Guidelines for hydropower environmental impact mitigation and risk management in the Lower Mekong mainstream and tributaries (ISH0306)

Overview & Background information

    • The MRC Hydropower Mitigation Guidelines (2018) are aimed at providing mitigation guidance for design and operation of hydropower facilities, focused on long term sustainability in the Mekong Basin, to support whole of basin planning and management as well as immediate project development requirements.
    • These Guidelines support the MRC’s Preliminary Design Guidance (PDG, 2009), which may be used by developers during project preparation and then by the MRC to assess projects through its Procedure for Notification, Prior Consultation and Agreement (PNPCA). The Guidelines detail the application of regional and global “good industry practice” for mitigation of hydropower impacts in the Mekong context and shall further enhance the PDG as being updated since 2018 and currently being finalised by Member Countries.
    • As a result of the study risks and impacts of major hydropower development in the Mekong are now well understood and documented; basin scale and system scale planning is critical and urgent to optimise across the energy and water sectors for efficient and sustainable development.

The Initiative for Sustainable Hydropower (ISH) was established with the aim of seeking to embed sustainable hydropower considerations into the regulatory frameworks and planning systems of member countries and into project level planning, design, implementation and operational activities. The ISH 2011-2015 Strategy emphasised this requirement as well as the need to understand the scale and distribution of risks associated with hydropower development on the main stream and on tributaries and also sought the exploration and documentation of possible avoidance, mitigation and benefit and risk sharing options. Besides the Preliminary Design Guidance for Mainstream Dams (PDG) introduced in 2009, necessary frameworks must be in place to provide assurance that risks can be effectively minimised. The ISH sought to enhance these Guidelines and to provide more effective and detailed documentation of the options and methods that may be used to cover the mitigation of hydropower risks in the Mekong based on the latest research and practice from around the world and the region and to expand the applicability of these Guidelines to the tributary developments. During 2016-2018 the work continued with funding from the MRC Basket.

Key Findings of the study:

    1. System and Basin Scale Strategic Planning is vital to avoid large scale impacts and Mitigation must be focussed at a basin scale to support effective project by project mitigation.
    2. Ongoing Cooperation and Benefit Sharing Mechanisms will be valuable to mitigate these basin scale impacts.
    3. Innovative scientific and engineering mitigation options may minimise hydropower environmental and social impact if supported with adequate monitoring and scientific research. However, major environmental risks can only be partially mitigated.
    4. Additional Training and Capacity Building is needed to support the adoption of these MRC Hydropower Mitigation Guidelines

The Guidelines

The study developed a generic practical process for risk and impact mitigation to support Member Countries in their assessment and implementation of mitigation options. The idea is that mitigation is considered not only at the planning, feasibility and design stages of the projects, but also that the effectiveness of mitigation options is monitored and adaptations are made over the project lifecycle. Measures proposed in the study must cover all aspects of the process. The mitigation guidelines will be based on good industry practice and latest research and technical knowhow.

The MRC Hydropower Mitigation Guidelines (2018) provide a clear process and detailed technical guidance to address a range of known risks and impacts in all phases of the Project Development lifecycle:

Guidelines for Hydropower Impact Mitigation and Risk Management in the Lower Mekong Mainstream and Tributaries

A schematic structure of the guidelines is given below:



The MRC Hydropower Mitigation Guidelines comprises with three volumes as series;

  • Volume 1, titled “Hydropower Risks and Impact Mitigation Guidelines and Recommendations” (MRC Hydropower Mitigation Guidelines) summarises hydropower risks, impacts and vulnerabilities as well as key common overarching changes related to hydropower development.
  • Volume 2 is the Hydrowoper Risks and Impact Mitigation Manual - Key Hydropower Risks, Impacts and Vulnerabilities and General Mitigation Options for the Lower Mekong. It supports Volume 1 by describing risks, impacts and vulnerabilities as well as in describing specific mitigation options. It presents examples of good industrial practise mitigation options internationally, from the Greater Mekong Sub-Region (GMS) and the Lower Mekong Basin (LMB).
  • Volume 3 is a Case Study Report describing how promising mitigation options have been modelled and analysed for all mainstream dams. In addition, some conceptual level alternative schemes layout assessments were done both for mainstream dams and those of the Mekong tributaries.

Overall Guidelines Architecture web

Guidelines, Manual, Case Study