The Dam Safety Bill, 2019, which provides for the surveillance, inspection, operation and maintenance of all specified dams across the country, and has been debated for decades, finally got the nod of the Rajya Sabha.
- In August 2019, the Bill was approved by the Lok Sabha.
- The Government of India wanted a legislative framework regulating dam safety.
- It constituted a Committee in 1982 to review the existing practices and to evolve unified procedure for safety of dams in India.
- The Committee in its report in 1986 recommended a unified dam safety procedure for all dams underlining the necessity legislation on dam safety.
- Bihar enacted the Dam Safety Act, 2006.
- Kerala amended its Irrigation Act incorporating a dam safety provision. However, some States favoured Central uniform dam safety legislation.
- The undivided State of Andhra Pradesh and West Bengal adopted resolutions in their assemblies for an Act of Parliament.
- Accordingly, the Dam Safety Bill, 2010 was introduced in Lok Sabha in 2010. The Bill was referred to the parliamentary Standing Committee on Water Resources for examination and report.
- The Committee submitted its Report on the Dam Safety Bill, 2010, recommending wholesale amendments to the Bill.
- The Ministry of Water Resources, rechristened Water Power, withdrew the Bill and introduced a new Dam Safety Bill during the 16th Lok Sabha. But with the dissolution of the 16th Lok Sabha, the Dam Safety Bill, 2018 lapsed.
The Government introduced the Dam Safety Bill, 2019 in the very first session of the 17th Lok Sabha which has since been passed by the Rajya Sabha also.
Need of the Bill
- Dam failure: Globally, about 2.2% of dams build before 1950 have failed mainly due to flooding, inadequate spillway capacity, bad workmanship etc. Although India ranks third globally with above 5000 large dams in operation and about 500 under construction, India too has had its share of dam failures.
- There have been more than 36 reported failures cases so far. The major failure are as given below:
- The first failure was recorded in Madhya Pradesh in 1917 when the Tigra Dam failed due to overtopping.
- The worst dam disaster is, however, associated with the failure of Machu dam (Gujarat) in 1979 in which more than 2000 people died.
- Recently, the breach in Tiware dam in Maharashtra’s Konkan region swept away more than 20 people.
Key-highlights of the Bill
- Coverage: The Bill covers those dams having the height of over 15 metres and between 10 and 15 metres with certain stipulations.
- It seeks to create two national institutions:
National Committee on Dam Safety:
- The National Committee on Dam Safety will be constituted and will be chaired by the Chairperson, Central Water Commission. All other members will be nominated by the central government.
- Formulating policies and regulations regarding dam safety standards and prevention of dam failures.
- Analyzing causes of major dam failures and suggesting changes in dam safety practices.
National Dam Safety Authority:
- The National Dam Safety Authority will be headed by an officer, not below the rank of an Additional Secretary, who will be appointed by the central government.
- Implementing the policies formulated by the National Committee on Dam Safety.
- Resolving issues between State Dam Safety Organizations (SDSOs), or between a SDSO and any dam owner in that state.
- Specifying regulations for inspection and investigation of dams.
- Providing accreditation to agencies working on construction, design, and alteration of dams.
- The legislation also envisages the formation of State Dam Safety Organizations and State Committees on Dam Safety.
- Dam owners will be held responsible for construction, operation, maintenance and supervision of dams.
What are dams?
- Dam is defined as a barrier built across a stream, river or estuary to confine and check the flow of water for uses such as human consumption, irrigation, flood control and electric power generation.
- Lately, dams are considered more as hydropower generators while mitigation of flood, facilitation of irrigation and supply of drinking water, are considered only as additional benefits.
- A dam could be a central structure in a multipurpose scheme designed to conserve water resources on a regional basis.
- Multipurpose dams hold a special importance in developing countries, where a single dam might bring significant benefits related to hydroelectric power production, agricultural development, and industrial growth.
- However, dams have become a focus of environmental concern because of their impact on migrating fish and riparian ecosystems.
- In addition, large reservoirs could inundate vast tracts of land that are home to many people, and this has fostered opposition to dam projects by groups who question whether the benefits of proposed projects are worth the costs.
- Worldwide, the huge volume of water stored behind large dams is estimated at 7,000 to 8,300 cubic kilometres, enough to cover about 80 per cent of Canada's landmass under a metre of water.
What are the different Kinds of Dams?
- Diversion Dam - Like the name suggests, a diversion dam is used to divert water. They provide pressure to push water into ditches, canals, or other areas used for conveyance. Diversion dams are typically lower in height and have a small water storage area in its upstream.
- Buttress Dam - Buttress dams could take many forms, but they all consist of a sloping deck supported by intervals of buttresses. Buttress dams usually use less concrete than other dams but are not necessarily cheaper. There are three main buttress dams:
- multiple arch type
- massive head type
- deck type
- Embankment Dam - An embankment dam is a large, artificial dam that is constructed with natural excavated materials or industrial waste materials, such as compacted plastics, and various compositions of soil, sand, rock, and clay.
- Cofferdam - A cofferdam is a temporary, portable dam used for a variety of projects including bridge repair, shoreline restoration, pipeline installation, and many other construction projects.
- Storage Dam - These dams are not meant to divert or keep water out, but to keep water in. Storage dams are constructed to store water during the rainy seasons, supply water to the local wildlife, and store water for hydroelectric power generation, and irrigation. Storage dams are the most common types of dams.
- Detention Dam - Detention dams are specifically constructed for flood control by retarding flow downstream, helping reduce flash floods (to some extent).
- Gravity Dam - A gravity dam is a massive, man-made concrete dam designed to hold large volumes of water.
Dam Safety in India
The current situation
- More than 75% of the country’s dams are over 25 years old and about 164 dams are more than 100 years old.
- Over 1,115 large dams that will be roughly 50 years old in 2025
- more than 4,250 large dams in the country will be over 50 years old in 2050
- 64 large dams will be more than 150 years old in 2050
- These pose growing threat.
- For example: Approximately 3.5 million people are at risk if India’s Mullaperiyar dam in Kerala, built over 100 years ago, “were to fail”. The dam, in a seismically active area, shows significant structural flaws and its management is a contentious issue between Kerala and Tamil Nadu States.
- Many dams have varied structural deficiencies and shortcomings in operation and monitoring facilities, while few do not meet the present design standard- both structurally as well as hydrologically.
- With the increasing number of dams becoming older and older, dam failures are more expected now.
- Additionally, most of the States have been failing to provide sufficient budgets for maintenance and repair of the dam.
- Many States also lack the institutional and technical capacities for addressing dam safety issues.
Dam Safety Framework in India
National Committee on Dam Safety (NCDS) –
- Establishment: It was constituted by Government of India in 1987.
- Chaired by: It is chaired by Chairman, Central Water Commission and is represented by all the States having significant number of large dams and other dam owning organizations.
- Objective: NCDS suggests ways to bring dam safety activities in line with the latest state of the art consistent with the Indian conditions and acts as a forum for exchange of views on techniques adopted for remedial measures to relieve distress in old dams.
Central Dam Safety Organization (CDSO) –
- Establishment: It was established under Central Water Commission in 1979.
- Objective: The objectives of Central Dam Safety Organization are:
- Assist in identifying the causes of potential distress
- Perform a coordinative and advisory role for the State Governments
- Lay down guidelines, compile technical literature, organize trainings, etc.
- create awareness in the states about dam safety
State Dam Safety Organizations (SDSO)-
- They are Dam Safety Organization/Cell established in eighteen States and four dam owning organizations (NHPC, BBMB, DVC and Kerala State Electricity Board).
Important Government Initiatives for Dam Safety
- Dam Rehabilitation and Improvement Project (DRIP)
- Dam Health And Rehabilitation Monitoring Application (DHARMA)
- Seismic Hazard Mapping along with development of Seismic Hazard Assessment Information System (SHAISYS)
- Other Initiatives include Design Flood Review, publication of important Guidelines as well as Manuals dealing with Dam Safety Management, preparation of operation and maintenance Manuals, Emergency Action Plans, etc.
Dams are a critical infrastructure constructed with large investment for multi-purpose uses such as irrigation, power generation, flood moderation and supply of water for drinking and industrial purposes. An unsafe dam constitutes a hazard to human life, ecology and public and private assets including crops, houses, buildings, canals and roads. Therefore, the safety of dam is a matter of great concern to the general public and becomes a national responsibility to take necessary steps to ensure their safety.
In this regard, the Bill will provide a robust legal and institutional framework for ensuring the safety of dam.