Nine Months after the Launch of the World Commission on Dams Report

The World Commission on Dams (WCD) was established in 1998 in response to the increasing controversies over dam projects. Its report, published in November 2000, concluded that dams have delivered many benefits, but in too many cases the price paid to secure those benefits was unnecessarily high and adverse impacts could have been avoided. In recommending a way forward, the WCD presented a new framework for decision making based on a recognition of rights and an assessment of risks. The diverse reactions to the findings and recommendations of the report are outlined in the paper and some of the follow-up activities by government agencies, international organizations and the private sector described. The seven strategic priorities articulated in the WCD's report have received a considerable degree of support and provide a foundation for local processes to follow. A case is made for inclusive, multi-stakeholder processes at national and project level to find a way forward beyond conflicts.     

Aftermath,Overview and an Appraisal of Past Events Leading to Some of the Imbalances in the Report of the World Commission on Dams

As soon as the composition of the World Commission on Dams (WCD) was declared, it was not difficult for most of the developing countries to visualize the possible nature of the report it was to generate, despite all the talk about its so-called 'participatory' and 'transparent' consultation process. Even the gullible were disillusioned when the report was launched with a great fanfare. This article looks into the myth of WCD's claim of a so-called consensus report, of bringing proponents and opponents of dams together and the 'knowledge base' that was supposed to have been generated. It discusses the inherent weakness in the process of consultations of WCD and the genesis of imbalances in the report that are so obvious, thereby leaving no choice with the developing countries but to reject it.     

Effect of Proposed Large Dams on Water Flows and Hydropower Production in the Sekong,Sesan and Srepok Rivers of the Mekong Basin

Water flow patterns in the Mekong are changing because of on‐going rapid hydropower development triggered by economic growth. Of immediate concern are the current and proposed hydropower dams in the transboundary Srepok, Sesan and Srekong (3S) Rivers, which contribute up to 20% of the Mekong's annual flows, have a large potential for energy production and provide critical ecosystem services to the downstream Tonle Sap Lake and Mekong Delta. The objective of this paper is to determine how the operation of the proposed largest individual dams and cascade dam schemes in the 3S Rivers will affect flow regimes and energy production. Daily flows were simulated over 20 years using the Soil and Water Assessment Tool and HEC‐ResSim models for a range of dam development and operations scenarios. The development of all dams in the 3S basin under an operation scheme to maximize individual electricity production results in an average 98% increase in dry season flows at the 3S outlet. Over 55% of dry season flows changes are caused by seven proposed large dams, with the Lower Srepok 3 project causing the highest impact. The seven large dams will generate 33.0 GWh/day with a water volume of 17 679 x 10⁶ m³, compared with the current and definite future dams generating 73.2 GWh/day with a much lower volume of 6616 x 10⁶ m³. When a cascade of dams are operational, downstream dams with small reservoirs will produce more energy. However, the marginal increase in energy production from the development of additional dams in the 3S basin will decline rapidly relative to the required water storage increase,. Strategic decision‐making on the future of each large proposed dam in the 3S basin needs to be considered by local governments after understanding cumulative operation effects and with further consideration to the potential impact on downstream ecosystem productivity and livelihoods. Copyright © 2016 John Wiley & Sons, Ltd.     

河流水电梯级开发水温累积影响研究

从流域开发对河流水温结构的影响方面进行分析,采用现场观测和数学模型计算相结合的方法,对水库水温结构进行研究,同时,对梯级电站下泄水温的累积影响进行数值模拟研究。研究结果表明,高坝大库对河流水温改变大,对水温累积影响的贡献大;流域开发程度越高,累积影响越大,5个梯级比3个梯级累积影响大。这一定量研究成果体现了梯级电站的水温累积影响和群体效应,可推进梯级水电站对河流水温影响的研究进程,并为研究大型电站运行减缓下泄低温水的对策措施提供依据和参考。     

Determining the effects of dams on subdaily variation in river flows at a whole‐basin scale

River regulation can alter the frequency and magnitude of subdaily flow variations causing major impacts on ecological structure and function. We developed an approach to quantify subdaily flow variation for multiple sites across a large watershed to assess the potential impacts of different dam operations (flood control, run‐of‐river hydropower and peaking hydropower) on natural communities. We used hourly flow data over a 9‐year period from 30 stream gages throughout the Connecticut River basin to calculate four metrics of subdaily flow variation and to compare sites downstream of dams with unregulated sites. Our objectives were to (1) determine the temporal scale of data needed to characterize subdaily variability; (2) compare the frequency of days with high subdaily flow variation downstream of dams and unregulated sites; (3) analyse the magnitude of subdaily variation at all sites and (4) identify individual sites that had subdaily variation significantly higher than unregulated locations. We found that estimates of flow variability based on daily mean flow data were not sufficient to characterize subdaily flow patterns. Alteration of subdaily flows was evident in the number of days natural ranges of variability were exceeded, rather than in the magnitude of subdaily variation, suggesting that all rivers may exhibit highly variable subdaily flows, but altered rivers exhibit this variability more frequently. Peaking hydropower facilities had the most highly altered subdaily flows; however, we observed significantly altered ranges of subdaily variability downstream of some flood‐control and run‐of‐river hydropower dams. Our analysis can be used to identify situations where dam operating procedures could be modified to reduce the level of hydrologic alteration. Copyright © 2009 John Wiley & Sons, Ltd.     

流域化水电站大坝安全管理模式浅析

随着中国水电开发事业的不断推进,一系列世界级水电工程和高坝大库逐步在国内形成,水电站大坝安全管理风险和压力也上升到了新的高度。为适应新的形势,水电企业有必要不断提升水电站大坝安全管理水平,确保大坝的安全可靠运行。笔者对国内水电企业大坝安全管理模式进行了梳理和归纳,重点汇总了流域化大坝安全管理的多个案例,并开展了简要分析,认为流域化大坝安全管理集中了企业内部大坝管理专业力量,优化了大坝管理资源配置,提升了工作效率,对于负责流域梯级电站群运行的企业,可根据自身情况,博采众长,创建符合自身需求的流域化大坝安全管理模式。     

水电站大坝维修加固的实践与思考

我国水电站大坝维修加固已取得明显的工程效果和巨大的社会效益，并积累了丰富的经验，为了适应新世纪的要求，要进一步加深对大坝风险性的认识，持续开展维修加固工作，加大科技投入，集中力量攻克一些技术难关，深入研究大坝缺陷产生的原因，将预防措施与工程治理有机结合起来，多方面筹措资金，使杆些险，病坝早日脱险拉摘帽，确保大坝的安全运行，充分发挥水电站的综合效益.     

The World Commission on Dams and the Need for a New Development Paradigm

Responding to the unanimous recommendation of a multi-stakeholder workshop, the creation of the World Commission on Dams (WCD) was formally announced in February 1998. Financially supported by 53 public, private and civil society agencies, the twelve Commissioners released the WCD Final Report in London in November 2000. In this article a former Commissioner discusses the "WCD process" from its origin to the present. The contents of the final report are described, with special attention paid to the significance of the WCD's rights and risks approach as a first step toward a new development paradigm for an increasingly global, 21st century society.     

Re‐establishment of fish passage for conserving threatened migratory species of West‐Indian Himalayas

Fish passes are structures (natural or manmade) bypassing barriers (e.g., dams), enabling satisfactory movement of migratory fish species. Reestablishment of fish passage, including facilitating overcoming barriers presented by impoundments or restoration of defunct structures, is attracting interest among scientists and policymakers as a mechanism to enable recovery of target fish species or fish communities. However, it is also important to note that fish passes may also act as ecological traps in some large neotropical rivers. A diversity of multispecies fish passage designs have been implemented in North and South America, Europe, and Australia, with varying efficacy for different species. However, field surveys between 2010 and 2018 supported by a review of published literature (N = 217) using Google Scholar search engine using six key terms reveal that few fish passes have been constructed in dams in the Indian Himalayan region, and their efficacy is largely unproven. Major problems associated with fish pass designs include uneven success across a range of species and largely untested effectiveness at the large scale of many major dams. The objective of this paper is to stress upon the requirement of a new approach to understand the operational drawbacks of different types of fish pass and to take an adaptive approach to both design and operation using field data to improve fish pass efficiency. These measures could contribute significantly to the conservation of threatened migratory fish in the increasingly impounded rivers of the Indian Himalayan region.     

Development and Large Dams: A Global Perspective

Water-retaining structures have been built to facilitate human development for some 5000 years. This paper focuses specifically on their development during the past 50 years, and points out that analyses of actual impacts of large dams are few and far between. Consequently many myths have now enshrined themselves in the literature as facts. The background to the controversy over the Aswan High Dam is analysed. While the western world has basically constructed the dams necessary, the situation is very different from the perspectives of the developing countries, where progress has left much to be desired. Climatic, technical, economic, social, environmental and institutional conditions are very different between the developed and the developing countries, and hence the approaches to water management cannot be identical for the whole world. The main issue facing the developing countries is not whether large dams have an important role to play in the coming decades, since there is really no other choice, but rather how best we can continue to improve their overall effectiveness for human welfare, eradicate poverty and preserve the environment.     

The Role of Dams in Development

Growing population and rising levels of economic activities increase human demand for water and related services. In the past large dams have often been seen as an effective way of meeting water and energy needs. However, a global review recently carried out by the World Commission on Dams has emphasized the wide range of problems associated with dams, making it more difficult to finance large dams. This paper deals with the role of dams in development. The need for dams, the purpose of large-dam building, major benefits and social and environmental considerations are dealt with. As a case study, the contribution of dams to Turkey's economy is described.     

雅砻江流域水电开发中的关键技术问题及研究进展

雅砻江流域规划21座梯级水电站,总装机规模约3000万kW,在中国十三大水电基地中名列第三。在2020年前,雅砻江上将建成一系列世界级工程,包括世界最高混凝土双曲拱坝、300m高土石坝及世界最大规模水工隧洞群等。在雅砻江水电开发的过程中,将面临水力学、岩石力学、工程地质、高坝设计、建筑材料、流域梯级水电站建设运行管理等诸多世界水电科技前沿的技术难题。本文拟对雅砻江流域水电开发中的关键技术问题和主要研究进展进行分析,并对下一步研究对策提出建议。     

Management of Upstream Dams and Flood Protection of the Transboundary River Evros/Maritza

The flood frequency and the dikes overtopping at the downstream part of transboundary (Bulgaria–Greece–Turkey) river Evros/Maritza has increased dramatically in the last 13 years. It is not clear if the increase of flood frequency is due to climatic changes or to inappropriate management of Bulgarian dams. This fact raises the question of modeling the flood routing through the many dams in the Bulgarian territory (upstream), which receive the runoff of the 38% of the area of the Evros watershed in Bulgaria, in a way to protect the downstream countries from flooding. The basic objective of this paper is the development of a new management tool (software) for the simulation of the rainfall–runoff and routing process taking into account the existence of many dams and mainly their operation not only from a hydrologic viewpoint, but also from the administrative, with emphasis on the “energy–economic” exploitation of the reservoirs. The developed software (named Evrofloods) models the rainfall–runoff, the routing of runoff through the various Evros river tributaries taking in account various scenarios of the runoff through the artificial reservoirs with the aim of optimal management of the water released from the dams spillways and turbines. The “optimal management” is related with the finding for a given rainfall distribution, the appropriate combination of actions at many reservoirs (“reservoirs management”) in order to prevent or mitigate the floods downstream, aiming at the same time to minimize hydroelectric energy loss. Although Evrofloods software is basically dedicated to the large Evros basin, it can be easily used to determine the management of large transboundary rivers with many artificial reservoirs to avoid floods downstream. Recent European legislation on floods encourages the good cooperation of neighbor countries, to avoid floods.     

Role of Large Dams in the Socio-economic Development of Mexico

In Mexico, 473 km 3 of water is renewed annually, of which 198.4 km 3 is abstracted by the productive sectors and for domestic purposes. Such figures, however, give a false sense of water abundance, because its spatial and temporal distribution is not homogeneous. In order to cope with this mismatch, numerous water-retaining structures have been constructed. Certainly, dams have been a key element to balance the spatial and the temporal variations in the water availability, and they have played a crucial role in the socio-economic development of Mexico. However, the benefits could be more if water management practices were more efficient, equitable and modern. This paper focuses specifically on dam development in Mexico, and it points out that, unquestionably, large dams have had direct, negative impacts. However, it should be noted that many of those negative impacts are the results of inefficient planning, inadequate expertise and improper management. Dams, like any other major infrastructures, have economic, environmental and social benefits and costs. Accordingly, the dams must be properly planned, built and managed with the best scientific and technical knowledge available. The real question for Mexico is not whether dams should be constructed or not, but rather how should the dams be planned and managed so that the economic, social and environmental benefits to the society as a whole can be maximized and the costs can be minimized.     

Understanding the Thermal Regime of Rivers Influenced by Small and Medium Size Dams in Eastern Canada

Although small and medium‐size dams are prevalent in North America, few studies have described their year‐round impacts on the thermal regime of rivers. The objective of this study was to quantify the impacts of two types of dams (run‐of‐river, storage with shallow reservoirs) on the thermal regime of rivers in eastern Canada. Thermal impacts of dams were assessed (i) for the open water period by evaluating their influence on the annual cycle in daily mean water temperature and residual variability and (ii) for the ice‐covered winter period by evaluating their influence on water temperature duration curves. Overall, results showed that the run‐of‐river dam (with limited storage capacity) did not have a significant effect on the thermal regime of the regulated river. At the two rivers regulated by storage dams with shallow reservoirs (mean depth < 6 m), the annual cycle in daily mean water temperature was significantly modified which led to warmer water temperatures in summer and autumn. From August to October, the monthly mean water temperature at rivers regulated by storage dams was 1.4 to 3.9°C warmer than at their respective reference sites. During the open water period, the two storage dams also reduced water temperature variability at a daily timescale while increased variability was observed in regulated rivers during the winter. Storage dams also had a warming effect during the winter and the winter median water temperature ranged between 1.0 and 2.1°C downstream of the two storage dams whereas water temperature remained stable and close to 0°C in unregulated rivers. The biological implications of the altered thermal regimes at rivers regulated by storage dams are discussed, in particular for salmonids. Copyright © 2016 John Wiley & Sons, Ltd.     

Determining Location and Capacity of Dams through Economic and Environmental Indicators

Construction of dams is a conventional way to deal with the problem of water scarcity in undeveloped basins. The economic and the environmental effects of dams are often evaluated locally rather than in a basin frame. The distinctive feature of this paper is to propose a basin-wide approach, comprised three steps for determining dams’ locations and dams’ capacities based on optimization modelling. Our approach provides an environmentally sound plan for surface water development that also results in the highest profit for the basin, for the sake of achieving sustainable development. The first step of our approach runs a mixed-integer linear model to give optimal locations and capacities of new dams for various number of dams along with satisfying the environmental water requirements in the entire basin. The second step uses a sensitivity analysis to finalize the number of dams in the basin by comparison of the basin profits, given by the various number of dams. Finally, the third step of the algorithm investigates the possibility of dams’ capacities reduction, for the selected number of dams while they still provide the same basin profit, given from the first step, using another mixed-integer linear model. The introduced approach was applied to the Sefidrud Basin, Iran and its results showed that three dams could lead to an environmentally sound sustainable economic development for the Basin.     

我国高坝抗震安全评价的现状与挑战

西部地区既是我国水能资源富集的地区,又是我国的地震频发区。高坝大库水利水电工程的建设,有利于减轻下游地区干旱和洪涝灾害,有利于改善能源结构和缓解电力紧张,但地震区高坝抗震安全问题不容忽视。我国在高坝抗震领域取得了不少成绩,但仍不能满足我国高坝建设对抗震安全评价提出的迫切要求。本文根据我国大政方针、现行的法律法规、技术规定,以及有关学科的进展和地震区诸多高坝建设所面临的现实迫切需要,从场址地震动参数确定、大坝设防标准、坝址地震动输入、筑坝材料抗震性能、大坝静动力响应分析、大坝抗震安全评价准则、地震监测和应急预案等方面,系统分析我国大坝抗震安全评价的现状、存在的问题和有关建议,以期为我国大坝抗震安全的研究、分析、设计以及工程运行提供有价值的信息。     

火溪河和涪江上游梯级电站大坝群监测智能系统

介绍了火溪河梯级和涪江上游梯级2库8级电站大坝监测智能系统的实现功能、系统构成、设备选型要求以及实现难点。采用云计算理念和物联网技术,把原先大坝检测人员所需做的工作置于大坝安全管理和技术交流平台上,利用全国有相应资质的大坝工程专家,通过平台对系统内的大坝进行监测和评估,以实现资料共享,由此可以改变目前大坝监测耗时、费力、效果不佳的状态。     

江河开发初探-淮河可持续 发展新前景

淮河在大江大河中水资源开发程度最高且高出甚多，其进一步发展对我国江河开发有重要的参考和示范意义。今流域水资源及水能资源极其贫乏或已开发殆尽，考虑多种形式的抽水蓄能作为常规水电的补充，可使低谷剩余电能转变为尖峰电能。这种引入电网的参与和跨行业的开发模式使各种资源的综合利用可以达到较高的水平，有利于水利水电的可持续发展。笔者建议继续修建(包括扩建和改建)水电工程以及因地制宜地发展风电等可再生新能源。