The Union Cabinet had recently approved the proposal for introduction of Dam Safety Bill, 2018 in the Parliament. The objective is to help all states and Union Territories adopt uniform dam safety procedures.
Types of dam in India
Earth dam: Earthen dam utilizes natural materials with a minimum of processing. In India most of the dams are earthen dam.
Gravity dam: A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by primarily utilizing the weight of the material. Gravity dams provide some advantages over embankment dams.
Composite dam: It is an earthen dam which are provided with a stone masonry or concrete overflow (spillway) section.
Dam Safety in India- Background
- Dam safety is responsibility of dam owners which are generally state governments, central and state power generating PSUs, municipalities and private companies.
- In 1979 central government has created Dam Safety Organization in Central Water Commission (CWC) for assisting states in evaluating safety-related hazards in existing structures
- Subsequently, 17 states having significant numbers of dams had established their own Dam Safety Organizations and had taken up measures for ensuring dam safety in their respective jurisdictions.
- In 1987 central government had constituted National Committee on Dam Safety (NCDS) to act as a forum for exchange of views on techniques adopted for remedial measures to relieve distress in old dams.
- From the 8th five-year plan safety of dam came under planned activity. As a result, Dam Safety Assurance & Rehabilitation Project (DSARP), assisted by the World Bank, was implemented
- In 2005, DSARP was rechristened as Dam Rehabilitation and Improvement Project (DRIP)
- In 2010, a dam safety bill was introduced but the bill lapsed with the dissolution of the 15th Lok Sabha.
Dam Rehabilitation and Improvement Project (DRIP)
- To improve the safety and operational performance of selected existing dams in the territory of the participating states
- Strengthen the dam safety institutional setup in participating States as well as at Central level.
- This project is run by the Ministry of Water Resources, River Development and Ganga Rejuvenation (MoWR,RD& GR)
- It is an externally-aided project. 80% of the total project is provided by the World Bank as loan/credit and remaining 20% is borne by the States / Central Government (for CWC). Govt. of India has not sought funding from any internal agency for this project.
- It aims to repair and rehabilitation of about 225 dam projects across the seven states of India, namely Jharkhand (DVC), Karnataka, Kerala, Madhya Pradesh, Odisha, Tamil Nadu, and Uttarakhand (UJVNL).
- Project Management of DRIP is led by the Dam Safety Rehabilitation Directorate of the Central Water Commission as CPMU
- Collaboration with Japan Water Agency to developthe O&M Manual for Seismic Events.
Dam Health and Rehabilitation Monitoring Application (DHARMA)
- It is a web based asset management software to support the effective collection and management of asset and health data for all large dams in India.
- The software is designed for users at Central, State and Dam level, with user permission rights governed by their respective licenses.
The need for Dam Safety bill
- Lack of legal and institutional architecture for dam safety has raised fears unsafe dams, and the possibility of consequent disasters and loss of life and property.
- The existing organizations like NSDS, Central dam safety organization (CDSO) and state dam safety organizations (SDSO) do not have any statutory powers and are only advisory in nature.
- There are 5,254 large dams in operation and another 447 under-construction. Further there are numerous small and medium dams. The structural and operational safety of these dams is crucial because about 75% of large dams are more than 25 years old and about 164 dams are more than 100 years old.
- India has had 36 dam failures in the past. Any accident can lead to huge losses of lives and property, and also impact power generation, irrigation and water supply and flood control.
- Many dams have varied structural deficiencies andshortcomings in operation and monitoring facilities
Dam Safety Bill, 2018
- Dam Safety Bill 2018 will empower the dam safety institutional set-ups in both the Centre and States
- It will help in standardizing and improving dam safety practices across the country.
- It will address all issues concerning dam safety including regular inspection of dams, Emergency Action Plan, comprehensive dam safety review, adequate repair and maintenance funds for dam safety, Instrumentation and Safety Manuals.
- The bill will constitute National Committee on Dam Safety (NCDS), National Dam Safety Authority (NDSA), and State Dam Safety Organization (SDSO) with well defied duties and functions.
- The Bill provides for comprehensive safety evaluation (CSE) by independent panel of expert. First CSE within 5 years, and thereafter at regular intervals specified by NCDS.
- Comprehensive Safety Evaluation would be compulsory in case of major modification to structure or design criteria; discovery of unusual condition at dam or reservoir rim; an extreme hydrological or seismic event.
- The Bill provides for punishment / penalty if the dam safety provisions are not followed
Dam Safety Bill and Disaster Management:
The Bill provides for an emergency action plan to combat any disaster arising out of dam failures. The key provisions related to disaster management are:
- Establish hydro-meteorological network and inflow forecasting system
- Establish an emergency flood warning system
- Test periodically for the aptness of above systems;
- Make available information on anticipated inflows, outflows, flood warnings & adverse impacts to authorities and public domain;
- Carry out risk assessment study at interval as specified. First such study within five years;
- Prepare emergency action plan within 5 years; and for new dams, before the initial filling.
- Emergency Action Plan to include type of emergencies likely to occur; likely flood in the event of dam failure, along with probable areas, population, structures and installations likely to be affected; Warning procedures, inundation maps and advance preparations for handling adverse situations to avoid loss of human life; cooperation with disaster management agencies.
- Help states and UTs in adopting uniform dam safety procedures
- Ensure safety of dams
- Safeguard benefits from dams
- Safeguard human life, livestock and property
- Availability of fund
- Prioritizing investment according to risk
- States have very limited technical capabilities for analyzing instrumentation data for investigation and detection of dam distress.
- Real time inflow forecasting systems are not in place even in important reservoirs.
- Siltation of reservoir is a serious issue, though in most cases the extent of siltation continues to remain unknown.Desiltation of reservoir is difficult in many a cases owing to environmental concerns related to sediment disposal
- Few states raised objections that the Bill does not recognize dams and reservoirs run by long-standing inter-state agreements.
- Bill gives overriding powers to the National Dam Safety Organization to inspect any dams, among others
Why Tamil Nadu oppose the bill
- The Tamil Nadu Legislative Assembly passed a resolution to oppose the Dam Safety Bill, 2018 proposed by the Central government.
- The resolution mentions that all the states must be consulted and a consensus must be reached on the contents of the bill before it is passed in the Parliament.
- The Tamil Nadu government had opposed it on the grounds that it overrode the federal nature of the constitution
- Bill give overriding power to NDSA over state committee on dam safety in case of Dams constructed by the State Government in the neighbouring State over
- The state had objection to its coverage of Mullaperiyar dam.
|Mullaperiyar Dam Issue|
Tamil Nadu and Kerala have been in conflict over the Mullaperiyar dam in Kerala. The dam is owned by Tamil Nadu but situated in Kerala. When Tamil Nadu wanted to increase storage of the dam, Kerala opposed it citing safety threats. Eventually, a Supreme Court team inspected the dam and confirmed in November 2014 that the dam was safe.
In May 2014, the SC had struck down a Kerala Irrigation and Water Conservation (Amendment) Act 2006 limiting the full reservoir level to 136 feet. The dispute was over the Tamil Nadu government’s demand to raise the water level to 142 feet and carry out repair. Though the SC order went against Kerala, the Dam Safety Bill, 2018 has made Tamil Nadu concerned about its dams in other states
International Best Practice
Brazilian policy-makers and owners of large dams have been proactively working to improve the safety of dams. Several owners of hydropower dams, have self-enforced the 1987 ELETROBRAS guidelines. The Brazilian Dam Committee, founded in 1979, has worked to promote dam safety through a series of conferences, courses and publications. In 2010, the “Dam Safety Law” was ratified, which instituted the National Dam Safety Policy (PNSB. The policy enforces safety standards to reduce the number of accidents relating to dam failures. The law imposed a new set of responsibilities on dam owners and established new mandates for regulatory entities based on the type of dam, origins of the water rights, or licensing for construction.
Steps to be taken:
- Concerns of various states should be addressed before formalizing the law
- Training of dam engineers for inspection & monitoring,operation & maintenance, construction supervision, and emergency action planning & latest know-how, both in India and abroad, can ensure competence building in dam safety.
- A mechanism should be developed for availability and access to accurate and consistent data
- Dam safety should be integrated with land use planning (agriculture practices, settlements and industrial activities should be away from down streams) and geo-physical phenomena.