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Case Study
Thailand: Pak Mun Dam and Mekong/Mun River Basins

   Case Studies
  Country Studies:

Final Paper - Executive Summary
November 2000

The Pak Mun report is one of 8 case studies undertaken world-wide with a common methodology and approach that sought to inform the Commission on the performance and the development effectiveness of large dams.  This case study concerns the Pak Mun Hydropower project, a run-of-the-river dam located near the confluence of the Mun and the Mekong River in the Northeast region of Thailand. 

The report attempts to compare the planned intended outcomes and the actual results. The case study would provide an analysis of the performance and the manner in which decision-making processes have responded to an evolving social, economic and political context since project completion. The lessons learned from the planning and decision-making process will directly inform the Commission's findings and recommendations. Six central questions have been identified that are key to the World Commission on Dams (WCD) work programme and methodology. These questions serve to structure the information collection, discussion and assessment of the topics of performance and development effectiveness. The Pak Mun case study sought to address these questions:

  1. What were the projected vs actual benefits, costs and impacts?
  2. What were the unexpected benefits, costs and impacts?
  3. What was the distribution of costs and benefits, who gained and who lost?
  4. How were decisions made?
  5. Did the project comply with the criteria and guidelines of the day?
  6. How would this project be viewed in today's context?

The case study has primarily used existing data sources and reports to inform its assessment. Some additional research in selected areas has been undertaken. Assessing development effectiveness entails taking account of the views and perspectives of different stakeholders and project-affected groups. As an integral part of the methodology, in parallel to the study process, two consultation meetings were included. These meetings were intended to ensure that the views of different interest groups could be considered by the study team, and provided opportunities for comments and input.

The Pak Mun Project: Description

The Pak Mun Dam is built on the Mun River, 5.5km upstream from its confluence with the Mekong, in the province of Ubon Ratchathani, in Northeast Thailand. The dam is typed as roller compacted concrete with a maximum height of 17m and total length of 300. The reservoir has a surface area of 60 square km at normal high water level of 108 metres above the mean sea level (MSL) and a capacity of 225 million cubic metres. The Electricity Generating Authority of Thailand (EGAT) built and operates the dam as a run-of-the-river hydropower plant. Its operating rules are designed to ensure that the water level does not rise above 106mMSL during the dry season, from January to May and retains a maximum level of 108m MSL for the rest of the year. The storage capacity of the dam's reservoir is essentially that of the pre-existing river channel.

When the Environmental Impact Studies conducted in 1982 indicated that approximately 4 000 households would be displaced if the reservoir was impounded to a level of 113 MSL. Therefore an alternative design with a normal water level of 108 MSL was agreed upon in 1985. The relocation of the dam site significantly minimised the extent of displacement to an estimated 248 households. The original project design was further modified by relocating the dam 1.5km upstream to avoid the submergence of Kaeng Tana rapids, an important environmental and tourist site. EGAT also decided to lower the reservoir to 106 MSL during dry season from January to May and to adjust the dam's operating regime to uncover the upstream Kaeng Saphue rapids. However a new environmental impact assessment (EIA) which may have identified and anticipated some of the new environmental impacts arising from the new location was not conducted at this stage.    

What were the predicted versus actual benefits, costs, and impacts?

Cost of the project

In May 1989 the Cabinet approved the 17m high, 136 mega watt (MW) Pak Mun project with a budget of 3.88 billion Baht (US$ 155.2 million). In 1991 National Economic and Social Development Board (NESDB) approved the modified project cost of 6.6 billion Baht (US$ 264 million). The final cost tally by EGAT in 1999 was 6.507 billion Baht (US$ 260 million). In nominal terms the project costs increased by 68% from the original estimates between 1989-99. Not including taxes and interests during construction the cost overruns in nominal terms are 91% over original estimates in 1988.  However, the analysis indicates that in real terms (calculated at constant 1998 prices) the cost overun was considerably less.

Compensation and Resettlement costs increased from 231.55 million Baht (US$ 9.26 million) in EGAT's 1988 estimates to an actual expenditure of 1 113.1 million Baht (US$ 44.24 million)  till 1999. In real terms resettlement costs increased by 182%. Compensation for loss in fisheries, which was unanticipated in the original estimate, accounted for 395.6 million Baht by April 1999 (US$ 15.8 million). 

Benefits - Hydropower

Pak Mun dam is located at the end of a large watershed where rainfall and run off vary considerably between dry and wet seasons. During wet months Pak Mun can turbine the daily inflow to serve the 4 hour peak demand and in addition can generate power in off-peak hours with surplus water available. However during the dry months the plant cannot produce its full rated capacity for the 4 hour peak demand due to insufficient water.

The output of the plant depends on the water level in the reservoir and the tailwater level. The Pak Mun Dam's power production peaks in the wet season when it is least needed in the power system and is lowest in the dry season when it is most needed. When the water levels in the Mekong river are very high, the power plant will be shutdown for lack of generating head.

The operation records from the commissioning of the plant in 1994 indicate that Pak Mun's average annual output has been 290 Giga Watt per hour  (GWh). This compares with the estimated average of 280 GWh. Pak Mun dam featured as a 136 MW, run-of-the-river project, to serve peaking needs in EGAT's presentation to the Cabinet as well as World Bank documents. However following the rules based on the daily power output data betweeen 1995-99, Pak Mun plant can use only 15% of its capacity as reliable 4 hour peak capacity. The actual dependable capacity of Pak Mun project calculated from daily power output between 1995-98 assuming that all available power gets assigned to a 4 hour peak demand period is only 20.81 MW. This 21 MW is what the Pak Mun project offsets in gas turbine capacity. However the value of alternative generating capacity adopted for comparative purposes by EGAT and sanctioned by the World Bank was much higher at 150 MW.

The actual operation of Pak Mun is often different from what was assumed in the planning studies. This type of operation may be beneficial from an ancillary services point of view (such as frequency and voltage regulation, Var control etc.), but the energy benefits will be less than planned.

Recalculating the project's equalising discount rate assuming that one would need one 21 MW gas turbine to provide the dependable capacity of a 20.8 MW hydro plant, the current report reaches a value of 7.88% which is below the shadow cost of capital in Thailand.  When the benefits of the ancillary electricity net support of the dam and the green house gasses reduction benefit of the dam were included in the evaluation of the dam, these benefits were not sufficient to make the project economically justifiable.

EGAT and the World Bank indicated their disagreement with the finding. They explained that they looked at the overall power system at the planning stage. In the context of the whole system, it is possible that there would be enough (hydro) storage energy in the system to be able to cope with a dry year dry season output of Pak Mun. In the dry season, Pak Mun would be able to produce 136 MW over a number of hours, and that is enough to increase the output or start a thermal plant. It may not do that over an extended period, but that may not necessary. In that case the full 136 MW could be used for the capacity benefit.

Benefits - Irrigation

The Pak Mun project was presented for review to the NESDB in 1988 and to the Cabinet of Ministers in 1989 as a multi-purpose development project. External financing for the project was secured through the World Bank's Third Power Project in 1991, which besides hydropower and irrigation, identified fisheries as a major benefit. Irrigation benefits were not included in the economic analysis justifying the project by the World Bank in its 1991 Staff Approval Report.The irrigation benefits of a run of river project were doubtful and this was known at the time the irrigation benefits were quantified in EGAT's project document. 

Benefits - Fisheries

About 7% of the project benefits were attributed to Fisheries in EGAT's 1988 Project documents.

The 1981 EIA predicted that fish production from the reservoir would increase considerably, though some fish species may be affected by the blockage of river flows by the dam. The fish yield expected from the 60 square km Pak Mun reservoir was 100 kg/ha/year without fish stocking and 220 kg/ha/year with the fish-stocking programme. However, run-of-the-river reservoirs cannot sustain such high yields, as they do not provide the appropriate habitat for pelagic fish species. In Thailand even storage reservoirs that perform better under fish stocking programmes have a fish yield of about 19 to 38 kg/ha/year. The predicted fish yield from Pak Mun head pond was too high. A more realistic estimate would have been around 10 kg/ha/year.  There has been no evidence to indicate that the fish productivity of Pak Mun reservoir has reached anywhere near the anticipated 100 kg/ha/year. 

The 1981 EIA valued the total annual predicted fish catch in the head pond at US$ 320 000 at the rate of 20 Baht per kg, without stocking. With stocking program the predicted catch would be worth US$ 693 000 at the rate of 20 Baht per kg. The 1981 EIA underestimated the total value of fishing yields that could be obtained from the free-flowing river. After the completion of Pak Mun dam, the lower Mun River experienced a decline in fishing yields with an estimated value of US$ 1.4 million per annum at 20 Baht/kg. In addition to this the decline in fish species upstream led to the closure of 70 Tum Pla Yon traps. At the price of 18 Baht/kg at the end of 1980s, the value of annual catch from these traps is calculated at US$ 212 000 per annum (1 US$ = 38 Baht). EGAT and the World Bank  expressed their disagreement with the study team's findings. A detailed basis for the conclusion is presented in the annex related to EGAT's comments.


The 1982-83 Environmental Planning Survey predicted 241 households as displaced people. The actual number of households displaced by Pak Mun dam was 1,700. Unpredicted by the EIA, a large number of households were adversely affected due to declining fishing yields. Until March 2000, 6,202 households were compensated for loss in fisheries during the 3-year construction period. Compensation for the permanent loss of fisheries has not been given.

What were the unexpected impacts, if any?

Impact on Fish Migration & Fish diversity

Of the 265 fish species recorded in the Mun-Chi watershed before 1994, 77 species were migratory and 35 species are dependent on habitat associated with rapids.[3]  Available evidence does not indicate disappearance of any species before 1990, and nearly all species are very common ones to the region. Out of 265 species, about 10 were introduced species.

The decline has been higher in the upstream region. The latest survey recorded 96 species in the upstream region. Out of 169 species not found in the present catch, 51 species have been caught less significantly since the completion of the project. At least another 50 species of rapid dependent fish have disappeared, and many species declined significantly. Migratory and rapid dependent species were affected seriously as their migration route is blocked in the beginning of the rainy season, the head pond has inundated their spawning ground and the fish pass is not performing. Long-term studies are required to arrive at a firmer conclusion on the exact number of species that disappeared from Chi - Mun river basin after the construction of Pak Mun dam. The fish catch directly upstream of the dam has declined by 60-80% after the completion of the project.

There are divergent views on the extent that the decline in fish species could be attributed soley to the dam with the view being proposed that the reduction in fish species might have started prior to the study.

The Pak Mun case study concludes that the difference in number of species in fish surveys before and after dam construction may well be exacerbated by the cumulative impact of many different developments in the watershed. These include: water resources and hydropower development in Chi-Mun river watershed, deforestation, domestic waste water discharge, agriculture intensification and development, fisheries, industrial waste water discharge, saline soils and enforcement of water quality standards and classification. All these developments have contributed to a decline in fish species in the Mun/Chi watershed as a whole. The Pak Mun Dam cannot be blamed for the apparent disappearance of all these fish species. Cumulative impacts of all developments including the Pak Mun Dam have led to disappearance of fish species. Downstream of the Pak Mun project, one or two species of fish have completely disappeared from the catch after the dam construction.

Location of the dam on the Mun river 5.5 km upstream from its confluence with the Mekong has affected several migrating and rapid-dependent fish species. Thus, decline in and disappearance of several migrating and rapid-dependent fish species are directly attributable to the Pak Mun dam.

Performance of Fish Pass

The project provided several mitigation measures, including a fish ladder to facilitate fish migration. Provision of a fish ladder was based on very little knowledge and experience. This mitigation plan came out at the time the dam construction was almost completed; and even then this important plan was not well prepared.

The 1981 EIA did not consider the construction of a fish ladder necessary for the Pak Mun dam but recommended the feasibility study of a fish way. The plan for a fish pass came at a time when dam construction was almost completed. In effect, the fish pass was constructed after the completion of the dam at the cost of 2 million Baht (US$ 0.08 million). The fish pass has not been performing and is not allowing upstream fish migration. The project authorities have discontinued monitoring of the fish pass.

A vertical slot fish pass or a Denil fish pass instead of a pool and weir fish pass may have been more effective.

Reservoir Stocking as Mitigation

Reservoir fishery was developed by EGAT in response to claims of declining fish catch. Total cost of stocking the head pond with fresh water Prawn (Macrobrachium rosenbergi) ranged between US$ 31 920 and US$ 44 240 annually between 1995-98. The Department of Fisheries estimates the total annual revenue of fishing yield to range between 1.2 to 3.2 million Baht. However the estimated annual catch and revenue for fishermen are too high. The Department of Fisheries in their revenue estimate included the naturally occurring Macrobrachium species that can breed in fresh water. The M. rosenbergi spawns in salt water and migrates to fresh water and therefore cannot establish a population under reservoir conditions. For this reason it may well turn out that the stocking of M. Rosenbergi in Pak Mun head pond is not generating any income for the fishermen. The project has discontinued fish and prawn stocking.

Impact on Livelihood

In the post-dam period fishing communities located upstream and downstream of the dam reported 50-100% decline in fish catch and the disappearance of many fish species. The number households dependent on fisheries in the upstream region declined from 95.6% to 66.7%. Villagers who were dependent on fisheries for cash income have found no viable means of livelihood since the dam was built, despite efforts to provide training opportunities. As their food security and incomes destabilised they sought various ways to cope including out migration to urban areas in search of wage labour.

Some households had to settle in forest reserve areas or on other common property as the compensation money was insufficient to buy alternate land. The Thai economic crisis affected households that did not use the compensation money to buy productive assets. Cropping incomes have declined and there has been a reduction in livestock as people are selling both due to a shift from farm based occupations as well as reduced grazing land. 

Next to fisheries, loss of access to common property such as forest and grazing land has been among the other adverse impacts. Forests and riverbank dry season gardens were not compensated.

Since the completion of the project several committees were set up to assess the number and extent of households affected by loss of fisheries income. In all, over 6 202 fishermen demonstrated to the committee that they were engaged in fishing and their income affected following construction and operation of Pak Mun dam.

Based on the committee's findings, EGAT paid 90 000 Baht to each of the 3 955 fishermen in 1995, and it approved payment of 60 000 Baht each to another 2 200 fishermen in March 2000. Still, a large number of households located upstream of the dam are still waiting to be recognised for compensation. Unexpected costs of the project included the compensation for fisheries (488.5 million Baht had been paid up to March 2000) and investment on fish and prawn stocking programme. Till March 2000, 488.5 million Baht (US$ 19.5 million) had been paid as compensation for loss of fisheries livelihood.

While the government acknowledged the impact on fisheries and agreed to compensate eligible households at the rate of 90 000 Baht as compensation for loss of income during the three-year construction period, mitigation for the long-term loss of fisheries livelihood is under negotiation. On January 25, 1997, the villagers from Pak Mun joined the 99-day protest in Bangkok demanding fair compensations for the permanent loss of their fishing livelihood. Land and cash compensation promised by the government in April 1997 was retracted under a new political regime in 1998. From March 1999 villagers began demonstrations to be compensated by the Government and the World Bank for permanent loss of income from fisheries.

Decision Making and Conflict

Assessment of project impacts, like the assessment practices in past dam projects, remained focused on inundated areas and resettlement issues. Pak Mun project happened to be the first run-off-river type dam, with no reservoir and thus impacts due to flood and resettlement were not assumed to be as serious as those of other big dam projects in the region. Thus, fisheries impacts were overlooked. No study ever predicted that fisheries issues would become problematic, during construction or implementation though this issue was raised with the World Bank as early as October 1991 and prior to that with EGAT.

It has been realised by almost all of the stakeholders that planning, decision making, implementation and mitigation were done with inadequate base-line information, especially on fisheries, the most serious and most controversial of the issues. The project authorities considered that it was not possible to determine the number of fishermen actually affected or the extent of loss suffered and there was a perception of exaggerated and ever-increasing claims for compensation. ? The absence of a proper baseline meant that claims for compensation by a large number of families would not be considered legitimate which meant that the only possible recourse for the affected villagers was prolonged protest.

Thus, the Pak Mun project becamemired in a protracted process of conflict between the adversely-affected villagers, the project developers and the Government. Exclusion of affected people from the decision-making process gave rise toprotracted protests, demonstrations and confrontations. These actions were taken in order to seek recognition and settlement of compensation and rehabilitation entitlements. This resulted in very strong negative perception within the community for the project.

Impact on Rapids

The height of the dam was reduced and its location changed from the initial plan to drastically reduce resettlement of persons and to preserve the Kaeng Tana and Kaeng Saphue rapids that are tourist attractions. This was done at a substantial sacrifice in power benefits.  Nevertheless, more than 50 natural rapids were permanently submerged by the project. These rapids served as the habitat of a number of species of fish, and thereforeseveral rapid-dependent fish species seem to have disappeared. The implication of the loss of rapids for fisheries was not assessed in the project's environmental impact study.

Other Environmental impacts

The project has resulted in the loss of riverbank vegetation, natural forest and community forest. In the pre-project period, the women in the community harvested 40 edible plants, 10 bamboo species and 45 mushroom species for household subsistence and small income. A number of medicinal plants were also found near the Mun riverbank. Loss of these plants and vegetation through inundation has implications for biodiversity and household food security. These aspects were overlooked in the environment assessment study in 1982 and in the absence of a new EIA for the redesigned project. 

What was the distribution of costs and benefits: who gained and who lost?

Pak Mun project was a part of EGAT's least cost development plan to serve the peaking needs of Northeast Thailand. However as the project cannot function as a reliable peaking plant of 136 MW due to a number of constraints; the nature and extent of gain to Thailand's Northeast region from the power contribution of the Pak Mun project remains a matter of diverging opinion. The changing mix of technologies for generation since 1988, indicates that hydropower is gradually playing a less important role in power provision. From the data on contribution of different power generation to the seasonal peak load, it can be seen that hydropower contributes significantly during the hottest and driest months in Thailand. These are also the months when the Pak Mun hydropower plant is least able to have the water resources to contribute because it has no storage reservoir.

Communities dependent on the fisheries for livelihood in the upstream and downstream of the Mun River experienced an ongoing decline in fish catch. The Royal Thai Government had to recognise and pay compensation to 6 202 fishermen for the unanticipated loss in fisheries income. While compensation settlement has been reached with over 6 202 households regarding loss in income during the three years of construction, compensation for permanent losses in livelihood remains under negotiation. 

Despite the cash and credit compensation, permanent loss of fisheries cannot be replaced by a one-off cash compensation. As a result of the project and in the absence of baseline information, the Thai Government is left vulnerable to ever-increasing claims for compensation for the loss of fisheries livelihood.  Regarding the issue of fisheries, all stakeholders stand to lose, not only from a disrupted ecosystem but also from increased expenditure on mitigation efforts that are unlikely to mitigate the losses.

Villagers who owned some land on slightly higher elevations were able to grow some rice prior to the dam construction. Villagers who were dependent largely on fisheries for cash income, however, have found no viable means of living since the depletion of fish in the reservoir. The changes were particularly acute in paddy production.   Along the Mun River, swamps and wetland forests, are parts of the riverine ecosystem.  During the rainy seasons, these are flooding areas and places for fish to spawn.  In the past, villagers used the area along the river to find bamboo shoots, mushrooms, native plants and vegetables that they depend on for their subsistence. During the dry seasons, they also developed narrow patches of land along the riverbanks for growing vegetables.  In the upper part of the lower Mun, where banks were not steep, land along the river was developed as paddy fields. These have brought drastic changes in the way that villagers use natural resources.  As their food and income security has been destabilized, villagers have sought different ways to cope with the changing conditions. Some of them and their children began to leave their villages to look for alternative employment opportunities, such as working in construction or in factories. Compensation was not invested in productive assets. Many affected people who were given compensation used the money to build their new house or change their roof. Many also have debts, borrowing from their cooperative as well as local moneylenders. Short-term wage opportunities and one-off cash compensation cannot replace the loss of a productive resource base by the community.

After resettlement, villagers have witnessed many social and cultural problems. The new social arrangements have disrupted former social relations and changed patterns of interaction among the villagers. In the pastthe Mun river served as the stage for their social life.  The river was where villagers met, interacted, and developed social networks of exchange. The traditional communal ceremony had usually been organized on the riverbank, but now could not be held due to the submergence of the ceremonial site and, in part, due to the social disintegration of the communities. Since the beginning of the Pak Mun project conflicts of ideas and interests arose between those who opposed the dam and the kamnan and headmen group. The conflict was intensified during protests and demonstrations for compensation. Those who were opposing the dam were often discriminated against. The conflict over the dam project at the local level created mistrust and deep social rifts.

The local community and adversely-affected villagers have expended considerable time and effort over nearly ten years in protests, demonstrations and negotiations with the government and project authorities. What became an issue of lost livelihood and a conflict over compensation was initially a demand for a role in the decisionmaking processes pertaining to the development, utilisation and transformation of natural resources that form the livelihood base of the community. The process has created bitterness and negative perceptions withinthe community at being excluded from critical stages in the decision-making process.    

The World Bank and EGAT have suggested that the income level of the families in the region improved significantly since the completion of the Pak Mun project. The National Rural Development Committee (NRDC) data waspresentedas evidence. The NRDC data wasanalysed and inferences drawn (see Annex 3 for details). However, the data wasnot used in drawing conclusions. See Section 11.6; Annex 3 for an understanding on the NRDC data.

The study team finally based its conclusions on the primary data generated by the study as well as other studies conducted specifically in relation to the Pak Mun project. Thus, the 1996-97 Operations Evaluation Department of the World Bank (OED) study was also used as a benchmark.

How were the decisions made?

The National Energy Authority (NEA) initiated development of the water resources of the Chi-Mun watershed. The preliminary feasibility study completed in 1970 selected the Kaeng Tana rapids as the possible dam site. By May 1979 the project was transferred to EGAT for further feasibility studies.

Environmental Impact Studies conducted in 1982 indicated that approximately 4000 households would be displaced if the reservoir were impounded to a level of 113 MSL. In order to reduce the project's environmental and social impacts, after a new feasibility study an alternative design with a normal water level of 108 MSL was agreed upon in 1985. The relocation of the dam site significantly reduced the extent of displacement from the project to an estimated 248 households. The original project design was further modified by relocating the dam 1.5 km upstream to avoid the submergence of Kaeng Tana rapids, an important environmental and tourist site. EGAT also decided to lower the reservoir to 106 MSL during dry season from January to May and to adjust the dam's operating regime to uncover the upstream Kaeng Saphue rapids, a popular tourist destination. It should be acknowledged that EGAT and the Thai government made substantial sacrifice in power benefits in order to minimise social and environmental impacts.

However a new EIA was not conducted at this stage that may have identified and anticipated some of the new environmental impacts arising from the new location of the Pak Mun project.    

In April 1989 the project was presented by EGAT to the Council of Ministers of the Thai Government (the Cabinet).  Nearly one year later the Pak Mun Hydropower Project was presented as part of a loan package to the Board of Governors of the World Bank. In 1991 when it appeared that project costs would have to be increased, it was presented to NESDB for re-approval.  In each of these occasions costs and benefits were presented.

The Pak Mun dam was described as a multipurpose development project by EGAT in the project document dated March 1988. Claims of associated and attributable benefits from the project, which were modest relative to the value assigned to electricity generation, included irrigation, fishery, navigation improvement and recreation enhancement. Only the benefits of power, irrigation, and fishery were quantified in EGAT's project document. The project later qualified for World Bank loan financing as part of Thailand's Third Power System Development Project. The World Bank's Staff Appraisal Report (SAR) was completed in July 1991; the Bank's Board of Directors approved the project in December 1991.

In August 1991 when EGAT resubmitted the project to the NESDB for the endorsement of a 70% increase in estimated investment costs, along with the expected annual energy output, the irrigation and fishery benefits remained unchanged. The revisions showed that the Pak Mun dam as a multipurpose development project including resultant irrigation and fishery potentials was still worthwhile. NESDB accepted the project as proposed and endorsed EGAT's revisions. The project's Economic Internal Rate of Return (EIRR) changed from 18.71% in 1988 to 17.35% in 1991- irrigation benefits were quantified. Neither the SAR nor the revised NESDB application in 1991 identified how the irrigation components were going to be financed but benefits were included in both and quantified in the latter's presentation.

In a recent communication with the Pak Mun study team EGAT has indicated that the power benefit of the Pak Mun Dam is the core benefit of the project. Other benefits such as fishery, irrigation, etc. are secondary, and were not necessary for project justification.

The conceptual economic benefit of avoided costs for power generation from the next best alternative, was used in the project's economic evaluation (the power only component). The actual hydropower benefits of the dam were not used by EGAT or the World Bank in the economic justification of the project. Both institutions limited their analysis to a switching value analysis, also called Equalising Discount Rate analysis. Such an analysis is used to rank projects by priority once they have been estimated to be economically viable. The lack of proper ex-ante economic analysis means that it is not possible to conduct a comparison of Projected and Actual Economic Value of the project.

The Cabinet mandated EGAT to establish eligibility criteria and finalise the process of compensation to the affected people. The Governor of the Province of Ubon Ratchathani, the Director-General of the Department of Fisheries, and the Permanent Secretary of the Prime Minister's Office were put in charge of the compensation process. The focus of the process shifted from lost assets like land and other properties to decline in fisheries affecting livelihood.

Affected villagers were not consulted at the early stages of the decision-making process and there were no attempts to include them in the decision making on the project or the mitigation measures. The issues around inadequate assessment of impacts and compensation were not addressed at the outset. Negotiation on compensation began only after long protests by the affected community and NGOs. Participation of affected villagers and NGOs in the compensation process was first elicited through the Committee for Assistance and Occupational Development of Fish Farmers (CAODFF), formed by order of the Prime Minister in January 1995, eight months after completion of the dam. The Director-General of the Department of Fisheries headed the committee. EGAT remained solely responsible for all costs relating to the works of the various committees and working groups and for the compensations paid out.

Did the project comply with the criteria and guidelines of the day?

The Pak Mun project complied with the standards of the Cabinet at the time and was thus approved in May 1990.

Under the 1992 Promotion and Conservation of National Environment Act, reservoirs with capacities larger than 100 Million cubic meters (MCM) or surface areas greater than 15 square km require an Environment Impact Assessment Study. The EIA studies have to be submitted to the Office of Environmental Policy and Planning for consideration prior to being submitted to the Cabinet or appropriate authorities for endorsement for permission to proceed.  Pak Mun dam with a reservoir storage capacity of 225 MCM and surface area of 60 square km would require an environmental impact study under the 1992 law. Since the Cabinet endorsed the project in May 1990, the provisions under this act did not impinge on Pak Mun dam.

The 1981 EIA produced inadequate baseline information. Baseline studies of aquatic resources need to cover the different seasons and a timeframe of at least 2 years. Assessment of natural fluctuations in abundance of fish populations as well as the cumulative impacts on aquatic resources from other development projects in the watershed was necessary. An appropriate socio-economic survey was required to identify the extent of dependency of the local population on fisheries. Further, the project that was approved by the Cabinet was different from the one for which the original EIA was conducted in 1981.

By the time the project reached implementation stage, the nature, extent and site of the project had changed and this warranted a new EIA. By 1990, the Pollution Control Department and the Office of Environmental Policy and Planning of the Ministry of Science, Technology and the Environment had also evolved an extensive set of guidelines, standards, classifications and procedures in place to carry out appropriate EIA. The World Bank too had an extensive set of procedures and guidelines in place for the Terms of Reference, implementation and review of EIA. The Pak Mun dam did not comply with the existing World Bank guidelines that required a new EIA and appropriate impact mitigation prior to the implementation of the redesigned project. If the Pak Mun project had complied with the World Bank's standards at the time of appraisal in 1990, many of the serious unexpected impacts could have been anticipated and avoided. By the time mitigation measures related to fisheries were put in place in response to people's protests, the dam construction work was completed.

Compensatory measures apart from inundated houses and land were formulated and implemented at a later stage of the process. The monitoring of fish species and fisheries activities after the completion of the dam has been haphazard and not systematic. The performance of the fish ladder has not been adequately evaluated, and monitoring withdrawn. Adaptive management such as relocation and improvement of the fish ladder might have helped, but have not been considered.

The process of compensation of affected fisheries households has been a long and tedious process as a result of inadequate baseline studies that should have systematically defined the number and location of households depending on fisheries and also the value of their fish catch.

How would this project be viewed in today's context?

The economic premise on which the project was justified can be questioned. The planners confused a switching value analysis, also called Equalising Discount Rate analysis, with a traditional economic benefit analysis. The former analysis should be performed to choose the best of two project implementation solutions that have already proven to be both economically viable.  When applied to power projects the switching value analysis should be done on projects that have the same dependable capacity and this was not done in case of Pak Mun project.

Since the Pak Mun project was in reality conceived and operated as part of EGAT's power development plan to respond to long-term national load forecasts, its claim as a multipurpose project is misleading. 

In the present context, the absence of assessment and lack of consideration of the project impact on fish and fisheries in Mun River in the initial planning and decision-making stages would be considered a critical lapse. This is more so given the fact that this World Bank funded project was approved and implemented in the early 1990s. The absence of comprehensive assessment of the households whose fishing occupation, fishing income, and subsistence was affected by the dam at appraisal meant considerable unplanned cost escalation in terms of compensation. The participation of affected communities and civil society was elicited late in the process of compensation and mitigation. Confusion resulted from lack of clear division of institutional responsibility and this was compounded by lack of clarity in eligibility criteria as a result of which affected people spent nearly ten years in negotiating compensation claims with the government.

With hindsight, as required by the World Bank guidelines, a fresh EIA for the redesigned project would have been called for whose terms of reference should have included nature and extent of impact of the project on livelihoods based on fisheries. Such a study would have been useful in making available relevant baseline for comprehensive identification of fishing villages, the extent of population affected, the level of dependency on fisheries by season, the prevailing income, and the resettlement location options allowing continued access to the riverine resources and alternatives.

If plans and policies were adequately implemented with respect to social impacts and resolution of conflicts, villagers would not have had to waste time and effort in negotiating and protesting against the dam.  Nor would the country as a whole have lost an important ecosystem.

One of the key conclusions emerging from the study is that if all the benefits and costs were adequately assessed, the study team believe it is unlikely that the project would have been built in the current context.

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