The FAQs are also available in Khmer, Lao, Thai and Vietnamese.

 1. What is the MRC’s Prior Consultation process?

Prior Consultation is one of three processes of the Procedures for Notification, Prior Consultation and Agreement (PNPCA). The Prior Consultation is a process for the MRC’s Member Countries to discuss and evaluate benefits and associated risks of any proposed water-use project which may have significant impacts on the Mekong River mainstream’s flow regimes, water quality and other environmental and socio-economic conditions.

Any Member Country (notifying country) who intends to proceed with the project is required to notify the other countries (notified countries) and provide them with available data and information. The process enables the notified countries to assess possible impacts on their territories and comment on the proposed use.

The process aims for the Joint Committee (JC) – a body consisting of four Member Countries’ representatives at the head of departmental level where the Prior Consultation takes place – to reach an agreement to achieve an optimal use and prevention of waste of water, and to issue a decision that contains agreed upon conditions for the project.

The Prior Consultation is not about approving the proposed water use; rather it is designed for the notified countries to make recommendations and for proposing country to accept certain measures to avoid, minimise and mitigate any potential adverse transboundary impact and to find a better way to share the benefits.

This is because, as stipulated by the PNPCA, the Prior Consultation is neither a right to veto the proposed use, nor a unilateral right to use water by any Member Country without taking into account the others’ rights and concerns.

2. Do the other three notified countries have the right to veto or oppose the project? 

No, they don’t. 

The 1995 Mekong Agreement clearly states the Prior Consultation process is neither a right of any country to veto a project, nor is it a right of any country to proceed with a proposed use of the river without taking into account the other riparian countries’ rights and concerns. 

3. Is the Prior Consultation the approval process that is needed for a proposed project? 

No, it isn’t. 

The Prior Consultation is not a process to seek approval from any Member Countries for the project. Instead, it provides an opportunity for the notified countries to review the project and raise their legitimate concerns on adverse transboundary impacts on the environment and their people, if any. It also allows the country proposing the project to better understand such concerns and to identify measures to address them. 

For example, as part of the efforts to address the concerns raised by the other Member Countries during the Prior Consultation for the Xayaburi Hydropower Project, the Lao Government has made significant improvements to the project’s design to avoid, minimise and mitigate possible impacts. The Lao Government and the developer significantly invested to revise their dam’s design to address the issues of fish migration and sediment, two of the main concerns raised during the Prior Consultation. 

4. Does the 1995 Mekong Agreement specify the types of projects that should undergo this process? 

Yes, it does. 

The 1995 Mekong Agreement and the PNPCA specify the types of projects based on geographic locations and how water resources in the Lower Mekong Basin will be used at particular seasons during the year. 

The run-of-river project located in the Mekong mainstream is required to go through the PNPCA process. In addition, the Mekong Agreement and the PNPCA call for Prior Consultation if these projects are deemed to have significant impacts on the Mekong mainstream’s flow regimes and water quality which are transboundary in nature. 

Moreover, three types of water-use or diversion projects that must undergo the Prior Consultation include:

  1. Any mainstream project using water within the Lower Mekong Basin during the dry season
  2. Any project diverting water from the Mekong mainstream to any other basin during the wet season, and
  3. Any project diverting the surplus quantity of water to any other river within the basin during the dry season.

Application of PNPCA process under the 1995 Mekong Agreement of the MRC


5. How long does the Prior Consultation take? 

The process normally takes six months. If the Joint Committee requires more time for discussion, the process can be extended. 

6. What will happen during the Prior Consultation process? 

When the MRC Joint Committee Working Group (JCWG) meets for the first time after receiving the notification with the project’s documents, it decides on the starting date of the Prior Consultation process. The JCWG comprises senior technical representatives from Cambodia, Lao PDR, Thailand and Viet Nam and acts as an advisory body to the MRC’s Joint Committee in implementing the PNPCA 

Over the six-month course, the Joint Committee reviews technical aspects of the project to determine compliance with the MRC’s procedures on flow regime and water quality, assesses any possible impact on environment and livelihoods, and suggests measures to address those concerns before concluding the process. 

The review will determine compliance with the MRC’s Preliminary Design Guidance for Proposed Mainstream Dams in the Lower Mekong Basin, published in 2009 (PDG 2009). 

Although public involvement is not a requirement of the process, the Member Countries have agreed to the importance and involvement of stakeholder participation. At the national level, national information sharing/stakeholder consultation meetings will be held accordingly and followed national mechanisms and practices in the respective countries. 

At the regional level, regional information sharing/stakeholder consultation meetings will be held, too. Field visits to the project will also take place. 

A Technical Review Report, which includes findings from the national information sharing/stakeholder consultation meetings, will be presented to the Joint Committee. 

After that, the notified countries will submit their Official Reply Forms to the MRC Secretariat to have their comments recorded. 

The final stage is for the Joint Committee to hold a meeting to discuss the project’s Prior Consultation with an aim to reach an agreement to achieve an optimal use and prevention of waste of water, and to issue a decision that contains agreed-upon conditions for the project. 

A road map of the six-month process will be made available here once the JCWG approves it. 

7. Can such agreed-upon conditions be adapted later during the project’s construction or operation? Could there be any additional conditions imposed at this stage?

Such conditions may be considered even after the Prior Consultation process is completed. This is because the 1995 Mekong Agreement defines ‘agreement’ on conditions to be made under the Prior Consultation process as a dynamic and practical consensus. 

A joint action plan, such as the one for the Pak Beng and Pak Lay projects, is now an established mechanism to consider additional measures for the notifying country to consider, if agreed by the Joint Committee, and for the MRC to follow up in terms of recommendations and monitoring. 

8. What could any other Member Country do if it finds out later that the environment in its territories has been significantly affected by the project? 

The 1995 Mekong Agreement provides a framework for prevention and cessation of harmful effects. 

The country encountering such impact should notify the MRC of the incident with valid evidence and the country causing that impact would need to immediately cease the alleged cause of harm until that cause is determined. The Mekong Agreement also specifies state responsibility for damages once determined by the concerned parties, in conformity with the principles of international law. 

9. Is it mandatory for the Joint Committee to reach an agreement on the Prior Consultation for a proposed project? 

No, it is not. 

It is not mandatory for the Joint Committee to reach an agreement before implementing the proposed use. The PNPCA states that the Joint Committee should aim to arrive at an agreement. If the Joint Committee cannot reach an agreement, its views will become part of the record of the proposed use for future reference. The final decision to proceed or not proceed with the project rests with the country proposing it, after it has duly considered and addressed in good faith all the legitimate concerns of notified countries and stakeholders. 

10. What happens if the Joint Committee cannot reach an agreement on the Prior Consultation process or agree on conditions to achieve an optimal use or prevention of waste of water? 

If the Joint Committee cannot reach an agreement on the Prior Consultation process, they may refer the matter to the higher MRC governing body, the MRC Council, which consists of water and environment ministers from the four Member Countries. 

If the Council cannot decide on the issue, it may refer this to the governments of the four countries to seek resolution through diplomatic channels. Should the governments find it necessary, by mutual agreement, they may request for mediation and proceed according to the principles of international law. 

11. Why does the MRC need the Prior Consultation? What are the benefits of the process? 

Proposed water-use projects that call for the Prior Consultation are more likely to have significant impacts on the environment and people and, therefore, should afford the other countries the opportunity to evaluate and comment on them. 

The Prior Consultation process aims to prevent, minimise and mitigate adverse significant cross-border adverse impacts on riverine communities and the environment upstream and downstream. It also intends to achieve the optimal use and prevent waste of water. 

The MRC has so far experienced five Prior Consultation cases – Xayaburi, Don Sahong, Pak Beng, Pak Lay and Luang Prabang hydropower projects. These projects are situated in the Mekong mainstream in Lao PDR. They all show progressiveness of the 1995 Mekong Agreement implementation and the MRC itself, the legendary Mekong spirit of the Member Countries’ cooperation. 

For Xayaburi, the process has prompted the Lao government and the developer to conduct their own environmental impact assessment and to significantly invest additional hundreds of millions of US dollars to revise the dam’s design to address the issues of fish migration and sediment, two of the main concerns raised during the prior consultation. Similar improvements were also made to the Don Sahong project. 

In the cases of Pak Beng and Pak Lay, the Joint Committee reached an agreement at the end of its six-month Prior Consultation process. The body issued a Statement, and subsequently, a Joint Action Plan (JAP) to provide mechanisms for ongoing feedback, data exchange, and knowledge sharing as well as joint monitoring between Lao PDR and the MRC concerning the ongoing design, construction, and operation of the project. 

Without the Prior Consultation process, there is no open information sharing and consultation for projects of sovereign countries. Without Prior Consultation, projects will not have opportunities to be improved through independent recommendations. The Prior Consultation process requires scientific assessments and facilitation by a professional and impartial team from the MRC Secretariat. It strikes a balance between the interests of the four Member Countries and social and environmental sustainability of the Mekong river basin. 

Specifically, regardless of one’s views on the proposed project, the MRC’s PNCPA is indispensable because:

  • It allows extensive data and information about a major infrastructure project of a country to be shared in public
  • It provides an official, legitimate and safe platform for all countries and stakeholders to air different views and suggestions after full consideration of the information provided
  • It allows an independent review and recommendations from experts from the MRC, Member Countries as well as NGOs regarding the project
  • It results in concrete improvement and adaptation of the proposed projects
  • It results in a mechanism of a Joint Action Plan to further engage with the project as it further develops after the PNPCA, including joint monitoring of impacts.

All of these keep the proposing country engaged and accountable. The absence of the PNPCA and the MRC would allow projects on the Mekong to proceed as they wish without much information or review by the public.

12. Who will be involved in the Prior Consultation process?

The Prior Consultation is undertaken by the MRC Joint Committee and supported by the MRC Secretariat in its technical and administrative functions. Each National Mekong Committee and its Secretariat provide national administrative and coordinating functions, and supports the Joint Committee in the implementation of related activities. 

A Joint Committee Working Group (JCWG) acts as a technical advisory body to assist the Joint Committee during the implementation of the PNPCA. The JCWG, with support from the MRC Secretariat, will review aspects, such as water flow, dam safety, fish migration, sediment flow, navigation and environmental and socio-economic impacts. 

Civil society organisations and members of the public will be engaged by the respective National Mekong Committee in each country during the national information sharing/stakeholder consultation. 

At the regional level, two regional stakeholder consultations are proposed for the Sanakham Hydropower Project, which call for public participation and contribution.   

13. What is the role of the MRC Secretariat in the process?

The MRC Secretariat will assist the Member Countries to assess technical aspects of the project and facilitate meetings of the Joint Committee. 

The MRC Secretariat, together with the National Mekong Committee Secretariat in each Member Country, will facilitate national and regional stakeholder consultations in order to solicit views and concerns from different stakeholders and other interested parties on the case to the proposing country for its consideration. The MRC Secretariat will facilitate consultations with stakeholders in good faith and systematically document their views and demonstrate how those views will be considered by the MRC governing bodies and provide feedback on them. 

After the Prior Consultation is completed, the Secretariat can continue to offer technical input to the project, if needed.

15. What issues will be considered during the technical review of the project’s submitted documents?

The technical review looks at the overall concept of the proposed project according to the submitted feasibility study and the Environmental and Social Impact Assessment. 

It will evaluate the project against the Preliminary Design Guidance for Proposed Mainstream Dams in the Lower Mekong Basin, published in 2009 (PDG 2009) and will identify gaps and revisions if needed. The PDG 2009 provides direction on performance targets, design and operating principles for mitigation measures, as well as compliance monitoring and adaptive management. It will also address particular issues as decided by the Joint Committee Working Group. 

15. How does the on-going update of the Preliminary Design Guidance for Proposed Mainstream Dams in the Lower Mekong Basin (DG 2020) contribute to this Prior Consultation process?  

The technical review will mainly consult the PDG 2009, as this is the only approved framework upon which the review can be based. However, efforts will also be made to comment on, refer to and suggest, where relevant, the project developers and Lao Government to those gaps and areas of ambiguity found in the PDG 2009 after its implementation on the three previous cases, and filled and clarified by the DG 2020 along with the organisation’s updated knowledge. 

16. How organisations or stakeholder groups will be engaged at stakeholder consultations or information sharing meetings?  

Responsibility for holding in-country consultations or information sharing meetings rests with the respective National Mekong Committee – a government coordination body of each of the Member Countries –  and is coordinated by the NMC Secretariats. The MRC Secretariat will render technical support. 

Considering lessons learnt from the four previous cases of Xayaburi, Don Sahong, Pak Beng and Pak Lay, as well as the current case of Luang Prabang, the MRC Secretariat has started to engage concerned stakeholders from the outset in the Prior Consultation process. Information has also been widely and transparently shared on the MRC website

The MRC Secretariat is also aware of the necessity of giving sufficient time to the public to review the project documents, hence making the project documents available also on a dedicated webpage for the Sanakham hydropower project.

The webpage, which houses these documents, is accessible here: 

The Secretariat has put together a 29-page long overview/summary of the many technical documents submitted for ease of access, available on the same webpage. This overview document will soon be available in the four riparian languages for wider access by the public. 

Other relevant documents will be made available on a timely fashion during the process, including presentations and fast facts about the proposed project. 

There will be two stakeholder consultation meetings at the regional level and many information sharing and stakeholder consultations for affected communities at the country level. To facilitate broader stakeholder participation, participants from all sectors – NGOs, community-based organisations, research institutions, academia, developers, media and others – are especially welcome. The MRC will provide financial support for participants from highly relevant organisations if they face financial difficulty. 

The MRC works on its participatory approach through collaboration, stakeholder participation and community engagement during the implementation. The MRC greatly values voices and concerns of the stakeholders and interested parties for the people’s well-being on the Mekong basin. The MRC Secretariat is doing its best to support the Mekong countries to transform policies into practice to ensure the sustainable development and management of the Mekong River basin. 

During the Prior Consultation process, we strive our best to improve the MRC stakeholder engagement strategy with on-going process, including information sharing, stakeholder fora and consultations. The MRC welcomes comments and feedback from all the concerned stakeholders through our active comment box, hosted on the MRC website and accessible here: 

17. Are there representatives of the civil society organisations in the Joint Committee Working Group (JCWG)? 


There is no representation of the civil society organisation in the JCWG, which is a technical advisory body of the four member governments and was formed to guide the MRC Secretariat in facilitating the process and to discuss emerging issues. 

The JCWG’s function is to also assist the MRC Joint Committee in implementing the PNPCA and to provide necessary guidance to the MRC Secretariat in relation to those notified projects that call for Prior Consultation or agreement according to the principles and steps set out in the 1995 Mekong Agreement. Its formation is provided for in the MRC Procedures. Membership comprises four representatives from each of the four lower Mekong countries, with the MRC Secretariat providing technical and administrative input to them. 

However, official and other comments from the public documented at the Regional Stakeholder Forums, national meetings and other channels will be raised at the JCWG and the JC.

18. How will the MRC use collective perspectives of stakeholder groups in the Prior Consultation process? 

Stakeholders’ input, views and comments will be reflected in a “comments matrix” to be documented in a stakeholder consultation report that will be considered during the evaluation of the project. 

Findings and recommendations from the regional information sharing report, together with the national information sharing report, will be documented in a Technical Review Report (TRR) and presented to the MRC governing bodies for consideration during negotiation on conditions for the project. 

19. How much information about the project will be made available to stakeholder groups and the public?  

The MRC has already made available “all” the submitted project documents on its website, which is accessible to the public. 

These are: transboundary environmental and social impact assessments and cumulative impact assessment, environmental impact assessment, environmental management and monitoring plan, social impact assessment, social management and monitoring plan and resettlement development plan. An engineering status report and drawings are also available on the same webpage, hosted under the MRC website at: 

On-going and future documents related to this Prior Consultation will also be made available on the same webpage. These include, among others, the MRC’s technical review of the project’s documents, stakeholder consultations report, and official reply forms submitted by the three notified countries of Cambodia, Thailand and Viet Nam. 

20. Could construction begin during the Prior Consultation? 


Under the PNPCA, the notifying country must not implement the proposed water-use without providing the opportunity for the notified countries to discuss and evaluate the project. 

21. Could the outcome of Prior Consultation for any project set a precedent for future projects that will be submitted for the same process? 


The Prior Consultation process is conducted on a case-by-case basis for each proposed mainstream development project. If a future project of similar type is submitted to the MRC for Prior Consultation, the outcome of any previous consultation will not affect the newly proposed project. But information and knowledge gathered during any previous Prior Consultations will be useful to future projects and can be used as a part of the baseline information for evaluation. 

In 2016, the MRC reviewed the implementation of the PNPCA adopted under the 1995 Mekong Agreement and documented for reference some key lessons learnt. Those key lessons learnt are:

  • greater clarity regarding the commencement and conclusion of the Prior Consultation process
  • a process for the review and approval of the adequacy of documentation received for Prior Consultation
  • greater clarity regarding the roles of all actors who have a responsibility for implementing the PNPCA
  • development of appropriate project information disclosure practices to effective stakeholder participation
  • greater clarity regarding the role of transboundary EIA (environmental impact assessment), and
  • development of a “Commentary” on the provisions of the PNPCA, to supplement the current Guidelines on Implementation of the PNPCA by placing the key provisions of the PNPCA in the wider context of international best practice in the field. 

The Prior Consultation process for Pak Beng, Pak Lay and Luang Prabang projects took those lessons learnt into consideration during their implementation. We expect the same will be applicable in the case of the Sanakham project.

22. How do findings from the Council Study (study on sustainable management and development of the Mekong river including impacts of mainstream hydropower projects) contribute to the Prior Consultation process?

The main objective of the Council Study is to further enhance the ability of the MRC to advise Member Countries on the positive and negative impacts of water resources development on people, economies and the environment of the Mekong River basin, with a focus on improving the understanding of the sustainable development of the Mekong River.

Council Study’s scope of work covers all water-related sectors such as irrigation, agricultural land use, fisheries, navigation, domestic and industrial water use and hydropower focusing on the mainstream development projects. The Study also considers other important disciplines such as hydrology and its related issues, biodiversity, environment, socio-economics, macroeconomics and climate change. In addition, transboundary impact assessment employs a full range of indicators for the above sectors and disciplines. 

In general, because of the Council Study and previous assessments by the MRC, the Member Countries are increasingly aware of the opportunities and risks of hydropower projects on the mainstream. 

Specifically, for the PNPCA, the Council Study plays an important role as knowledge, information, data and assessment tools to support any impact assessment work for the Prior Consultation process of the specific mainstream development project.  

23. Is transboundary impact assessment a requirement of the Prior Consultation process? How are transboundary impacts of the project viewed and used?

According to the PNPCA, transboundary impact assessment, either socio-economic or environmental, is not mandatory since none of provision obliges the notifying country to do such assessment.

However, it is essential for the notifying country to provide such assessment information to enable the notified countries, as well as the MRC Secretariat, to evaluate and discuss measures to minimise and mitigate potential cross-border impacts. For this reason, the newly updated PDG also includes this missing aspect.