DAMS  What is DAM ? – The arrangement made for systematic control of water flow for better optimum utilization of available water. – Humanity control over Natural resources

 8000 years ago - Sumerians build irrigation based civilization (between Tigris and Euphrates rivers)  1 ST CENTURY BC – Low height dams were built in Mediterranean middle east, central America, china  5 th century AD – Srilankan dam 34 mt height was built (worlds highest during that time)  1832 – Development of turbine lead to hydropower, large dams  century – Hydro electric plants started operations in US, ITALY, NORWAY DAMS-CIVILIZATION (HISTORY)

 1930-Improvement in turbine technology started mega DAM boom  Century – Started dams to meet water demands  Construction of large dams became usual with economic progress  1970 – It reached peak (i.e - each day 2-3 new dams commissioned in the world)  North America and Europe became technically attractive sites  45,000 – Large dams ( >15 mt height)  8,00,000 – Smaller Dams  2/3 rd of Large dams are in China  Asia, Europe, North America Constitutes for 95% of dams  Africa very little no of dams DAMS-CIVILIZATION (HISTORY)

Why DAMS (Reasons)  1.4 billion km3 of water is available in the world ( ice, water, water vapor)  97% of the above is sea water  Conversion of available water to usable water  Reducing variability in rivers flow w.r.t seasons  Water storage & availability due to climatic change  Regulating water for different purposes  Safety from social and economic tragedies  SUSTAINABLE ENERGY GENERATION

Purpose of Dams  48 % of Dams – for irrigation  contributes for large quantities of food production  15% of Dams – Domestic & Industrial water  8% of Dams – Flood control  4% of Dams – Recreation +Inland navigation fish farming  20 % of Dams – Generates hydropower  40% dams in Europe are hydropower dams  Most of the dams are multi purpose dams priorities may be different- includes IRRIGATION Flood control HYDROPOWER Domestic Industrial water supply

Purpose of Dams (India)  80% Rain happens during Monsoon ( 100 days span –45 rainy days)  60-80% Precipitation occurs in 6-8 intense rain spells  We can use – Insitu - Extending residence time (infiltration/ground water recharge) - Water shed MGMT - Little check dams - Small/ Medium irrigation works Still large water is getting wasted

Benefits of Dams  40 % Of world food production comes from Irrigated forming out of which 16% is contributed due to dams.  30-40% of 268 million hectares of irrigated land is watered from dams  19% of world energy comes from hydro- electric power ( which includes 150 countries) –90% of 24 countries –50% in 63 countries

Problems with Dams  Most of large dams – unable to achieve technical, economic,, social objectives, exhibited poor financial recovery costs.  Impact on Ecosystem are more ‘- than ‘+’ in many cases (wild life, species etc.)  Serious consequences on population displacement, cultures etc.  Loss of forests, wildlife habitat, the degradation of upstream catchments  Loss of aquatic biodiversity of up stream and down stream fisheries, services of flood plains, wetlands and adjacent marine system  Cumulative impacts on water quality, natural flooding and species composition where no of dams on same river  Sedimentation and long tem loss of storage is a serious concern globally  Water logging and salinity effects.

 The fragmentation and physical transformation of rivers.  Serious impacts on riverine ecosystems  Social consequences of large dams due to the displacement of people.  Water-logging and salinization of the surrounding lands.  Dislodging animal populations,damaging their habitat and cutting off their migratory routes  Disruption of fishing and waterway traffic  The emission of greenhouse gases from reservoirs due to rotting vegetation and carbon inflows from the catchment is a recently identified impact. Problems with Dams

SOCIOECONOMIC IMPACTS OF DAMS  Poorly managed involuntary displacement and loss of livelihood  Many displaced were not recognized and compensated  Depriving of indigenous people  locally available resources not available  Chance of water borne diseases  Inadequate distribution of project benefits to affected communities

Displacement due to Dams  Displacement by definition means involuntary  Displacement is not a single event, but a series of happenings, affecting human lives in many ways (years to decades gap)  For eg: Sradar sarovar dam Govt. it self encourages deforestation  Among affected communities, gender gaps have widened and women have frequently borne disproportionate share of the social costs and were often discriminated against in the sharing benefits

Ethical dilemma with dams  Rights of a small no.of locally affected population vs flights of large no. of potential beneficiaries  Conservation of Natural resources in the context of satisfaction of essential human needs by exploiting natural resources  Increased production of wealth to support growing needs vs fair distribution of accumulated wealth  If we are going to have sustainable development, we can not leave the environment and impacts on the environment should be minimized  There are more good dams than bad ones

CASE STUDY  NARMADA RIVER Dam  Three George Dam, china  Turkish Dam Controversy

Controversy on hydropower  Dams also provide energy in the form of Hydroelectric power  Hydropower constitutes 13% in the US ( reduction in 200 million tons of CO2/Year)  99% in NORWAY,75% in New Zealand,70% in Latin America,World wide 19 gigawatts electricity.  Hydropower plants are unsustainable in countries where frequent droughts cripples  Historically, Planners of large dams have ignored additional cost factors human resettlement costs, environmental consequences,capital costs, social costs (cost effectiveness ?)  Silatation can reduce dam capacity, diminishing poer capacity, depletion in d/s farm lands

Possible solutions to Improve the Acceptability of Dam projects  Public acceptance – key decision  Avoid and minimize ecosystem impacts  Engage in participatory, development needs and options  Affected people livelihood be improved  Resolve past inequities and injustices  Conduct regular and periodic review  Recognition of rights and assessment of risks, increase stake holders  Corrupt practices should be avoided etc.