OCTOBER 1, 2018 LARGE DAMS PANEL PRESENTATION TEAM A GEOGRAPHY 412 - PDF document

OCTOBER 1, 2018 LARGE DAMS PANEL PRESENTATION TEAM A GEOGRAPHY 412

INTRODUCTION TO LARGE DAMS ANISHA NAVARATNAM Lar arge Dam Clas assifi fication ion: “A large dam is a dam with a height of 15 m or more from the foundation. If dams are between 5-15 m high and have a reservoir volume of 3 million cubic meters, they are al so classified as large dams” • 57,000 large dams worldwide in 2017 (ICOLD, 2017) • Mega-dam: crest height over 150 meters from its foundation Typ ypes of f Lar arge Dams: Reservoir Type Storage Projects, , Run-of-River Dams (limited daily pondage) Glob obal l Dis istr trib ibution on of f Dams: • Top three producers with 92% of the world’s largest dams: China, India, USA • Many dams were constructed between 1950-1970 during which period there was an increase in dam technology Source: International Commission on Large Dams. 2017 World Wor ld Com ommis ission on of f Dams: • Established between 1997 – 2001 to review and form international dam construction governance and standard (IRO, 2017) • Tri-sectoral network formed by representatives from governments, civil societies and businesses (IRO, 2017) • Objectives: o To review the effectiveness of large dams and assess alternatives for water resources and energy development o To develop international guidelines and standards for the planning, design, appraisal, construction, operation, monitoring and decommissioning of dams. 1

DAM EVOLUTION SPENCER CAIN • Dams are not geographically specific and can service societal needs in many ways including: (1) access to safe and clean drinking water; (2) reliable water source for agriculture; (3) flood control/management; (4) renewable energy source • Dam evolution has been focused on increasing performance and efficiency. Two performance indicators include schedule and budget (UNEP, 2000) Water Security: “the reliable availability of an acceptable quantity and quality of wate r for health, livelihoods and production” (Grey et al. 2007). Food System: A food system involves all processes and infrastructure in feeding a population. (Ericksen, 2007) Irrig igation ion Dams: water supply in regional irrigation systems • Performance Indicators: (1) physical performance on water delivery, area irrigated and cropping intensity; (2) cropping patterns and yields, as well as the value of production; (3) net financial and economic benefits. • Disadvantages: (1) often fail to recover the costs of construction and are less profitable overall; (2) secondary benefits, such as water access, are rarely used as specific targets. Hyd ydroele lectr tric ic Dam ams: deliver electric power have on average met expectations for the delivery of power • Hydropower dam evolution has focused on modifications to intake and outtake outlets to maximize electricity generated. • Disadvantages: (1) on average, almost half of the sample exceeded the set targets for power generation – with about 15% exceeding targets by a significant amount (UNEP, 2000); (2) higher-than-expected upstream irrigation abstractions and lower than-predicted natural stream flows can reduce power yielded ; (3) normal variations in weather and river flows dictate that virtually all-hydroelectric projects will have year-to-year fluctuations in output (UNEP, 2000) Water Su Supply y Dams: : focus on establishing a permanent source of water (reservoirs) to meet water demand • A reservoir is a contained or enlarged natural, artificial lake, storage pond or impoundment created using a dam or lock to store water. • Water supply dams are cheap because bounded by natural topography and located at the narrowest point downstream of the basin to reduce construction costs and for this points ’ increased erosion strength. • Disadvantages: (1) traditionally water supply dams have fallen short of intended timing and targets for bulk water delivery and have exhibited poor financial cost recovery and economic performance (UNEP, 2000); (2) at current rates, water fees are rarely sufficient to recover both capital and recurrent costs for water supply systems in many developing countries Fl Flood od Con ontr trol ol Dam ams: : used historically to manage water surges and mitigate flows from damaging settlements • Water is stored behind dam and released slowly over time • Flood control dam evolution has emphasized a growing concern over the cost and effectiveness of large dams and related structural measures as long-term responses to floods • Disadvantages: (1) loss of beneficial aspects of natural flooding (i.e. floodplain fertility); (2) dam failure results in extreme flooding; (3) downstream damage is extreme, often downstream communities must implement an increased protection levels which sometimes prove inadequate (UNEP, 2000) 2

DISPLACEMENT ANISHA NAVARATNAM Dam Induced Dis isplac acement: t: displacement of humans and animals caused by reservoir flooding and dam and infrastructure construction Social So al Dis isplac acement: t: • Estimated by 2000, 40 million people were displaced by large dams and their infrastructure • Often densely populated countries have the highest displacement rates as water is needed to meet populations ’ needs • Site C – Cache Creek / Bear Flats: BC Hydro evaluated two options; Peace Valley Landowner’s Association formed oppose Site C; families who had been living in the Pea ce Region since the early 1900’s who had been displaced by the Bennett Dam will be relocated again. Their lifestyles depend on the land. • Barra Grande Land, Brazil: site was favourable for steep slopes which were also favourable for agriculture; displacement of over 430 families; inadequately compensated as loss of land around dam site drove up regions’ agricultural prices (Rondinelli -Roquette, 2017) Envir viron onmental al Dis isplac acement: t: • Reservoir flooding results in destruction of terrestrial ecosystems • Dam wall may result in ecosystem fragmentation and block fish migrations from spawning habitat 3

SOCIAL IMPACTS AMBER POMEROY Environmental Justice: exposures to pollution and other environmental risks are unequally distributed by race and class (Mohai, 2009) Othering: Othering, is portraying the other essentially different, and translating this difference to inferiority (Krumer-Nevo and Sidi, 2012). Perspectiv ives: Political and economic goals are tied to social goals. Therefore, the interests of local communities, the global community and economic interests are intertwined. Arguments ts: Outl tlin ined in in th the Wor orld ld Commis ission on on on Dams (UNEP, 2000) Environmental Justice Case studies indicate that vulnerable groups and future generations are likely to bear a disproportionate share of the social and environmental costs of large dam projects without gaining a commensurate share of the economic benefits. Costs and Benefits There is a problem with simply weighing positives and negatives of dam construction. As broader costs and benefits including economic, environmental and social considerations fall unequally within society. Alternatives Due to reasons including the lack of equity in the distribution of benefits, alternatives are considered to meet water and energy development needs. Alternatives such as reducing consumption are being considered viable options. Main ain So Social al Terms: Resettlement Issues “Cash compensation is a principal vehicle for delivering resettlement benefits, but it has often been delayed and, even when paid on time, has usually failed to replace lost livelihoods” (UNEP, 2000). Initial Plans “Dams are often discussed years before project development it seriously considered and once a site is identified a form of ‘planning blight’ can take place, making g overnments, businesses, farmers and others reluctant to undertake further productive investments in areas that subsequently might be flooded. Communities can live for decades starved of development and welfare investments” (UNEP, 2000) Jobs/Boom Dams construction can have economic benefits such as increasing tourism or ship navigation (My Yangtze Cruise, 2010). There can also be an increase in jobs. However, while “new jobs are created both for skilled and unskilled workers during the construction phase…th e beneficial effect on local communities is often transient due to the short- lived, pulse impact of the construction economy and dam construction sites” (UNEP, 2000). This can also cause psychological stress and health problems on the local community. Cultural/Traditional Loss Dam construction can result in “the loss of access to traditional means of livelihood, such as agricultural production and fishing practices (UNEP, 2000) 4