CENTRO ALTI STUDI PER LA DIFESA ISTITUTO ALTI STUDI PER LA DIFESA

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1 CENTRO ALTI STUDI PER LA DIFESA ISTITUTO ALTI STUDI PER LA DIFESA 3 rd International Capstone Course Individual Paper Impact of Major dams development on Mekong river on fisheries and environment Col. TRAN XUAN CHINH VIET NAM Rome 24/04/2015

2 Table of Contents Table of Contents 2 1. Introduction 3 2. Hydropower in the Mekong River Basin 3 3. Mekong Mainstream Dams 4 4. Impact of dams development on the Mekong fisheries 9 5. Some proposed solutions Conclusion Bibliography 15 2

3 Topic: Environment and Armed conflicts 1. Introduction Impact of Major dams development on Mekong river on fisheries and environment The Mekong River runs more than 4,000 kilometers, from China into Myanmar and then through Laos, Thailand, Cambodia and Vietnam, where it empties into the sea. Traditionally a major transport route and food source, it is also increasingly becoming a supply of energy at its own peril and at the cost of instability among states in the region. Several large dams already straddle the Mekong in China, and construction on more dams downstream is underway. Hydropower is a well-established source of renewable energy, and the countries of the lower Mekong see it as an attractive way to help meet their exploding energy demand while diversifying their energy portfolio. Over 80 percent of Thailand s total energy consumption, for example, is satisfied with fossil fuels. With a massive dam under construction in Laos and other dams on the way, the Mekong River is facing a wave of hydroelectric projects that could profoundly alter the river s ecology and disrupt the food supplies of millions of people in Southeast Asia. 2. Hydropower in the Mekong River Basin The estimated hydropower potential of the lower Mekong Basin (i.e. excluding China) is 30,000 MW, while that of the upper Mekong Basin is 28,930 MW. In the lower Mekong, more than 3,235 MW has been realized via facilities built largely over the past ten years, while projects under construction will represent an additional 3,209 MW. An additional 134 projects are planned for the lower Mekong, which will effectively exhaust the river s hydropower generating capacity. The single most significant impact both now and in the future on the use of water and its management in the Mekong Region is hydropower. 3

4 Given current development trends in the region, power demands are expected to rise 7% per year between 2010 and 2030, yielding a substantial and potentially lucrative - energy market. Hydropower is the favoured energy option for the Mekong s riparian countries, as reflected in the narratives utilised to support these interventions. Laos is being portrayed as the battery of Southeast Asia. In China, hydropower is promoted as the best possible ( clean green ) alternative to their coal-fired power stations, and will open the way to the development of the west. In Thailand, hydropower champions emphasise the greening of Isan, the drought-prone northeast, to legitimise the development of a spectacular water grid that will channel water from Laos, under the Mekong mainstream, and, according to critics, over-emphasise projected energy demands in the country. In Cambodia, hydropower is often seen as central to solving the country s energy supply problems. The development of the Mekong River Basin is highly controversial, and is one of the most prominent components in the discussion about the river and its management. This debate occurs in both the academic literature, as well as the media, and is a focus for many activist groups. 3. Mekong Mainstream Dams The revival of plans to build a series of dams on the Mekong River's mainstream in Cambodia, Laos, and Thailand presents a serious threat to the river's ecology and puts at risk the wellbeing of millions of people dependent on the river for food, income, transportation and a multitude of other needs. Since the 1960s, several mega-schemes to dam the Lower Mekong River's mainstream to generate electricity have been proposed. The most recent plan, prepared by the Mekong Secretariat in 1994, was shelved in part due to public outcry over the predicted impacts on the river's fisheries and the large number of people who would be displaced or otherwise affected. But now there are troubling signs that the tide is turning. Since mid-2006, the Governments of Cambodia, Laos and Thailand have granted approval to Thai, 4

5 Malaysian, Vietnamese, Russian and Chinese companies to investigate eleven mainstream hydropower dams. The projects are located at Pak Beng, Luang Prabang, Xayaburi, Pak Lay, and Sanakham in northern Laos; Pak Chom and Ban Koum on the Thai-Lao border; Lat Sua and Don Sahong in southern Laos; and Stung Treng and Sambor in Cambodia (see map). That these projects are once again being actively investigated is cause for alarm. Already serious concerns have been raised by non-governmental organizations and scientists over the Xayaburi Dam, which is at the most advanced stage of development. In September 2010, this dam became the first mainstream dam to be submitted for approval by the region's governments through a regional decision-making process called the "Procedures for Notification, Prior Consultation and Agreement" (PNPCA), facilitated by the Mekong River Commission (MRC). This leapfrogged the publication of the MRC's Strategic Environmental Assessment report by a mere three weeks, which provided a critical appraisal of the dam plans and recommended that decisions on whether to proceed with the mainstream dams be deferred for a period of ten years until further studies can be conducted to ensure that decision-makers are fully informed of the risks. With so much at stake, it is crucial that the Mekong region's decision-makers endorse and adopt the SEA's recommendations before it's too late. China's dam construction on the Upper Mekong has already caused downstream impacts, especially along the Thai-Lao border where communities have suffered declining fisheries and changing water levels that have seriously affected their livelihoods. By changing the river's hydrology, blocking fish migration and affecting the river's ecology, the construction of dams on the Lower Mekong mainstream will have repercussions throughout the entire basin. International Rivers is working with partners in the region and internationally to keep the Lower Mekong River's mainstream flowing freely. 5

6 Table 2:Proposed Dams on the Mekong Mainstream [18] Project Country Approx Location Commissioning Installed capacity (MW) Height (m) Crest length (m) Active storage (million m 3 ) Max reservoir area (km 2 ) Nuozhadu CHN N E N E , Pak Beng N E N E , Luang Prabang N E N E , , Xayaburi N E N E , Pak Lay (Option 1) N E N E ,

7 Sanakham N E N E , Pakchom Lao PDR/Thailand N E N E ,079 1, Ban Koum Lao PDR/Thailand N E N E , Lat Sua N E N E , Don Sahong N E N E , Stung Treng Cambodia N E N E 2016(?) , Sambor Cambodia N E N , ,

8 4. Impact of dams development on the Mekong fisheries The impact of dams on fisheries is well researched around the globe. It has been well established that dams affect the ways in which river ecosystems and hydrology work. River damming is a process so intense and dramatic that it results in the creation of a new ecosystem. Dams affect fisheries in several significant ways: - Acting as barriers to fish migrations. Fish migrations are highly complex events and an inherent part of fish breeding cycles. The presence of dams in the Amazon Basin, for example, has halted the long distance migrations of several species of catfish, reducing downstream catches by up to 70 percent. years. - Interrupting natural flood cycles to which fish have adapted over thousands of - Hardening of the riverbed. Dams typically release water in bursts, which removes smaller sediments like silt, sand, and gravel, as well as aquatic plants and animals and debris from vegetation. As a result, the bedrock below the dam becomes exposed and loses its value as a habitat for fish. - Capturing sediment behind dam walls. Dams are highly effective at trapping sediments. Sediments are a significant source of nutrition for fish. - Altering water temperature. The water released from a dam is typically of a different (usually lower) temperature than the natural temperature regime downstream. When water is released, downstream water temperatures are rapidly altered, which has a direct impact on fish habitats and populations. Cambodia is likely to bear the brunt of fisheries decline as a result of dam development, but the loss will also be significant for riparian communities in Laos and Thailand, as well as communities in the Vietnamese Mekong Delta. Fisheries degradation will disproportionately impact the poor, but fisheries alone cannot address all development and poverty reduction needs. [33] By 2030, if the 11 proposed 8

9 mainstream dams are built, the animal protein at risk of being lost every year is equivalent to 110 percent of the current annual livestock production of Cambodia and Laos. Fish consumption is expected to rise as the regional population continues to grow and as diets continue to improve as a result of increasing development. Fish biodiversity will decrease over the next 20 years as a result of overexploitation, decreased habitat diversity and (in some locations) declining water quality In the Lower Mekong, mainstream dams will likely lead to the loss of productivity and biodiversity of migratory species that use tributary systems. If, by 2030, eleven dams are built on the Lower Mekong Basin mainstream, forecasted total fish losses would amount to 550,000 to 880,000 tonnes compared to the baseline year 2000 (a percent decrease). This is a loss of approximately 340,000 tonnes compared to a situation in 2030 without mainstream dams. Estimates of the cost of lost fish production range from US$200 million to US$476 million a year. Mainstream dams located upstream of Vientiane would have less impact on fisheries resources than those located further downstream. The impacts of mainstream dams on fisheries production varies from project to project, depending on distance from the major Mekong floodplains and position in relation to its important tributaries. Tributary dams will also have a considerable impact on fisheries production. Together, the 78 constructed or planned tributary dams of the Lower Mekong Basin would produce less energy and pose greater risk to the environment, including catastrophic impacts on fish productivity and biodiversity, than the planned upper six Lower Mekong Basin mainstream dams. The planned tributary dams that will yield the greatest impact on fisheries production are the Lower Sesan 2 in Cambodia, which will reduce basin-wide fish biomass production by 9.3 percent; the Sekong 3 Downstream in, which will reduce basin-wide fish biomass production by 2.3 percent; the Sekong 3 Upstream in, which will reduce basin-wide fish biomass production by 0.9 percent; and the 9

10 Sekong 4 in, which will reduce basin-wide fish biomass production by 0.75 percent. Dam development has been recognized as a potential catalyst for aquaculture in the region. Data on aquaculture production in the Mekong River Basin is generally poor. It is known that aquaculture production has increased in recent years, with the majority of growth occurring in the Mekong Delta A large portion of aquaculture production is, however, for export and does not therefore benefit regional diets. [20][33][38] In 2008, aquaculture production was estimated to be about 2 million tonnes, equivalent to 78 percent of wild fisheries consumption. Aquaculture in the Mekong is heavily concentrated in the Mekong Delta. As the Mekong Basin s population grows, demand for aquatic resources will increase, hence driving up prices and improving investment opportunities for aquaculture. By 2015, it is predicted that aquaculture will be able to meet the extra demand for fish products, which is expected to exceed the capacity of wild capture fisheries. By 2020, it is expected that aquaculture production will no longer be able to keep up with demand, and pressure will return to wild capture fisheries to make up the shortfall. Production is not the same as consumption. As has been well demonstrated elsewhere, the availability of large amounts of food does not necessarily equate with consumption if it is not distributed to those who need it, and the latter cannot afford to buy it. This is an important distinction between wild capture fisheries and aquaculture aquaculture production must be paid for by those who consume it; this is not necessarily the case for wild capture fisheries. Whether or not aquaculture can replace lost production from wild-capture fisheries as a result of dams is uncertain. Scenario studies suggest that it can, under bestcase scenarios. Under mid-case assumptions there will also be excess yield, except when all mainstream dams are built. In the worst-case scenarios, there would be a significant basin-wide deficit after 2015 of 436,000 tonnes per year. Most of this deficit would accrue in Cambodia. Thailand and the Vietnamese highlands would also suffer a 10

11 deficit, and in there would be a small deficit in the worst case. The Mekong delta would be in excess under any scenario due to its large aquaculture production capacity. Even if current trends to intensify aquaculture production continue, if nothing is done to mitigate and manage capture fisheries impacts, there will be a significant basinwide deficit that could not be replaced by aquaculture. These figures do not include the large quantities of aquaculture products produced in the Mekong Delta that are or will be exported out of the Lower Mekong Basin. If kept in the basin, these could compensate for any basin-wide deficit, but it is not necessarily the case that increased production will benefit poor people. Therefore, the most-affected people would also be least able to pay for such products. Aquaculture requires significant investment in addition to the technical and political support required to sustain it. and its future expansion has not been adequately assessed. Large-scale aquaculture does have significant ecological impacts, particularly through the accidental introduction of non-native species to rivers or the overharvest of fry populations from the wild used as fish feed. Small-scale aquaculture may, however, be able to contribute to increased food security in rural areas. Currently, reservoir fisheries account for approximately 10 percent of Mekong fishery production. Reservoirs will not be able to support the same levels of fish diversity as the present riverine system (ICEM, 2010; Roberts, 1996). Only nine Mekong fish species are known to breed in reservoirs (Baran 2006). In the past, reservoir stocking has not been able to compensate for the level of capture fisheries losses. Reservoirs may become eutrophic and deoxygenated as well as sites of increased outbreaks of fish disease experienced after dam construction; such cases have been reported from some Mekong dam reservoirs. It is highly unlikely that reservoir fisheries will be able to compensate for fisheries losses. 11

12 5. Some proposed solutions There are several actions that would help ensure the survival of the giant fish species of the Mekong, including: - Maintenance of connectivity between rearing grounds and spawning habitat: Many species of Mekong fish have complex life cycles that involve long-distance migrations. Maintenance of migratory pathways is crucial. - Management of the river for environmental flows: Both the fish and the fisherfolk of the Mekong rely on the natural dry season, rainy season cycle. Flows often cue fish to migrate or spawn and the high flows of the rainy season open up vast habitats for feeding fish. Likewise, local people have invented all manner of ingenious ways of catching fish and most of these methods are adapted to a specific site, flow, and time of year. - Regulation and monitoring of harvest: Over-harvest is a serious threat to the Mekong's largest, longest-lived, and most vulnerable species. In areas with heavy fishing pressure (and that includes virtually the entire Mekong Basin), catch of the largest fish must be regulated to ensure their survival. Lessons from other parts of the world indicate that relatively slow-growing large-bodied fish cannot sustain heavy fishing pressure indefinitely. - Research and decision-making based on research: This may seem like standard scientist-speak, but research on the ecology and conservation status of giant fish is urgently needed in the Mekong River Basin. The "dog-eating" catfish (Pangasius sanitwongsei) is a case in point. We know almost nothing about its ecology or conservation status and yet it is undoubtedly one of the largest, most rare, and most vulnerable fish in all of Southeast Asia. It s likely that at least a hundred times more research is being done on salmon in the Pacific Northwest of the United States than on fish in the Mekong, but the consequences of losing the Mekong s fish are a hundred times more significant in terms of biodiversity and potential impact to livelihoods. 12

13 6. Conclusion Academic researchers are attempting to redefine how villagers and governments recognize and define wealth on the Mekong. Apisom Intralawan, an ecologist at Mae Fah Luang University s Institute for the Study of Natural Resources and Environmental Management in Thailand, says official assessments that only value hydropower and industrial growth are using "a narrow definition of poverty." Communities may be "poor, but they have water security, which translates into food security, and they have social trust." A cost-benefit analysis Apisom coauthored with ecological economist Robert Costanza and others in 2011 concluded that dam-building plans have undervalued affected fisheries and underestimated impacts on wetlands and aquaculture. Instead of creating $33 billion in economic benefits, the Lower Mekong dams would cost the region up to $274 billion in degraded resources, lost ecological services, and other impacts, according to estimates by Apisom and Costanza. The full slate of potential Lower Mekong dams would produce nearly 14,700 megawatts of power, boosting Southeast Asia s energy generating capacity by 25 percent. But the dam development is proceeding over the objections of environmental activists, many community leaders, and the intergovernmental Mekong River Commission, testing the commission s authority and posing a threat to regional cooperation. A last, temporary cofferdam is scheduled for placement at Xayaburi in July 2015, marking the full blockage of the river and a point of no return. "At that point, if they allow the dam to go forward, we can expect ecological changes," says Trandem. 13