on the potential consequences to downstream life, properties, services and environment that would result from a failure or mis-operation of the dam.

The safety of a dam facility is a combined function of the technical systems, information management, the organisation and the people responsible for operating the systems. A good dam safety law therefore should be able to regulate all these aspects adequately. It is important to mention that in order to effectively manage the consequences in case a dam failure occurs or there is an emergency due to unprecedented flooding, apart from having a robust dam safety law, efficacy of regulation of certain other parameters are also equally important. Land use in flood plain zones in the downstream of dams, catchment area treatment plans, preparedness of disaster management authorities and its coordination with other district administration authorities — all these become extremely relevant and important factors.

In the US, ‘hazard creep’ is an acknowledged problem which occurs when new development downstream of an existing dam increases the hazard rating of the dam. The design flood requirements are typically based on the downstream hazard classification existing at the time of permitting and constructing the dam. The standard requirement in most US states is no development in a 1-in-100 year flood zone area. Alternatives to minimise or avoid this problem include linking dam safety and floodplain regulations to limit the extent of future hazard creep, or purchase of downstream flowage easements to prevent future development. Hazard creep cannot be ignored; it must be considered and controlled. Many states in the US have either dam safety and flood plain regulations combined or they work in close association with each other. We do not have any mandate for dam safety officials to work with flood plain managers in our country. In fact, in India, this species of flood plain managers does not even exist. As such, there is no clarity as to who is even responsible for demarcating these areas in the absence of a clear mandate in this regard. Implementation and evolution of dam safety norms and development in the downstream flood plains happen in every Indian state independently of each other, despite them being interlinked.

The guidelines issued by CWC for hazard classification don’t seem to have taken cognisance of this concept. However, dam break analysis is supposed to be done every five years. This analysis gives a fair idea of damage that would be sustained in case the dam breaks. If it is done credibly and regularly, it can help identify cases of hazard creep and help take appropriate action on this. However, there is no evidence of credible, regular updating of Dam Break Analysis, downstream river carrying capacity, inundation maps, early warning systems or disaster management plan. All of this also needs to be promptly in the public domain for each dam, which is not the case today for any dam.

Dam Safety Act 2021

India has a federal Dam Safety Act 2021 (DSA) to provide for dam safety all across the country. DSA has created a regulatory and institutional framework at both the central and at state level. It lays down mandatory processes and procedures to be followed by the dam owners, state dam safety organisations (SDSOs) and national dam safety authority (NDSA). Apart from standards and guidelines for regular maintenance and operation to be formulated by NDSA with recommendations from National Committee on Dam Safety (NCDS), there are specific obligations cast upon dam owners and SDSOs to deal with times of emergency, natural disaster and extreme weather conditions. SDSO is responsible for safe operation of all dams within its jurisdiction except the ones owned by central public sector undertakings or where a dam is an inter-state project. In such cases, the functions of SDSO shall be discharged by the NDSA.

NCDS, the supreme body in the hierarchy of dam safety institutional framework, has been entrusted with specific functions enumerated in the schedule appended with the Act. This includes evolving dam safety policies and recommending necessary regulations as may be required. It is required to meet twice a year (once before the monsoons) and can call in its meeting dam owners and experts as deemed appropriate for effective discharge of its functions.

NDSA is the operational arm of the institutional framework of dam safety at the national level and provides secretarial assistance to the NCDS and its sub-committees. NDSA is responsible for implementation of the policies made by NCDS. It formulates regulations on various aspects of dam safety based on the NCDS’ recommendations. NDSA adjudicates disputes between dam owners and SDSO or SDSOs of different states. NDSA has four regional offices.

The state committee on dam safety (SCDS) has been entrusted with specific functions to prevent dam failure-related disasters under this Act as per guidelines, standards and other directions on dam safety issued by the NDSA. SCDS oversees the SDSOs. The state committee is responsible for assessing potential implication of reservoir filling of a specified dam in the state on any upstream state, and also required to coordinate mitigation measures with such upstream states. It is the responsibility of the state committee to assess potential implication of failure of a specified dam in the state on any downstream state, and coordinate mitigation measures with such downstream states. DSA mandates vulnerability and hazard classification of all specified dams by SDSO and laying down of uniform criteria in this regard is to be done by NDSA.

While there is no question that India, the third-largest owner of large dams in the world, urgently needs a transparent, accountable and participatory dam safety mechanism, the institutional set up formed under DSA leaves a lot to be desired. First, the institutions formed do not have any place for independent members. Second, the CWC, the focal point of the institutions, has a very poor track record. Third, the Act does not provide that all information related to the dam safety must be put promptly in the public domain, including reports, minutes and agendas of all committees and authorities formed under the DSA. Lack of transparency seems to be the norm here. The DSA is basically focussed on the structural safety of dams, and has very little provision for operational safety of the dam. The track record of the functioning of the DSA so far — although it has only been two years — does not inspire much confidence, when we see the experience with recent dam failures, both in terms of structural failures and operational failures.

Specified Dams in Himachal Pradesh and HP-SDSO

In Himachal Pradesh (HP), there are 23 specified dams. Therefore, the SDSO can be headed by an officer of the level of superintending engineer who reports to the technical head of the department of dam safety in the state. Of these 23 specified dams, 4 are owned by the state, 9 by private companies and 10 by central public undertakings for which NDSA is supposed to act as DSO. The Directorate of Energy is the SDSO for large dams in the state and is also responsible for monitoring Safety and Quality control of all the hydroelectric projects (HEPs) commissioned or under execution. Surveillance and inspection is the duty of the state dam safety organisation which, in turn, reports to the SCDS. SDSO is required to keep perpetual surveillance, carry out inspections; and monitor the operation and maintenance of each specified dam under their jurisdiction. Each dam under their jurisdiction is mandated to be classified as per such vulnerability and hazard classification criteria as may be specified by the regulations. SDSO is mandated to maintain a logbook regarding all dams containing all data related to dam inspection, surveillance and any other matter related to dam safety. This is required to be maintained as per regulation. SDSO is to prepare an annual report of safety status of each specified dam within three months of the end of the preceding financial year. This has to be presented to the national authority and the state government, which shall present it to the state legislature.

The national authority shall consolidate a national dam safety report and present it to the Centre within six months of the expiry of the preceding financial year. The central governemnt, in turn, will lay it before each House of Parliament. This report is also given to NDMA and has to be made available in the public domain. No such reports are known to be available at state or central level so far.

Obligations of Dam Owners as per DSA

There are several specific obligations that have been cast upon dam owners under DSA. There is a chapter in DSA which deals with emergency action plans (EAP) and disaster management. Emergency management, which is the objective of EAP, is generally understood to mean the capacity to respond to emergencies and to mitigate their consequences. It includes anticipating the flood inflow and outflows, identifying the area that would be affected by the same, alerting such areas and having a plan to ensure timely and orderly evacuation of all such areas.

With regard to dam safety, emergency management also includes the ability to carry out actions to prevent a situation from developing into a dam failure. The emergency response aims to establish and maintain the ability to:

  • Prevent the development of harmful situations.
  • Issue alarms and warnings.
  • Limit damage.
  • Limit adverse consequences in general.

Owners of the specified dams, which are regulated by DSA in India, are under legal obligation to maintain certain specified scientific systems which enable them to anticipate and forecast inflow and outflow of water, forecast floods and issue early warning to people living downstream and upstream. All such information is required to be shared not only with public authorities in the district they are located in but also need to be actively and timely disseminated to pubic in general who are likely to get affected in case of a flood. The owners of specified dams are also mandated to compile all technical documentations concerning hydrology, dam foundation, structural engineering of dam, watershed upstream of dam, and nature or use of land downstream of dam along with information on all resources or facilities of economic, logistic or environmental importance which are likely to be affected due to dam failure. How often this information is required to be updated is not known. There would be significant variations in HP in resources or facilities of economic, logistic or environmental importance over the years given the almost unregulated development that that we are witness to in downstream areas.

Dam Safety Scenario in HP

In HP, 21 of 23 HEPs have been found to be guilty of non-compliance with dam safety norms by the state government during the July-Aug 2023 floods. Only the 800 megawatt (MW) Kol dam in Bilaspur and 1045 MW Karcham Wangtoo project in Kinnaur followed dam safety norms and the guidelines of the NDMA and CWC.

The safety norms were either neglected or were not followed as per standard DSA guidelines, according to the statement of the Chief Secretary (CS) of the state. A part of the devastation could be attributed to dam authorities who did not comply with DSA and NDMA’s Oct 2015 guidelines for water release from the dam and lack of early warning systems. The CS has asked officials to see if relevant provisions under DSA like setting up of early warning system, water release guidelines, setting up of control rooms, reservoir maintenance, emergency action plan and better communication between dam sites and power houses, etc. are being implemented on the ground.

The definition of offence under DSA is, either obstruction of any official or employee or person authorised by Central Government or the State Government, or a person authorised by the National Committee or the Authority or the State Committee or the State Dam Safety Organisation in the discharge of his functions or refusal to comply with any directions of any of these. Such offences are punishable with imprisonment for a term which may extend to one year or with fine, or with both and if the same results in loss of lives or imminent danger thereof, shall be punishable with imprisonment for a term which may extend to two years. The orders though have to be complied with by dam owners in letter and spirit.

DSA also envisages a situation where an offence is committed by a government department or is committed in connivance or with the consent of or can be attributed to the neglect of the government department. In such cases, either the head of the department or a person specifically held responsible for the same can be punished. If SDSO itself is found lacking, will anyone take action against them and fix accountability? No court can take cognizance of any offence punishable under this Act, except on a complaint made by the central government or the state government or a person authorised by the National Committee or the Authority or the State Committee or the State Dam Safety Organisation, as the case may be. Thus, to fix responsibility of the system is very tough but dam owners can surely be taken to task. However, this has not happened so far and how the state government deals with the violations by the 21 dam operators in HP during the 2023 southwest monsoon remains to be seen.

It is a matter of investigation as to what exactly transpired in HP which exacerbated the unprecedent floods and consequent devastation apart from extremely heavy rains. Did dam operators follow safey guidelines and norms to do everything possible to minimise downstream flood impacts? Was there anything that dam authorities could have done which would have helped to mitigate the impact of the floods? How much time did they have to react? Could they have better regulated the quantum as well as timing of water discharge?

Let’s have a look at the Beas river in HP, which consists of four sub-valleys (Kullu, Parbati, Garsa and Sainj), and the dams on which were in the eye of the storm (Malana 2, Larji and Pandoh, Parbati III and Pong). In addition to these Beas basin dams, Bhakra and other dams in the Sutlej basin were also alleged to have contributed to the flood disaster. All these dams are supposed to have a hazard classification of III as per informal official resources. 

DamCapacityType Live Reservoir capacity/ gross storage capacityCatchment areaFlood designOwned by
45 m high Malana 2 dam on malana Khad100MWRun of the river2.875 lakh cu m/ 3.79 lakh cu m177.75 sq km650 cumecGreenko
43 m high Parbati III dam on Sainj and outflows from Parbati-II520MWRun of the river12.825 lakh cu m/ 16.68 lakh cu m650 sq km3300 cumecsNHPC
26.5 m high Larji dam on Beas126MWRun of the river23 lakh cu m/ 34.3 lakh cu m4921 sq km8100 cumecsHPSEB
76 m high Pandoh dam on Beas990MWMultipurpose324.4 lakh cu m /410 lakh cu m5278 sq km9,939 cumecsBBMB
Pong Beas396 MWMultipurpose7.3 billion cu m /8.57 billion cu m12,560 Sq. Kms12375 cumecsBBMB

These dams had to release water at some stage when they were full. But, they were supposed to follow norms to ensure that the flood damage downstream was minismised and vulnerable areas alerted. At the peak of the recent floods, Larji dam got about 5,700 cubic metres of water per second. Its design flood has the capacity to discharge 8,100 cubic metre per second meaning the dam has been designed to withstand floods where discharge could be up to 8,100 cubic metre per second.

As per dam experts, three of 23 specified dams in HP — Bhakra, Pong and Kol — have significantly large water reservoirs and can cause significant flooding, though others too are big and have reservoirs with several lakh cubic metres capacity. Each of these 23 dams therefore have capacity to add to a downstream flood disaster when not operated properly.

Malana II

What happened in Kullu district’s Malana was, however, a dam failure as per the definition in DSA when the gates of the dam got jammed and the impounded water started to flow from the top of the dam and also eroded the river banks on the sides.

“dam failure” means any failure of the structure or operation of a dam which leads to uncontrolled flow of impounded water resulting in downstream flooding, affecting the life and property of the people and the environment including flora, fauna and riverine ecology.

Explanation — For the purposes of this clause, failure in the operation shall mean such faulty operations of the dam which are inconsistent with the operation and maintenance manual.

If the operation, maintenance and monitoring of the dam was happening as per the requirement of the DSA, this situation could have been avoided. The overflowing of water due to jammed gates created an emergency situation as it could have damaged the structure at Malana 2 which, in turn, could have damaged the downstream project at Malana 1.

If the dam authorities had issued timely early warnings about the impending floods in view of extremely heavy, unprecedented rains in its catchment areas, could the magnitude of the disaster in the downstream areas have been reduced?

Under DSA, EAPs are required to be made after a consultation process with various state departments responsible for disaster management and relief as well as the state disaster management authority in order to have coordination and transparency among them all. Owners of other dams in the immediate vicinity , that are likely to be affected, are also required to be consulted while making an EAP. If such a collaborative effort is required to be made for putting EAPs in place, why they don’t deliver at the time of emergency is something that we need to ponder over.

In DSA, main focus of the provisions regarding emergency action plan which are to be made by the dam owners of specified dams is the eventuality of dam failure. Though the consequences of dam failure and dam induced floods in terms of loss of life and property and its management is a part of EAP, the mandate regarding its management needs to be more robust. The emergency action plan as per DSA is required to be put into action as and when conditions arise which are hazardous or likely to be hazardous to a specified dam or potentially hazardous to public safety, infrastructure, other property or to the environment. In HP a flood situation hazardous to public safety, infrastructure and other property had arisen. Whether any of these erring dams’ EAPs have adequate provisions for mitigating loss to life and property in the downstream areas is something that everyone responsible for helping putting these EAPs in place should be held responsible for. In fact all the EAPs must be in public domain and should be shared in manner that local vulnerable communities can understand.

Another question that begs answer is about the accountability of dam authorities if the development in downstream areas is on flood plains of the river? Should dam owners be held responsible for contributory negligence about not raising an alarm about unregulated, indiscriminate development in their downstream areas? Should the dam operators not be warned about the changing carrying capacity of the river downstream from the dam due to enroachments on floodplains or reduced carrying capacity due to other reasons like dumping of solid wastes?

Sine qua non for effective flood control

Two important aspects that are infact sine qua non and can significantly strengthen our response to any emergency of the type that was witnessed in HP are: flood plain zoning of the rivers and effective and efficient catchment area treatment (CAT) plans. All dams have CAT plans made for their catchment area as a part of their EIA. But how effectively they deal with issues is a matter of investigation. To what extent and how well are the CAT plans implemented? How adequate are they? These are some relevant questions that both developers and regulators need to answer.

Sedimentation load in the river and in the reservoirs is an indication of the health of catchment area. In HP it was witnessed that the carrying capacity of the river has also been adversely impacted by indiscriminate dumping in the river and more discharge in the river is often associated with higher sedimentation.

As per Black’s Law dictionary (6th Edn., p.641) floodplain is the land adjacent to rivers, which, because of its level topography, floods when a river overflows. Flood Plain Zoning has been recognised as an effective non-structural measure for flood management. Flood plain zoning measures aim at demarcating zones or areas likely to be affected by floods of different magnitude or frequencies and probability levels, and specify the types of permissible developments in these zones. This is done with the aim that whenever floods actually occur, the damage can be minimised. Keeping in mind the increasing unpredictability of rainfall patterns and incidences of more frequent extreme rainfall, the definitions of the once-in-25-year-flood and once-in-100-year-flood need to be revised and changes in our floodplain zoning policies and practices implemented, though unfortunately we have no confidence inspiring policies or practices.

Floodplain zoning guidelines and laws

The CWC prepared flood plain zoning guidelines and the Model Bill for Floodplain Zoning in 1975. But it has done nothing to inspire confidence in ensuring the implementation of such policies. Four states enacted flood plain zoning acts: Manipur in 1978, Rajasthan in 1990, Jammu and Kashmir in 2005 and Uttarakhand in 2012. But none of the states have effectively implemented such Acts. These Acts provide for the establishment of a “Flood Zoning Authority” which is authorised to conduct surveys to determine the nature of extent of flood plains, prohibit or restrict the use of land in them, and impose penalties for non-compliance.

In Manipur, the state government notified the delimitation of flood zones and prohibition of construction activities on them in 1988. The Uttarakhand government started demarcating flood lines in 2020. However, neither Uttarakhand nor Manipur are known to have implemented the regulations effectively. Demarcation of flood lines and enforcement of flood plain zoning has not been done in the other two states where flood plain zoning laws have been passed, i.e. Rajasthan and Jammu and Kashmir (now a Union territory).

NGT order on floodplains

In HP, there is no law which mandates flood plain zoning except the decision of the National Green Tribunal (NGT) which has to be followed. NGT, vide its order/judgment dated 10.12.2015, in OA No 200 of 2014 – M.C. Mehta vs Union of India and ors. has inter-alia directed that as an interim measure, at least 100 m from middle of the river would be treated and dealt with as ‘Eco sensitive and prohibited zone’. No activity whether permanent or temporary in nature will be permitted to be carried on in this zone including camping. The area beyond 100 metres and less than 300 metres would be treated as regulatory zone in the hilly terrain, for which the State will comply with the above directions.

Further, vide its order dated 15.12.2017, the NGT has directed that no construction would be permitted in the Flood Plain in consonance with the judgement of the Tribunal in the case of Indian Council for Enviro-Legal Action Vs. National Ganga River Basin Authority & Ors. The NGT reiterated that in the area falling within 50 metres from edge of the river in the hilly terrain, no construction would be permitted, nor any other activity carried out and it shall be treated as Prohibitory Zone. Beyond 50 metres and up to 100 metres in the hilly terrain it shall be treated as Regulatory Zone. Regulatory activity shall be notified by the State and till that time there shall be no construction activity permitted in that area. Once the river enters the plain or even hilly areas where width of the river is more than 70 metres, in that event area of 100 metres from the edge of the river shall be treated as Prohibitory Zone while 100 metres to 300 metres would be treated as Regulatory Zone and till the time the State notifies the restricted activities, there shall be no construction activity even in the Regulatory Zone.

We need a holistic view and a comprehensive strategy in place if we want to reduce the impact of such incidents as were witnessed in 2023 in HP in future. The notices given to 21 dam operators should be put in public domain and taken to their logical conclusion, fixing accountability. Since the 21 operators include those from the central, state and private sectors, all sectors can be put on notice to improve their operations. Where there are lapses in state government functioning, including monitoring and compliance, that should also be addressed. The National Highways Authority of India, which has been also put on notice for encroaching on the Beas riverbed, also needs to be held accountable for the muck dumping in rivers, as determined by the High Court. The state dam safety institutions need to become much more transparent and they can, in fact, show the path for the rest of the country. On flood plain zoning policies and practices, HP can start with rigorously implementing the NGT orders and also bringing its own policy and regulations.

All this becomes even more imperative and urgent considering the changing climate. The rainfall this year in HP is a rude reminder of that.

Dam authorities have to be more transparent and vigilant themselves and about dam owners discharging their responsibility regrading dam safety with utmost care. The system needs to be cognisant of hazard creep and keep it in check. Flood plain zoning of rivers is something that needs to be done on war footing to minimise flood disasters around our future development and also to reduce the hazard creep.

Archana Vaidya is a Natural Resource Management & Environment Law Consultant. Himanshu Thakkar is Coordinator of South Asia Network on Dams, Rivers & People.

The article originally appeared on Down to Earth and was authored/co-authored by one of FELPRs team member.