Balancing River Health and Hydropower Requirements in the Lancang River Basin

Hydropower development is the primary issue affecting river health and aquatic ecosystems in the Lancang River Basin and potentially more broadly within the Lancang-Mekong River (Grumbine et al. 2012; Fan et al. 2015). Nevertheless, hydropower developers lack adequate knowledge on the impacts of hydropower projects on river health in general and on how best to mitigate and compensate for adverse effects. Although numerous studies both in China and abroad have assessed the impacts of hydropower projects on the river ecosystem in the Lancang River Basin, few studies have applied a river health perspective that integrates ecological and human values. It is also apparent that institutions and communities in countries downstream of China, along the Lancang-Mekong River, do not have adequate knowledge to understand transboundary environmental effects of hydropower projects, the opportunities to influence hydropower development on the Lancang River, or the way in which water regulation is managed. Another substantial knowledge gap is the impacts of hydropower development on women, which may be greater than those on men; these impacts have not been considered in China. Protection of environmental resources and social values during hydropower development in the Lancang River Basin is most effectively achieved with a cooperative approach in which skills, experiences, and lessons learned are shared at local and international scales.

To frame and guide our river health assessment, we collated and reviewed information and documents relevant to the study of river health and hydropower impacts on river health. Literature that was considered for review included Chinese and international scientific peer-reviewed publications, industry reports, publications by government and nongovernment organizations, and reports on technical standards and protocols. Relevant literature sources were compiled, reviewed, and analyzed to frame our assessment of river health, to assist with the selection of appropriate indicators, and to understand the current status of Lancang River health and how hydropower has influenced river health.

Chapter 2 identified components of river health that are in poor or critical condition and have been adversely affected by the development of hydropower. In this chapter, we review the existing mitigation, management, and monitoring activities that are employed on the Lancang River and make recommendations for improvements that, if implemented, will further mitigate the adverse effects of hydropower development.

The Lancang River Basin in China is undergoing extensive hydropower development, and several large dams on the upper Lancang-Mekong River have become operational in the last 20 years. The Lancang-Mekong River flows through Myanmar, Laos, Thailand, Cambodia, and Vietnam after leaving China; thus impacts of the development of the Chinese Lancang cascade of hydropower projects may extend well beyond national boundaries. Transboundary effects may be both positive and negative. For example, although natural ecosystems have the potential to be negatively impacted, water management may alleviate some of the negative effects of drought or flood.

Downstream effects of the Lancang cascade of hydropower projects on water temperature were investigated through temperature data comparisons and modeling. Similar to the approach for hydrology (Chap. 4), comparisons of water temperature were conducted in part by comparing water temperature between baseline (historical) and post-project periods. Other comparisons were also made, such as comparing post-project water temperature upstream and downstream of a hydropower project and comparing temperature gradients within different river segments and during different time periods. Modeling of actual and virtual development scenarios, in which the effect of a hydropower project could be included or removed, was also used to investigate the consequences of the presence of a particular hydropower project on water temperature. Water temperature data were compiled from existing hydrological stations along the Lancang-Mekong River Basin (MRC data) and additional data collected from gauges installed specifically for the study.

Downstream effects of the Lancang cascade of hydropower projects on sediment load, sediment transport, and river channel geomorphology were investigated through a combination of literature review and analysis of suspended sediment data recorded at hydrological stations in the Lancang-Mekong River. For the analysis of sediment transport and channel morphology, it was first important to establish the background necessary to put potential changes due to hydropower projects into perspective. An understanding of sediment transport and channel morphology, and the potential for hydropower projects to affect these processes, is dependent on an understanding of the physical, biological, and anthropogenic factors that affect them. These include sediment yield of the adjacent land base through soil erosion, sediment load and transport within the river system, and key aspects that govern channel morphology. Providing background material on these topics required a thorough literature review and compilation of information relevant to our analysis of transboundary effects.

A growing number of studies are providing evidence that dam construction and operation of hydropower projects can lead to undesirable ecological responses in rivers (Nadon et al. 2015), and the influence of dams on fish diversity has become a major environmental problem (Ziv et al. 2012). Hydropower dams can lead to fish habitat fragmentation, obstruction of dispersal and migration movements, and loss of habitat, including spawning habitat, which has been directly linked to the loss of populations and species of freshwater fishes (Nilsson et al. 2005; Petesse and Petrere 2012; Gao et al. 2013).

Beginning in the mid-1980s, China began to adhere to policies set out by the World Bank requiring the assessment of forced resettlements as an integral and mandatory component of infrastructure projects (Cernea 1998). Nevertheless, until recently, hydropower developers did not comprehensively consider the social impacts of their projects and consequences to livelihoods resulting from the displacement of people.

Laos, officially the Lao People’s Democratic Republic (Lao PDR), is a country rich in hydropower resource potential, and the Laotian government is actively seeking to develop the hydropower industry with the goal of becoming the “Battery of Southeast Asia.” The regulatory and technical capacities of environmental management of the hydropower sector in the Lao PDR are relatively weak but are steadily improving due to capacity building through national and international institutions. China has a rich history of experience and lessons learned over almost 40 years in the development and environmental management of hydropower that can be shared to facilitate sustainable hydropower development in the Lao PDR. The objective of sharing experiences and lessons in the Lancang River along with international best practices with the Lao PDR is to increase the level of knowledge and skills of the hydropower and regulatory agencies regarding environmental impacts and mitigation measures for hydropower development.

This book has presented key components of a Project funded by the CGIAR Research Program on WLE focused on ecological and social effects of hydropower development on the Lancang River. Objectives of this Project were to investigate and address key ecological and social issues, within China and in countries downstream, related to hydropower development on the upper Lancang-Mekong River in China, and to make recommendations for improvement. In accordance with the broad scope of this Project, there were many goals, some of which were the acquisition and compilation of information, whereas others were applied, with a focus on facilitating positive change. The investigations and analyses presented in this book are an important component of the tasks required to meet the Project’s goals by investigating and identifying key issues that communication and collaboration can then further address.