Dam Management in India
27th Aug, 2022
Recently, the outer part of the “Karam Dam”, which is being built on the Karam River, a tributary of the Narmada, collapsed.
- With the increasing events of Dam failures in India, questions the policy regarding Dam management and its accountability.
- A dam is defined as a barrier built across a stream, river or estuary to confine and check the flow of water for such uses as human consumption, irrigation, flood control and electric-power generation.
- Lately, dams are seen more as hydropower generators with flood mitigation, irrigation and drinking water supply only being added benefits.
- However, globally about 2.2% of dams built before 1950 have failed mainly due to flooding, inadequate spillway capacity, bad workmanship etc.
- India ranks third globally with 5264 large dams in operation and about 437 are under construction. But India too has had its share of dam failures. There are more than 36 reported failure cases so far.
- The first failure was recorded in Madhya Pradesh in 1917 when the Tigra Dam failed due to overtopping.
Examples of floods in India exacerbated by dams:
- There are numerous instances of this kind, including the floods in Uttarakhand (June 2013), Tehri (September 2010), Hirakud (2009, 2011, 2014), Damodar dams (multiple years), Krishna basin dams (2006, October 2009), Ukai (August 2006), Chennai floods (December 2015), Bansagar dam (August 2016), Kurichu dam in Bhutan (2004, 2016, others), and Ranganadi (2017) and Doyang (2018), among other dams, where flawed operation of the dams created or worsened flood disasters in the downstream areas.
Need for Dam Safety in India
- Over 75% of the country’s dams are over 25 years old and about 164 dams are more than 100 years old.
- With the increasing number of dams becoming older and older, dam failures are more expected now.
- Ensuring Dam Safety is essential for safeguarding huge investments in infrastructure.
- It is also crucial for safeguarding human life, and the properties of the people living downstream of the dams.
What are the concerns associated with the present system of Dam Management?
- Varied structural deficiencies
- Shortcomings in operation and monitoring facilities,
- Structure does not meet the present design standard- both structurally and hydrologically
- 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.
- Lack of systematic assessment and monitoring
- Real-time inflow forecasting systems are not in place even in important reservoirs
- Dam design drawings or drawings as constructed are not available
- Dam Safety Organizations (DSO) in states are short of adequate manpower
- Dam Rehabilitation and Improvement Project (DRIP):Launched in 2012, with World Bank to improve safety and operational performance of selected dams, along with institutional strengthening with system wide management approach.
In 2018, the government approved the extension of the DRIP Project for two more years with the revised scheduled closure in June 2020. Presently 198 dam projects are being rehabilitated under the DRIP Project.
- Dam Health and Rehabilitation Monitoring Application (DHARMA): It is a web-based software package to support the effective collection and management of Dam Safety data in respect of all large dams in India.
- The software is designed for users at the Central, State and Dam level, with user permission rights governed by their respective licenses.
- Seismic Hazard Mapping along with the development of Seismic Hazard Assessment Information System (SHAISYS): It is also web-based interactive application tool being developed in CWC under Dam Safety Organisation (DSO) to estimate the seismic hazard at any point in the Indian region.
- The SHAISYS shall be capable of estimating seismic hazard using the deterministic as well as probabilistic approach.
- Other Initiatives– Other important activities include Design Flood Review, publication of important Guidelines as well as Manuals dealing with Dam Safety Management, preparation of O&M Manuals, and Emergency Action Plans.
Dam Safety Act, 2021
- Dam Safety Act 2021 aims at surveillance, inspection, operation and maintenance of all specified dams across the country.
- The Act applies to all specified dams in the country i.e., those dams having a height of over 15m and between 10m and 15m with certain design and structural conditions.
- Functions: Functions of the committee will include formulating policies and regulations regarding dam safety standards and prevention of dam failures, analysing the causes of major dam failures, and suggesting changes in dam safety practices.
It constitutes two National Bodies:
1. National Committee on Dam Safety: Its functions include evolving policies and recommending regulations regarding dam safety.
2. National Dam Safety Authority (NDSA): Its functions include implementing policies of the National Committee, and resolving matters between State Dam Safety Organisations (SDSOs), or between an SDSO and any dam owner in that state.
A risk-based approach is necessary for making sound decisions on dam safety. Dam failure analysis is fundamental to a risk-based approach to dam safety. Some of the technological and institutional foundations for building a robust risk-based decision-making system for this sector are already in place. A few changes in policy, and leveraging already built resources (E.g.: WRIS, and MoEF environmental clearance portal) can enable India to build a bear, safer dam sector.