Skip to Content


Geography banner

Why dam the Mekong RiverBookmark

Learning area: Geography
Year level: Year 7
Country: Cambodia, China, Laos, Myanmar/Burma, Thailand, Vietnam

This learning sequence explores the mighty Mekong River, its path through six countries, and the wealth it brings. It explores the effect that damming has on the Mekong. Students will participate in a role play simulating a meeting of the Mekong River Commission to discuss the impact of further dams on the Mekong River.

Key inquiry questions

  • Which countries does the Mekong River flow through and how does it affect them?
  • How do human activities affect the Mekong River?
  • How does damming of the Mekong River affect the livelihoods of the people and the river's ecosystem?

Boats filled with people being transported along the Mekong RiverPassengers prepare to disembark from a Mekong ferry


Image: AEF

Related resources

Activity 1: Geography of the Mekong River

In this activity you will construct a map to illustrate the path of the Mekong River from its source to where it flows into the sea and learn about the Mekong River's journey.

Key inquiry question: Which countries does the Mekong River flow through and how does it affect them?

About the Mekong River

  1. Discuss as a class what you know about the Mekong River. You may wish to use the display of materials brought in by members of the class and your teacher to start the conversation.
  2. Create a word cloud about the Mekong River using software such as ‪‪‬‬‬Wordle. Once these are created, discuss which words and/or terms are depicted in the largest font and why this may be so.
  3. Look at the two maps: the Mekong River and the Mekong Basin. Complete the following activities:
    • Identify the mapping conventions that are missing on the map.
    • Describe the path of the Mekong River and the countries it flows through.
    • Predict some of the problems this may cause.
  4. Use the blank map of South-East Asia provided by your teacher to draw and name where appropriate the following, using correct mapping conventions (Border, Orientation, Legend, Title, Scale [BOLTS]):
    • the six countries through which the Mekong River flows
    • the path of the Mekong River
    • the mountainous areas
    • the drainage basin of the Mekong River into Tonlé Sap
    • where the river acts as a border between two countries
    • the delta area where the Mekong River enters the sea.
  5. View the video The Mighty Mekong River to obtain a visual understanding of the physical features of the Mekong River from its source high in the Tibetan Plateau to the mouth at the delta in Vietnam where it enters the sea.
  6. Break into groups of six. Read through the information about the Mekong River Basin below.
  7. Each member of the group should select one of the countries through which the Mekong flows and use notes and the internet to research and collate the following information:
    • the country's population
    • its physical features
    • its key primary and secondary industries
    • its gross domestic product per capita (income earned per person per year).
  8. Collate your notes into a country report, choose a group representative and share your report with the other members of the class. Keep these reports as you will be using them in Activity 3.

The Mekong River's journey

The Mekong is one of the great rivers of the world – and one of those least controlled by humans. It is subject to great variation in height between the wet and dry seasons. In places you can stand at a point where your feet would be wet in the wet season, and look down ten metres to where the level is during the dry season.

For much of the 20th century the area has been the scene of wars, which meant that there was no money or political structure to develop and control the river.

As you read the following description, you will see the term 'Mekong Basin'. That is the area of land draining into the Mekong River. Look at a map showing the physical relief of the area to help you see how it works.

The Mekong begins 5,000 metres above sea level, in the snow-covered mountains of the Tibetan plateau. It drops to 2,000 metres through bleak gorges to enter the Chinese province of Yunnan, where it traverses some of the grimmest, most inaccessible terrain in the world.

The government of Tibet has adopted a deliberate policy of not interfering with the river, as they realise that it is vital to the other countries through which it flows. They are knowingly limiting their own development by this policy.

For the next 1,200 kilometres the Mekong travels south; the topography is still hostile and the river still isolated from much human interference – though this is changing. China is keen to develop Yunnan, one of the poorest provinces of China, and this will involve harnessing the water of the Mekong for hydroelectricity to power industrial development in the area. A dam has recently been built, and already there are factories polluting the water as it leaves China. This pollution dissipates as the river continues its journey.

Having completed roughly half its passage to the sea, descending 4,500 metres on the way and reaching a width of some 400 metres, the Mekong exits China at Yunnan's southern border. Curving south-west, it constitutes the border between Laos and Myanmar for more than 200 kilometres before reaching the Golden Triangle, the point where the river, joined by a small tributary, brings together the borders of three countries: Thailand, Myanmar and Laos. This junction registers the beginning of what is usually termed the 'Lower Mekong'.

What is the relationship of the Thailand, Myanmar and Laos to the Mekong?

  • Of the three countries, Myanmar is least affected by the Mekong's flow, and by any upstream disruption to it.
  • Ninety percent of Laos' population is directly dependent on water and agriculture in the Mekong Basin, but as a number of tributaries flow into the Mekong through Laos, so again this country is not greatly affected by upstream development along the Mekong.
  • Laos's present uses of the water are mainly for fishing, tourism and transport. But Laos is ideally placed to use the water to generate hydroelectricity and to sell that electricity to the industrialising Thailand.
  • Only 36 percent of Thailand's territory is within the Mekong Basin, but that includes its poorest areas. Thailand is looking to use the water to power industrial development in the area, and to enable it to use its neighbours' natural resources. So the Mekong is significant for Thai development.

From the point where the Mekong leaves China, it has only 50 metres left to descend to the sea, which means that it slows down; although there are places where it still flows rapidly through narrows and over rocks.

For a little way beyond the Golden Triangle the Mekong forms the border between Laos and Thailand, but it soon swings east into Laotian territory. Near the ancient Laotian capital of Luang Prabang the river turns south and re-joins the Thai border 250 kilometres later. It continues as the border.

The river now flows smoothly and broadly – up to 1.2 kilometres wide in places – past the Laotian capital of Vientiane, until it flows over the rugged Khone Falls and enters Cambodia, where it is traditionally known as the Thonle Thom. It creates a vast flood plain in Cambodia, until it reaches the Cambodian capital of Phnom Penh.

Nearly all of Cambodia is in the Mekong Basin. Disruption of natural flow upstream would affect Cambodia greatly, as would flood control systems downstream in Vietnam. Cambodia depends on the regular flow of the Mekong for the annual flooding of the Tonlé Sap, a large lake area in Cambodia. During the wet season water actually flows upstream to the Tonlé Sap, as the waters of this tributary cannot enter the fast-flowing Mekong. This regular flood cycle deposits silt for the next season's rice crop, as well as being essential in fish breeding. Changes to this cycle would disrupt Cambodians' lives and economy greatly.

At Phnom Penh the river forks into two streams: the Mekong proper, and the Bassac. The fork creates the apex of the Mekong Delta, a triangular area with its base along part of Vietnam's south-eastern coast. Below the Cambodia–Vietnam border, the Mekong and the Bassac split further and the waters fan out over a richly fertile area of nearly 50,000 square kilometres.

This area, covering only 20 percent of Vietnam's territory but housing over 40 percent of the population, depends on the river floods. The floods dump the silt which is essential for rice growing – the main activity of the area – and also flush out salt which seeps up during the periods of low river flow. A change in the normal flow of the river could bring devastation to Vietnam.

The river finally empties in the South China Sea through numerous mouths; said to be nine, an auspicious number for Vietnamese people. 

Activity 2: Activities on and around the Mekong River

In this activity you will investigate what happens along the length of the Mekong River, and analyse the variation of activities between the wet and the dry seasons and discuss the differences.

Key inquiry question: How do human activities affect the Mekong River?

Analyse water flows and seasons

  1. View the images and videos to identify the different activities that occur along the Mekong River from its source to its entry into the sea. Also have a look at the images on the ‪‪‬International Rivers Lancang (Mekong) River website.
    When the Mekong rises

    This is a documentary film about the Mekong River Commission's Flood Management and Mitigation Program (FMMP).

    Tales of the Mekong Cambodia

    This film shows seasonal flooding of the Mekong and Tonlé Sap, its benefits and life on the lake.

  2. Write notes about the Mekong River using the following headings:
    • seasonal activities
    • fauna inhabits waters
    • flora along the banks.
  3. Pair up with another class member and share your information. Add any information you may have missed.
  4. Read the article on the Mekong/Lancang River at the ‪‪‬‬‬International Rivers Organisation website to find out more about the building of dams, one of the key issues affecting people living on the Mekong River.
  5. Use the interactive pop-up on the map on the page and use the information to create a table (using the appropriate computer software) about the current construction of the dams. Your table should have 6 columns and 23 rows. Label the columns according to the titles below:
    • name of dam
    • location
    • capacity
    • height of wall
    • dam progress.
  6. Use this information to discuss what China is currently building on the Lancang/Mekong River and the potential impact this could have on people living on the Mekong River. Make notes while you conduct your discussion, as you will use this information during the role play in Activity 3: The impact of damming the Mekong River.


Images: AEF

Activity 3: The impact of damming the Mekong River

In this activity you will participate in a role play of a Mekong River Commission meeting as commissioners, representatives of various bodies or people living along the river. You will investigate the effects of damming the Mekong on the people of the lower basin and decide whether damming should occur.

Key inquiry question: How does damming of the Mekong River affect the livelihoods of the people and the river's ecosystem?

Conduct a debate

Your task is to manage potential conflicts over use of the river and decide whether to build dams on the Mekong River. Class members will be commissioners, representatives from different countries and different bodies, and people living on the river. Each will present evidence to the commission for their cause. The role play could be filmed.

Role play: Should the Mekong be dammed?
Roles for participants
The Mekong River Commission

The Mekong River Commission was set up in 1992 to coordinate the development of the Mekong River. Full members include Vietnam, Thailand and Laos. Advisory members are China and Tibet, and Myanmar.

Speaker statements

The following are typical statements from a range of people living in or involved with the Mekong Basin. The various speakers are responding to the proposed or past building of dams at different points along the river.

Cambodian fish biologist

The Pla Buk or Giant Catfish is an extraordinarily large fish. It is unique to the Mekong Basin. If we do not preserve it now, it will disappear under development. The Pla Buk must migrate to spawn, and dams will stop the migration. The Pla Buk is of no great economic significance, but it should not be destroyed.

Laotian farmer

Forestry is a major industry in the area. What will happen to the trees when the area is flooded?

Chinese official

We do not want to damage the river, but industry is necessary for areas of China near the river for us to develop out of poverty. We have no alternative.

Thai archaeologist

This area is the cradle of civilisation, and it is still virtually unexplored archaeologically. Much evidence about human history may be buried here. Once it is flooded for a dam, the evidence will be lost forever.

Thai fisherman

Fishing is a major industry in this region. Hundreds of thousands of tonnes are fished every year. Most local families supplement their income by fishing. When the dam is built there is a danger that it will suit some species which will increase their numbers, but that will drive away all others. So damage will be done to the variety of fish stocks available.

Laotian government official

Our people live in poverty. Infant mortality is increasing. We need to increase people’s standard of living. The development which the dam will bring will achieve this by giving us a product – electricity – that we can sell to other countries which are already developed economically. People who are already developed should not try and stop us from gaining these economic and social benefits as well.

Villagers from several countries in areas to be flooded by a proposed dam

What about us? We people who live in the area will lose our homes, our land, our livelihood.

Laotian boatman

Dams will improve navigation along the river as it will be possible to travel on the river all year once dams regulate the flow. This will increase business and tourism and will make goods more readily available to people.

Vietnamese ecologist

Flooding will cause a loss of habitat for some large animals and land-based birds, though water birds will increase greatly.

Tibetan politician

Tibet will not be affected, because we have the source of the river. We are keen to keep the river as natural as possible and will not develop it or pollute it for others downstream, but that means we are losing potential revenue which could improve the standard of living for our people. We think other countries should pay us some compensation for this.

Cambodian agriculturalist

The dam will hold back destructive flood water and allow plenty for the dry seasons, so areas now unproductive can grow rice through irrigation. This will be a wonderful advantage for many areas.

Use the above text, and the information gathered in the previous activities, to assist with the structure of your presentations or judgements.

  1. Discuss how the meeting will proceed and nominate a chairperson. Create a shared list of protocols such as respectfully listening to each others' presentations and not calling out.
  2. Determine who will play the various roles in the role play.
  3. Gather information that you will need to support your role, write your presentation and practise delivering it. Presentations should be about two minutes each.
  4. If you are going to film the proceedings, set up the room and gather the props.
  5. Start the role play by having the chairperson describe why the meeting is occurring and providing the order of proceedings. Make sure you have someone taking notes.
  6. Once all the evidence has been presented, the commissioners should discuss the presentations and cast their votes.
  7. Complete the activity by discussing how you felt about the decision-making process.


Text: adapted from Vietnam Young People Old Country: Secondary pp 26–40 © Education Services Australia and University of Melbourne

Activity 4: Reflection

To conclude this learning sequence you will reflect on what you have learned about the damming of the Mekong River and compare it to the Murray–Darling River Basin in Australia.

Discuss and reflect on the similarities and differences between the Mekong River and the Murray–Darling River Basin System in Australia.

Consider the following questions:

  • Is it important to consider the ecology of the river and the possible extinction of animal and plant species in the name of progress?
  • Are hydroelectricity and irrigation dams worthwhile?
  • Should one country or state benefit at the expense of another?
  • How do countries reach compromise?
  • Do all participants have equal power?

This learning sequence provides students with the opportunity to explore the Mekong River, the countries it flows through and the impact damming has on people living on and by the river. 

Activity 1: Geography of the Mekong River

Prior to beginning this activity, ask your students to bring to class any photographs, magazine articles, brochures or items associated with life on and along the Mekong River. These can be used as a stimulus for class discussion and for you to assess students' prior knowledge about the Mekong River.

Explain that the main focus of the learning sequence is for students to participate in a role play where they will participate in a meeting of the Mekong River Commission where the commissioners will decide whether the Mekong River should be dammed.

The preceding activities will provide them with information to assist them to make their judgements. Provide students with a paper copy of the South-East Asia map provided in the activity notes and use it and the images, videos and information to explore the physical attributes of the Mekong River and the countries it flows through.

Activity 2: Activities on and around the Mekong River

In this activity students will investigate the activities that occur on and by the Mekong River. They will use the maps, images and videos from the web page, and images from the ‪‪‬‬‬International Rivers at Lancang (Mekong) River website, to take notes. These will be used to assist their decision-making in Activity 3.

Activity 3: Should the Mekong be dammed?

The focus of this activity is to conduct the role play and work through a decision-making process. Your students will use the information they have gathered in activities 1 and 2 to decide whether the Mekong River should be dammed. Below is a table of the current status of dams being built on the river, to help you set the scene with your students.

History of Mekong River Commission

Until the 17th century, the estuary swamps and forests of the Mekong Basin were virtually uninhabited. Following Vietnamese settlement of the delta, the area became subject to regular conflict between Vietnamese, Cambodians/Khmer and Thais until the French colonists took control in the mid-19th century.

France took control of Indochina but in 1953 divided it into three autonomous territories: Laos, Cambodia and Vietnam. In 1954 France was defeated. In 1992, the Mekong River Commission was established to oversee issues pertaining to the river.

The table below is adapted from the ‪‪‬‬‬‬Mekong River Commission For Sustainable Development website. Please use the legend provided when working with the table.

The resources contained in the activity will provide students with information about the role play. It is important that your students discuss and agree on how they will conduct the role play and any special protocols to be used.

Activity 4: Reflection

To conclude this learning sequence, students are asked to compare and contrast the Mekong River with the Murray–Darling River Basin in Australia and consider the impact of damming. This activity will allow you to assess the level of conceptual understanding that has resulted from teaching this module.

Dams along the Mekong: water flows
Name of dam Status County district Installed capacity (MW) Dam height (m) Expected migration
Cege P Kham county T 160 U U
Yuelong P Zhag’yab T 100 U U
Kagong UC Zhab’yab T 240 U U
Banda P Zogang T 1000 U U
Rumei P Markam T 2400 U U
Guxue P Markam T 2400 U
Gushui P Deqin Y 2600 220 3776
Guonian Canc 2012 Deqin Y 1200 165 2970
Wunonglong UC Deqin Y 990 137-292 808
Lidi UC Weixi Y 420 74 575
Tuoba P Weixi Y 1250 158 5951
Huangdeng UC Lanping Y 1900 202 4415
Dahuaqiao UC Yunlong Y 900 106 U
Miaowei UC Yunlong Y 1400 139.8 11036
Gongguoqiao UC Yunlong Y 900 130 4596
Xiaowan C 2010 Nanjian Y 4200 292 28 748-32 737
Manwan C 2007 Jingdong Y 1550 126 3042
Dachaoshan C 2003 Jingdong Y 1350 118 5200-6052
Nuozhadu C 2012 Simao d Y 5850 261-265 4300
Jinghong C 2009 Jinghong city Y 1750 118 1700-2264
Mensong canc Dinghong city Y 600 65 230

P: Status planned
UC: Under construction
C: Completed with year of completion
Canc: Cancelled

Country district
T: Tibet
Y: Yunnan

Installed capacity
MW: Megawatt

Dam height/expected migration
U: Unknown

Compiled by Wendy Connor based on the ‪‪‬Mekong River Commission For Sustainable Development website.

Useful websites

It is recommended that teachers preview websites to ensure they are suitable for their students prior to use in class. Content accessed via these links is not owned or controlled by Asia Education Foundation and is subject to the terms of use of the associated website. 

The full resource can not be displayed on a mobile device.

back to top