Strategic Environmental Assessment of Mainstream Dams

In order to understand the long-term implications of the mainstream dam proposals and provide better understanding of the cumulative risks, opportunities and sustainable solutions to the MRC Member Countries, a Strategic Environmental Assessment (SEA) was conducted over a 14-month period. While the benefits of hydropower are potentially considerable for Mekong countries, the construction of one or more of the twelve hydropower schemes could have profound implications for the sustainable development of the basin and irreversibly affect the lives and livelihoods of millions of people in all four Lower Mekong Basin (LMB) Countries.

The SEA holistically assessed all of the proposed twelve hydropower schemes against their cumulative risks, and opportunities. The SEA therefore addresses the broader strategic issues within the mainstream development proposals. The SEA also provides recommendations on how the proposed projects should be best pursued by Member Countries in relation to regional distribution of costs and benefits with respect to economic development, social equity and environmental protection among affected stakeholders.

The SEA Results

The SEA presents transboundary impacts of the proposed mainstream hydropower development projects in the LMB, in the context of the growing number of LMB tributary hydropower projects and storage dams on the Lancang/Mekong River in China. It presents the opportunities and risks associated with the proposed projects while calling for the assurance of equitable development benefits at the national and local levels. The SEA examined four strategic options that range from a 10-year deferral for mainstream hydropower development to pursuing a market-driven development.

The SEA consultant team specifically recommends a 10-year deferral for mainstream hydropower development. The SEA consultants advise that due to the uncertainties regarding the scale and irreversibility of risks in such a complex river system that decisions on mainstream dams should be deferred for a period of up to ten years, with reviews made every three years, to ensure that the necessary conditions to strengthen understanding of the natural systems as well as management and regulatory processes are conducted effectively.

The recommendations of the SEA consultant's team are being carefully reviewed by MRC member countries in particular in relation to the formal process of prior consultation on individual mainstream dams required under MRC's procedures.

Who produced the SEA and what did the SEA process include?

As with any commissioned study, the SEA report is not an official MRC approved document. The SEA was produced by a team of consultants and therefore does not necessarily represent the MRC’s views, conclusions or recommendations. There was a comprehensive stakeholder participation process coordinated and funded through the MRC’s Initiative on Sustainable Hydropower (ISH), a cross-cutting activity working together with all MRC programmes. While conducting the SEA, the SEA consultant team engaged with government agencies, civil society, private sector developers and development partners at both national levels in each of the LMB countries and regionally in its four phases: (i) scoping, (ii) baseline assessment, (iii) opportunities and risks assessment, and (iv) avoidance, enhancement and mitigation assessment. Each phase included the preparation and circulation of a set of reports as the basis for consultation and feedback.

The SEA analysis made use of several years of MRC programme work, especially the work on scenario assessments by the Basin Development Plan Programme, by the modeling team in the Information and Knowledge Management Programme, and the data and studies of the Environment, Fisheries and Navigation Programmes.

Stakeholders' submissions to the MRC regarding hydropower

The MRC has received a large number of submissions from members of the public, civil society and other private organizations. A selection of these can be viewed here. A number of other submissions indicating individual preferences for or against dam projects were also received. View these submissions and MRC's reponses here.

Final Summary Report

Final Full Report

SEA Media Release


Stakeholder Engagement

Documents from other SEA Phases

Click here for access to all documents from:

  • Background Paper
  • Inception Phase
  • SEA Baseline Assessment Phase
  • Impact Assessment Phase (Opportunity and Risks)
  • Avoidance, Mitigation, and Enhancement Phase.

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