Dr To Van Truong a, Tarek Ketelsen b

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WATER RESOURCES IN THE MEKONG DELTA: A HISTORY OF MANAGEMENT, A FUTURE OF CHANGE Dr To Van Truong a, Tarek Ketelsen b Introduction The Mekong Delta is characterized by change, which occur over a wide range of spatial and temporal scales. In the past the delta lay submerged below the sea and today it continues to accumulate sediments from as far away as the Himalayas so that the delta is constantly changing and reclaiming land from the sea. In fact, because of the delta s dependence on a combination of ecosystem functions including tides, rainfall, and erosion that operate over a short timeframe, it is highly susceptible to human and environmental change. Now the Mekong Delta, a fringing ecosystem between terrestrial and marine environments, is facing perhaps the most devastating change of all, unique because Climate Change is bringing changes at a rate unprecedented in recent history. Whereas in the past change was a comparatively slow phenomenon with patterns set in motion over thousands of years, current changes require a sense of urgency as significant changes to the hydrologic regime are occurring over decades and even years requiring water management initiatives that are flexible and capable of evolving and adapting close to the speed at which climate change is occurring. Change has therefore become an issue because of the accelerated scale at which it is operating in both biophysical and socio-economic environments. Regardless of what mitigation efforts are taken internationally, climate change impacts for the next 40 years are inevitable (IPCC, 2007). After 2050, the impacts of climate change will largely depend on how we, as an international community, respond today, but changes to sea levels, rainfall regimes and storm frequencies before 2050 are determined by current levels of CO 2 in the atmosphere. This means that for the vulnerable communities in the world, adaptation is the most urgent issue. Furthermore, most impacts of climate change will be transferred to human and ecological communities via the hydrologic cycle, for example, through sea level rise, storms, flooding, and droughts. This places water resource management (WRM) at the front lines of human adaptation to climate change. A recent study by the World Bank (2007) identified Viet Nam as the most vulnerable nation in the developing world in terms of population, GDP, urban extent and wetlands, and the second most vulnerable in terms of percentage of total area affected. The Mekong Delta is one of the most vulnerable regions of Viet Nam. Therefore, planners and engineers working within the delta, face some of the most a Lead author and Director of the Southern Institute for Water Resource Planning, 271/3 An Duong Vuong Street, District.5, Ho Chi Minh City Viet Nam b AYAD (Australian Youth Ambassador for Development) Water Resource Researcher at the Southern Institute for Water Resource Planning 1 Deleted: Q

daunting and challenging problems of WRM in the world. The success of their response to this challenge will not only impact the livelihood of some 18 million local inhabitants and the national economic growth of one of South-East Asia s development success stories, it will also serve as an example for other vulnerable nations. This places Viet Nam in a unique position, as a nation with strong technical capacity; it has the potential to become one of the world leaders in climate change adaptation. This chapter is divided into four parts. Section 1 provides an historic outline of water resources and management in the Mekong River basin and the delta in particular. It tracks the introduction of Integrated Water Resource Management (IWRM) and Participatory Irrigation Management (PIM) into the management superstructure, the rise of the Mekong River Commission (MRC) and the initiatives of the Vietnamese government in providing for the socioeconomic development of the region and the preservation of vital ecosystem functioning in one of the most important and diverse river systems in South East Asia, if not the world. Section 2 then tracks the current debate and consensus on climate change (CC), culminating with a review of the latest findings by the Intergovernmental Panel on Climate Change (IPCC). Based on experiences of managing water-related extremes in the delta, the chapter then qualifies what the regional and local impacts of CC will mean to the current regime of water management in the delta. Section 3 continues by exploring the particular vulnerabilities of the delta community, the future directions of water resource management, and the important interaction between disaster preparedness and every day IWRM. In particular, this section discusses how these two fields, often considered mutually exclusive, are being brought closer together in a warming climate. The final section explores the relationship between national and international stakeholders and how these partnerships themselves need to adapt to CC, if the local communities are to successfully adapt to the rapid changes in our global climate. It also provides some recommendations to direct future efforts and improve the effectiveness of IWRM in the Mekong Delta. 1. Water Resources in the Cuu Long Delta (CLD) 1.1 Water Resources in the Lower Mekong River Basin (LMRB) The Mekong River is one of Asia s great rivers: it is 4,200km long with a catchment area of 795,000km² (KOICA, 2000). It flows through six countries (China, Myanmar, Thailand, Laos, Cambodia and Viet Nam), incorporates a massive lake system (Tonle Sap Lake) and downstream of Phnom Penh fans out into a series of channels, before discharging into the South China Sea. Due to geophysical and political differences, the Mekong River Basin is divided into two sub-catchments; the Upper Mekong River Basin, including China and 2

Myanmar, and the Lower Mekong River Basin (LMRB), considered as the area downstream of Laos and Thailand. The LMRB constitutes 77% of the total catchment area. Biodiversity and basin health Starting in the Tibetan plateau the river forms a wide variety of habitats, before ending in the sub-humid floodplains of the Mekong Delta. It is the size of the basin, the wide variety of ecosystems it supports and the minimal regulation of its flow, which contributes to its high levels of biodiversity and productivity. After the Amazon, the Mekong River basin is considered to have one of the highest levels of biodiversity on earth, including 1,200-1,700 species of fish (MRC, 2003; ARCBC, 2009). The LMRB is also home to some 60 million people, most of whom are agrarian farmers and fishermen and therefore dependent on the ecosystem services of the LMRB for survival. For instance, 90% of Cambodians rely on the fish for their protein intake, while Vietnamese fishermen harvest 400,000 tons of fish annually (Cornford et al, 2002; MRC, 2003; ARCBC, 2009). Most of the historic land clearing has been for agricultural purposes, most extensively in Vietnam and Thailand, while Laos and Cambodia contain the majority of the remaining forest systems and deforestation rates of 2-3% of the remnant forest cover (White, 2002). Climate & rainfall regime The LMRB has two seasons, the rainy and dry seasons. In mountainous regions of the catchment, rainfall is driven by changes in surface elevation, while the lower reaches of the basin typically experience rainfall in the afternoon/evening due to convective falls (White, 2002). Rainfall rates are highest in north-eastern Laos (3,500 mm/yr) and lowest in northeastern Thailand (1,000 mm/yr) (White, 2002). Relative humidity exhibits a similar broad range across the LMRB (50-98%), while evaporation rates show smaller variation (1,500-1,800 mm/yr) (White, 2002). River morphology & flow The Upper catchment of the Mekong Basin is rugged, forested and mountainous, especially in China and Laos. It is characterized by steep gorges, narrow river channels and fast flows. Ground cover and surface gradients result in a high sediment content of run-off and river flows, which are transported downstream. As the river approaches Cambodia, the terrain flattens and the river slows and widens. The Mekong Delta starts south of Kratie (Cambodia). Tonle Sap Lake is one of the dominant hydrological features of the Mekong Delta. The lake is a unique system which regulates flows in the Mekong River by storing water in the wet season and releasing it in the dry season, providing the base dry season environmental flows and preserving the year-round integrity of biodiversity and productivity. In total, the annual discharge from the Mekong is about 450 billion cubic metres (4.5% generated within the Mekong Delta), with an average annual discharge of 13,700m 3 /s (Phuong, 3

2007; KOICA, 2000). During the wet season, the average discharge can peak at 25,400 m 3 /s, which results in widespread flooding as the river breaches its banks (Phuong, 2007). In general flood volumes are greater in the Mekong Delta, but more disastrous in the steeply sloped upstream sections of the catchment where areas water levels can reach up to 10 m. The Mekong Delta generally sees water levels of 4 m or less (Phuong, 2007). During the dry season flows in the upper catchment drop significantly and the flows in the Mekong Delta are sustained by drainage waters from the Tonle Sap system. Sediment dynamics and erosion are one of the key ecosystem functions of the LMRB, connecting sub-catchments thousands of kilometres apart. It is estimated that 150million tons of sediment is transported down the main channel into the Mekong Delta, where 138 million tons continues down the Mekong River towards the ocean, while 12million tons flows through the Mekong s subsidiary channel (the Bassac River) entering the ocean. Figure 1. The Lower Mekong River Basin The energy potential One of the contributing factors to the regions biodiversity is the large amount of energy latent in the natural system. Changes in discharges, flow velocities and water levels are the fundamental drivers of the key ecosystem functions (flood pulse, the swelling of Tonle Sap Lake and the erosion/sedimentation processes), which in turn, create and support a diverse array of habitats and life. The river s hydraulic potential is also essential for the agricultural and aquaculture activities of local communities who rely on the transfer of nutrients, sediments and freshwater driven by the basins ecosystem functions (ICEM, 2003). Interactions with non-mrc member states are a growing issue for water resource management, especially as development initiatives, such as hydropower escalate and the scale of anthropogenic influences on the rivers hydrology increase. The total hydropower potential of the Mekong River Basin is 54,234 MW (Nguyen et al, 2004). Currently there are 16 dams in the Mekong River Basin, 14 in the LMRB and 2 in China. There are plans for significant expansion of hydropower developments in the basin, and this is likely to generate complex conflict and cooperation linkages between riparian countries (Kummu et al (eds), 2008). China plans to 4 Formatted: Font: (Default) Arial Formatted: Font: (Default) Arial Deleted: In total, the annual discharge from the Mekong is about 450 billion cubic metres (4.5% generated within the Mekong Delta), with an average annual discharge of 13,700m 3 /s (Phuong, 2007; KOICA, 2000). During the wet season, the average discharge can peak at 25,400 m 3 /s, which results in widespread flooding as the river breaches its banks (Phuong, 2007). In general, flood volumes are greater in the Mekong Delta, but more disastrous in the steeply sloped upstream sections of the catchment where water levels can reach up to 10m. The Mekong Delta generally sees water levels of 4m or less (Phuong, 2007). During the dry season flows in the upper catchment drop significantly and the flows in the Mekong Delta are sustained by drainage waters from the Tonle Sap system. Figure 1. The Lower Mekong River Basin Sediment dynamics and erosion are one of the key ecosystem functions of the LMRB, connecting subcatchments thousands of kilometres apart. It is estimated that 150 million tons of sediment is transported down the main channel into the Mekong Delta, where 138 million tons continues down the Mekong River towards the ocean, while 12 million tons flows through the Mekong s subsidiary channel (the Bassac River) entering the ocean less than 50km to the south of the Mekong. A large portion of this sediment washes out to sea where tidal and ocean currents transfer the sediments south-east along the coast to the Ca Mau Peninsula. Competing tidal and current interactions cause the sediment to be deposited on the peninsula fringe, which continues to expand by up to 50m a year in some parts. The depths of sediment layers in the delta vary between 20m in the inland areas to up to 500m at river mouths, supporting the hypothesis that most sediment is flushed out to sea before it re-enters the terrestrial environment some 150km to the south east.

export a large proportion of the generated power, and Thailand, Laos and Viet Nam have all initiated plans for increased energy trade with China, while Thailand is also making plans with Myanmar and Cambodia, and Laos is undertaking similar efforts with Viet Nam and Cambodia (Kummu et al (eds), 2008). The environmental and social impacts of hydropower on downstream regions, as well as rising energy demands, are some of the key issues facing the Mekong Basin, and all riparian nations have a vested interest in both the positive and negative impacts of this energy source. Figure 2. Hydropower potential of the Mekong River Basin (%) (adapted from: White, 2002) Additionally, the nature of the impacts that the Chinese dams will have is not fully understood. A recent study on China s existing Manwan Dam found that the infilling of the dam in 1992 caused record low water levels in various reaches of the Mekong River (Kummu et al (eds), 2008). A seasonal analysis comparing data from before (1962 1991) and after (1992 2003) construction of the dam, revealed that while water levels and discharges were significantly lower during the dry season, during the wet season they increased slightly. Furthermore, there was no significant variation in the monthly means before and after the dam was built (Kummu et al (eds), 2008). The inter-seasonal variability is likely to be further amplified by the effects of climate change (see Section 3). Without question low flows are likely to be reduced further as the demand for water increases in all the riparian countries of the Mekong, however downstream countries need to investigate thoroughly the interaction between their demand for imported Chinese hydropower and the water requirements of other sectors. Hydropower dams could either reduce or exacerbate the inter-seasonal variability in flow depending on the operational regime implemented. It should also be noted that discharge volumes are just one issue of many for a river basin with increasing hydropower development. Other issues such as sediment transport, migration of fish species, bank erosion, water quality and land clearing must also be considered when assessing the impacts of developing hydropower potential. Deleted:. 5

1.2 Water Resources in the Cuu Long Delta (CLD) The Cuu Long Delta (CLD) is the extent of the Mekong Delta within Viet Nam. It covers some 13 provinces and cities, with a total area of 3.9 million hectares and a population of approximately 17.5 million people (Phuong, 2007). The topography of the CLD is low-lying with gentle slopes, and an average elevation of approximately 0.7 1.2m above mean sea level. In general, sedimentation processes have built up the banks of the main river channels in the CLD forming a geographic hollow in the inland areas. These hollows form closed floodplains which store water after the wet season and support wetland and rice-farming systems. The socioeconomic development of the Mekong Delta, exacerbates stress on natural systems, particularly through agricultural development and living conditions of farmers. Tran, 2004) Regulation of the Greate Lake Flooding & Inundation Acid sulfate soils Upstream flows into the Mekong Delta CAMPUCHIA VIET NAM Tides Strong winds Salt water Salinity &Drought Erosion & Sedementaion Forest Fires Rainfall in the Mekong Delta Objectives for sustainable development: Production Agriculture- Forestry-Fishery; Stable resettlemnt; Infrastructure development; Environment protection. Selection of of land land and and water development development scenarios Figure 3. Major impacts and development directions of the CLD (adapted from NN. The major constraints of the natural conditions include (a) flooding over an area of about 1.4-1.9 million ha in the upper area of the Delta; (b) salinity intrusion (greater than 4g/l) over an area of about 1.2-1.6 million ha in the coastal areas; (c) acid sulphate soils and the spread of acidic water over an area of about 1.0 million ha in the lowland areas; (d) shortage of fresh water for production and domestic uses over an area of about 2.1 million ha in areas far from rivers, and close to the coastline; and (e) the impacts of global climate change to the flow regime in the upstream areas, rainfall, and climate in the Mekong Delta and threat from sea level rise from the sea. Deleted: 6

Global climate change and its subsequent effects on ecosystems, flooding, drought, riverbank erosion, water pollution, salinity intrusion, animal and human disease are becoming more and more difficult to forecast, as well as seriously affecting the production and living conditions of local people. Therefore, in order to further sustainable socio-economic development including hunger eradication, and poverty alleviation, there is a need to direct the Mekong Delta towards a general vision of effective management of natural disasters; wise use of natural resources for a prosperous and stable economy, and diversification and sustainable environment in the Mekong Delta" Climate & rainfall regime The CLD is under a semi-equatorial monsoon climate with rainfall distributed between two seasons: the dry season (November to April) and the wet season (May to November). The average annual rainfall is 1,600mm with 90% concentrated during the wet season. There is minimal seasonal variation in the average annual temperature, which remains about 26 o C throughout the year. Typhoons and storms are irregular events for the CLD under existing climate conditions. Generally low-pressure systems originating in the Pacific Ocean sweep west through the Philippines and past northern and central Viet Nam, however, occasionally some of these storms track further south crossing the CLD. In recent times major storm events have occurred and these events are likely to become more common for the CLD under a warming climate. River morphology & flow Flow in the Mekong is distributed between two seasons. During the wet season, it is driven by runoff in the upstream catchment, in particular the rugged Laos subcatchments. In the CLD water levels rise slowly and peak at 4.0m in September/October, flooding ~1.2 1.9 million ha for 2-5 months (Phuong, 2007). The Tonle Sap Lake is a natural regulatory system for dry season water levels, and is connected to the Mekong by the Tonle Sap River which joins the Mekong mainstream at Phnom Penh. During the wet season, the high water levels in the Mekong main channel transfer water into the Lake, quadrupling its size. Then, as the channel water level drops with the onset of the dry season, the system s hydraulic potential reverses the direction of flow in the Tonle Sap river, and the lake drains back into the Mekong Delta with an average downstream discharge of 3,000m³/s and an annual low flow of approximately 2,500 m 3 /sec. During the dry season, salt water intrudes into half of the CLD, and up to 50km up the main channel (Phuong, 2007). Deleted: (NEED A REFERENCE). After Phnom Penh, the Mekong River fans out into a series of channels, with the Hau (Bassac) and Tien (Mekong) rivers being the two main branches. The distribution of discharge between these channels is important to the hydrologic regime in the upper reaches of the CLD. On average 83% flows through the Tien River (increasing up to 86% in the wet season and dropping to 80% in the dry season), which then forces lateral flow and flooding in the area 7

between the two channels, such that, after the confluence with the Vam Nao River, the proportions of discharges between the two channels becomes approximately equal to each other (51%/49%) (Phuong, 2007). This redistribution of flow between the two main river channels has been enhanced by an irrigation canal network and is one of the reasons why the intra-channel riparian zone is some of the most productive land in the entire CLD. The Mekong river channel reaches a maximum non-flooded width of 1.2km at the Vam Nao confluence (White, 2002). Due to the low-lying topography and the fluctuations in the river s flow regime, the CLD is affected by two distinct tidal regimes: the semi-diurnal tide in the South China Sea (max amplitude of 2.5 3.0m); and the mixed tide in the Gulf of Thailand (max amplitude 0.4 1.2m). During the dry season, the tides drive saline intrusion deep in land, while high tides during the wet season hinder the discharge of floodwaters in upstream areas, exacerbating inundation times and depths. Based on these hydrological factors, water resources are managed by dividing the CLD into three distinct areas (Table 1). Table 1. Hydrological Zones of the CLD (adapted from: Phuong, 2007) ZONE TYPE DESCRIPTION ZONE A Flood Zone Northern part of the CLD, ~300,000 ha including An Giang and Dong Thap ZONE B Flood and Tidal mixed zone ~ 1.6 million ha bounded by the Cai Lon River, Xeo Chit rivulet, Lai Hieu Canal, Mang Thit-ben Tre rivers and Cho Gao Canal ZONE C Tidal zone ~ 2.0 million ha along coastal areas, especially adjacent to the South China Sea The flood pulse The flood pulse is perhaps the most important process in the ecology of the floodplains, and the main reason for the delta s high productivity. It facilitates the transfer of water to dry land and plant matter to the water, the latter provides energy and nutrients for the aquatic biota, while both facilitate biomass transportation (Phuong, 2007; Kummu et al (eds), 2008). The flood pulse is characterized by its timing, duration, amplitude, spatial extent, continuity, number of peaks and rate of inundation and subsidence (Kummu et al (eds), 2008). Most of these characteristics are vulnerable to changes in the flow of the Mekong River. In the future, flow in the CLD is likely to be affected by the dramatic escalation in upstream hydropower dams, conflict in water sharing based on increased agricultural activity in newly developing countries such as Cambodia, increased run-off in the mountainous catchments of China and Laos due to deforestation and other land-clearing practices, and also climate change. Furthermore, there will also be feedback between these impacts, for example climate change and hydrodams will increase inter-seasonal variability, or the dams could stagger their releases to synchronize with the dry season and thus curb reductions in the low flow of the Mekong River. 8

Human communities and their influence Deleted: Over hundreds of years, farmers have built up a complex system of irrigation and drainage works in the CLD to support agricultural activity. To this day, fishing and farming remain the key economic activities in the Mekong Basin, making water resource management one the most important management issues. Rice crops dominate agriculture in the LMRB, with up to three crops a year in highly developed areas and just one rain-fed crop in less developed regions. However, other crops include maize, vegetables, mung beans, soya beans, sugar cane, fruit trees and coconuts (Phuong, 2007). Aquaculture and fisheries in the LMRB are two of the oldest and most important sectors. Inland areas are dominated by fishing, especially in the Tonle Sap system, while coastal areas utilize estuarine environments to support shrimp farming. Of the 17.5 million people in the CLD, nearly 80% live in rural areas (Phuong, 2007). Population density is strongly correlated to proximity to fresh water sources, highest densities occur along the Hau and Tien rivers (i.e. Zone A and B), while areas of Zone C (Ca Mau, Bac Lieu and Kien Giang) have some of the lowest population densities. Farm land per capita follows a reverse pattern, along and between the Hau and Tien rivers the average farmer has 0.1 0.2ha, increasing to 1ha per farmer in more remote areas (Phuong, 2007). The economic basis of the CLD remains in the sectors of agriculture and aquaculture (generating 70%-90% of the income), however recent years have seen the diversification of the local economy, especially with the growth of the industrial and manufacturing sectors. Average income percapita is estimated at 400 470USD, however distribution is uneven, with 20 30% of the population living in poverty (Phuong, 2007). Most of the existing irrigation works in the CLD were built during the 1960s, and 1970s. In 2002, the system supplied water to only 50-60% of the design command area (Molle, 2005). The Government of Vietnam, recognizing the massive outlay required for infrastructure works, estimates that USD $750 million is required for repairs and improvements to the existing system (Oxfam, 2008). It should also be noted that currently, sediment deposition is not transferred to the floodplains concentrating in the bottom of river channels and canals, due to inefficiencies in the water distribution network. Development plans, especially in the deltaic areas of Cambodia and Viet Nam, aim to increase food production through a combination of expanding crop areas, intensifying production and improving yields (KOICA, 2000). In Viet Nam, development plans also include expansion of aquacultural production, enlargement and specialization of fruit tree growing areas and the controlled expansion of industrial and shipping activities. The main issues facing agricultural communities in the LMRB are; acid sulphate and saline soils, flooding, drought, freshwater shortages, storm events, sedimentation, bank erosion, and saline intrusion. 9

Wetlands There remain several key wetland areas of high regional significance. These include Dong Thap Muoi, Mekong River Estuary, Minh Hai melaleuca forest, Bac Lieu coastal marshes, Dam Doi bird colony, Cai Nuoc bird colony and Nam Can mangrove forest (ARCBC, 2009). Six reserves have consequently been established protecting some 20,671 ha of the total 290,000 ha of remnant wetlands (ARCBC, 2009). The support and expansion of these areas is crucial for survival of the deltaic flora and fauna, and efforts to establish the Tram Chin Nature Reserve in the 1980s have already seen the return of the Sarus Crane, once thought to be near extinction (Pacovsky, 2001). Water quality Currently, the high volumes of flows in the Mekong system possess very efficient flushing properties; consequently there are no significant problems with water quality in the CLD. However, the continued intensification of agricultural activity will see continued growth in use of pesticides and fertilizers, new industrial developments are likely to increase the pollutant loading of the delta s waterways and population growth will increase domestic waste loads, the combination of which may pose serious risks to water quality. Water quality will also be affected by the timing of river flows. Changes to the flood pulse and inter-seasonal variability could increase wet season erosion, while increased water scarcity in the dry season could result in concentrated contaminant pulses (DWR, 2008). 1.3 Water-related extremes & management issues According to the Asian Disaster Reduction Centre (ADRC), the main natural disasters facing Viet Nam include windstorms, floods, epidemics, droughts, insect infestation, landslides, wildfires, with floods droughts and windstorms affecting the most people in recent years (ADRC, 2006). Floods, other high rainfall storm events and droughts dominate water-related extremes in the CLD. Water management issues are determined by the season, during the wet season the main problems are flooding, erosion and the leaching of acidic soils, while drought, fresh water shortages and saline intrusion are the main issues for dry season water management. Flooding The main factors influencing flooding are; topography, upstream precipitation, regime flow and run-off, regulation of Tonle Sap Lake, the two tidal regimes, local rainfall and the existing infrastructure system. All of these factors undergo continual changes between seasons and even between days, resulting in a complex flood signature in the CLD, forcing communities to develop a high level of resourcefulness and adaptability in order to prosper, even without climate change. 10

Flooding in the CLD occurs from June to December with a one-month lag on upstream floods. Floods travel at 1.5-2.0 km/hr between Phnom Penh and Tan Chau, though they can be slowed if their arrival is synchronized with high tides. On average, flood waters rise and fall by 5-7 cm/day, with observed maximum rates of up to 12 cm/day during big or early floods (Phuong, 2007). The flood hydrograph usually displays 2 peaks, the lead peak generally occurs in late August, followed by the dominant peak in the middle of September/beginning of October, although in rare circumstances the two peaks can be separated by up to 54days (Phuong, 2007). Typically, 38,000m 3 /s enters the CLD during normal flood seasons, peaking at 43,000m 3 /s during extreme floods (Phuong, 2007). Approximately 82-86% of floodwaters enter via the two main river channels, while the remainder crosses the Cambodian border as overland flow. It is this overland flow which dominates flooding in Zone A due to local geomorphology and topographical features (Phuong, 2007). For water management purposes, floods are divided into three categories, based on the water levels measured at upstream gauging stations (figure 3). The similar probabilities of average and big floods give an indication of the high level of variability in the flooding regime. Figure 4. CLD FLOODING: (left) Categories based on river stage recordings & probability of occurrence; (right) typical area of annual flooding in the Mekong Delta (adapted from: Phuong, 2007; Nguyen, 2009) Deleted: 3 The widespread irrigation and drainage works used to make the CLD more productive have had some effects on the inundation regime. Specifically, in deep inundation areas they have changed the direction and water level in the fields at the beginning of the flood season, and altered the signature of the main flood in shallow inundation areas. 11

One of the key changes in WRM in the CLD is the acknowledgement that communities must live with floods, and that flooding brings both negative and positive effects to the delta (MARD, 2003). The negative impacts are well known (Table 2), however flooding also leaches the soils of acid, controls harmful insects and fish populations and deposits a huge volume of sediment. Table 2. Estimated damage from big floods in the CLD (adapted from: Phuong, 2007) Deleted: Page Break CLD Unit 1994 1996 2000 2001 2002 1. Estimated total VN Dong (Billions) 2,295.6 2,182.3 4,597.3 1,456.0 456.8 2.Agricultural production VN Dong (Billions) 1,326.4 1,036.0 948.5 372.5 216.1 - Rice reduced productivity Ha 83,981 92,984 198,328 33,036 15,777 - Rice Completely loss Ha 53,994 30,869 57,714 8,955 365 - Orchard seriously damaged Ha 12,145 1,161 4,613 4,985 1,049 - Industrial plant and upland crops Ha 55,497 76,396 63,560 32,785 32,142 Drought The other major extreme of the climate regime, is drought. Drought is often underrepresented in discussions about disasters in the CLD, because this is normally a region associated with an abundance of water and the problems associated with this excess, furthermore droughts usually operate over a much more subtle time frame than flooding and can last several years compared to a matter of months or days for storms and flooding. The most recent drought of significance for the CLD occurred in 2004 (Oxfam, 2006). According to community surveys undertaken by Oxfam (2006), not knowing what to do in droughts and insufficient water storage capacity were considered to be major limitations in drought-risk management. Predictions suggest that climate change will increase the inter-annual variability in weather patterns, increasing rainfall in the wet season, decreasing rainfall in the dry season, shifting the timing of the flood season and prolonging the duration of drought spells (Oxfam, 2006). The study found that despite progress in development works, communities in some provinces believe they are becoming more vulnerable to natural disasters such as droughts and floods, which are either the result of increasing vulnerabilities despite development initiatives or those development initiatives have failed to instill confidence amongst communities. Both of these are serious, but they will require different methods of resolution. In response to the former, the main issue is lack of sufficient knowledge, experience and financial capacity to undertake adaptation works, while failure to instill confidence in communities about development initiatives is largely due to issues of knowledge and technology transfer as well as human resource management and insufficient community participation (Table 3). Communities were often aware of long-term drought mitigation programs, however, they often felt no ownership or responsibility for them (Oxfam, 2006). Instead, communities primarily responded first, by preserving food and seed. NGOs typically responded by providing waterstorage facilities, supplying food grains and disaster training (Oxfam, 2006). Local government 12

responses included provision of food grain, building and maintaining community wells and establishing volunteer community water supply teams, while the central government provided food and financial assistance (Oxfam, 2006). Table 3. Limitations of current drought management initiatives (adapted from: Oxfam, 2006; Phuong, 2007) Increasing Vulnerability Lack of Confidence in Development Initiatives Insufficient importance given to drought management, Lack of provincial/district and communal droughtmanagement boards, Absence of policies for agricultural assistance, and poor participation of appropriate authorities in decision making and development planning, Lack of long-term drought preparedness programs, Conflict between socio-economic sectors, Overlap in authority and decision making powers in administrative management, Lack of regulations for water exploitation, Insufficient irrigation management and poor community participation in long-term drought mitigation programs, Lack of drought resistant crops and animal breeds, Lack of financial support during droughts, and deficits during irrigation projects, and No specific budget for drought preparedness at the provincial level and below. Saline intrusion Lack of knowledge on drought preparedness, Lack of information on appropriate agricultural practices, Lack of technical capabilities and staff to advise farmers, Ill-informed communities and some organs of the government about the implications of climate change, droughts and the environment. Lack of community participation The large seasonal fluctuation in river flow results in changes in the hydraulic differential between river and oceanic water levels. During the dry season, low water levels in the river allow tides to drive salt water into approximately half of the CLD area (Fig 4). Salinity levels of 4ppt can penetrate 50km up the main channels and 100km up the tributaries such as the Vai Co River (Phuong, 2007). In Ben Tre province alone, saline intrusion was responsible for USD $37 million worth of damages and productivity losses during 2005 while almost 40% of the provinces population went without fresh water supply during the dry season (Oxfam, 2008). The management of saline intrusion is one of the key issues of WRM, because water salinity determines the type of activity that an area can support. There continues to be conflicts between rice and shrimp farmers, driven by the development objectives of the government, fluctuations in the domestic and international market price for rice/shrimp products and the desires and flexibility of local farmers. 13

Figure 5. CLD Water Resource Extremes: (left) Maximum salinity intrusion; (right) Maximum water level in flood season (T.V.Truong, 2008) Typhoons and storms Unlike the north and central coasts of Vietnam, the CLD has not been regularly hit by storms and typhoons. However, there have been some catastrophic typhoons in recent times, the most significant of which was Linda Storm (1997). Linda storm was travelling at 28m/sec when it hit Ca Mau Peninsula before crossing into the Gulf of Thailand, the typhoon destroyed more than 200,000 homes, ruined 500,000ha of farm and aquacultural land and killed 355 people (Table 4) (Dillion et al, 1997). The damage was amplified by the fact that the CLD was largely unprepared for such a disaster and therefore had minimal disaster response systems in place. Because storms originate in the Pacific Ocean, the impacts are concentrated around the coastal areas of the CLD. These areas also correspond to some of the highest levels of poverty and isolated communities. Table 4. Damage cause by Linda Storm in the CLD (SIWRP, 2008) Deleted: 4 DAMAGE UNIT CLD TOTAL IMPACT Dead no 355 Injured no 1,410 Missing no 1,437 Evacuated no 20,000 Boats (submerged/damaged/missing) no 3,196 Houses (submerged/damaged/collapsed) no 203,485 14

Rice Field (inundated/damaged) ha 285,895 Aquaculture (inundated) ha 230,200 Fruit trees & sugar cane ha 39,674 (inundated/damaged) Trees (uprooted) ha 40,614 Dikes (Destroyed) km 50 Dikes (breached) km 164 Culverts (collapsed) no 84 Estimated losses (billion VND) VND 5,237 Acid-sulphate soils Acid-sulphate soils remain a problem for 0.9 1.0 million ha of the CLD. The soil matrix is the result of fresh and marine water interactions, as sulphur from the oceans and nutrients from terrestrial flows formed a layer of sulphate and saline sulphate soils. Acidic waters are generated when exposure to oxygen initiates an oxidation process with acidic by-products contaminating the first flush of rain with detrimental effects on both the receiving environment and rice production. However, over time a complex layer of vegetation including floodplain wetlands, expansive grass plains and scattered Melaleuca formed a rich topsoil of decomposing organic matter which isolated the potentially acidic underlying layer from contact with oxygen, rendering them inert. Changes in land-use patterns most notably clearing for agricultural production and the control of wet season flooding has exacerbated the problem. Drainage works have had some success in flushing these acidic waters out to sea, limiting the problem to the months of May-August and November-January. The issue is compounded during dry years when there is a shortage of water. Table 5. CLD: General overview of the major risks CLD RISK FREQUENCY EFFECTS AREA EFFECTED Floods Annually (June Dec) sustains key ecosystem ~49% of CLD Water level ~4m (rising average ~5-7cm/d) Large Floods (>4.33m) have a 46% probability of occurrence functions provides water for agriculture destroys homes, infrastructure, farms can result in loss of life Saline Annually (dry season) Saline concentrations ~50km up the main Intrusion greater than 4ppt can change environments channel ~50% of CLD from fresh to saline Droughts last major drought peaked in 2004 small floods (<3.83m) have a 13% probability of occurrence loss of livelihood as agriculture was devastated water shortages for domestic use mainly effects coastal areas, the Plain of Reeds, and Long Xuyen Quadrangle, which can become hydrologically isolated from freshwater if the rivers do not breach Typhoons Last major storm 1997 (Linda storm), 2000 was also a significant event Destruction of homes and infrastructure (canals, roads dykes). their banks Coastal provinces (Ca Mau, Bac Lieu, Soc Trang, Ken Giang) 15

2. Climate Change Impacts for the CLD 2.1 Global perspective Although human-induced climate change has slowly been occurring over centuries, awareness of the phenomena is a comparatively recent development. Arguably it was not until the 1992 Rio Earth Summit that the issue began to receive international attention. Since then, progress on emissions controls has resulted in significant debate and few global measures. However, it should be remembered that there are two sides to the global climate change response; mitigation of emissions levels and adaptation to changes in the biosphere. CO 2 emissions have largely been the consequence of industrialization in the developed world and consequently their efforts have focused on emissions control. On the other hand, the developing world correlates to areas which are most vulnerable to the impacts of climate change and so adaptation has become an urgent necessity (World Bank, 2007; Oxfam, 2008). Scientific understanding There are two fundamental drivers of climate change, the natural or base fluctuations in global climatologic parameters, and the influence of anthropogenic activities. It is widely accepted that surface temperatures on earth have fluctuated dramatically throughout its history as part of ongoing long-term geo-physical processes, and these days there is also consensus amongst the scientific community that global temperatures are increasing. Furthermore, most research indicates that human activities have played a decisive role in accelerating this process during the last century, such that climate change is now happening faster than at any other stage in the earth s history. The Intergovernmental Panel on Climate Change (IPCC), one of the leading research bodies on the phenomena, have recently released their fourth Assessment Report (AR4). It concludes that the concentration of carbon dioxide in the earth s atmosphere has fluctuated around a natural range of values for the past 650,000 years, however, recent CO 2 levels have consistently exceeded this range (IPCC, 2007). Consequently, 11 of the warmest years, observed since instrumental records began in 1850, occurred during the last 12 years (IPCC, 2007). Furthermore, there has been an increase of 0.74 0 C in the average temperature during the 20 th century, with predictions of future global temperature rises in the order of 1.8 4.0 0 C (IPCC, 2007). These temperature changes will have effects across the biosphere, but especially to the hydrological cycle, including changes to sea levels, precipitation and monsoon patterns and glacial melt. Globally, climate change is expected (with a high degree of confidence) to have an overall negative impact on freshwater systems (IPCC, 2007). Sea levels have already risen by 17 cm during the past 100 years and are predicted to continue rising. Predictions of the magnitude of sea level rise vary greatly. 16

2.2 Regional perspective Viet Nam is located in the tropical region of Asia and is potentially one of the countries where a rise in sea level could have the most dramatic impact with nearly a quarter of its population directly affected (World Bank, 2007). The IPCC suggests that Vietnam is also likely to face both drought and changes to the prevailing precipitation and flooding regimes (IPCC, 2007). Viet Nam has a population of 84 million, the majority of whom live along its 3,200 kilometres of coastline. It suffered 10 typhoons and severe storms in 2007, and concentrates much of its food production in the low-lying Mekong and Red River deltas. If sea levels rise by one metre, Vietnam would lose more than 12 percent of its land, home to 23 percent of its people. Climate change could also increase the frequency and severity of typhoons, and rising temperatures and changing rainfall patterns would also affect Vietnam's agriculture and water resources. Vietnam s economy grew by over eight percent last year, and is one of the fastest growing economies in Asia. At the same time, it is also emitting more pollutants, with the amount of greenhouse gases (GHGs) released projected to increase by a factor of 2.3 during 1994-2020. The IPCC Technical Paper on Climate Change and Water (Bates et al, 2008) outlines the effects that Climate Change is having on the hydrological cycle. By the middle of the 21 st century water availability is expected to shift away from arid, semi-arid and dry tropical areas towards wet tropical and higher altitude areas. Therefore, river run-off is expected to increase in parts of the LMRB, and there is a likely increase in the risk of flooding and drought, with an increase in the frequency of heavy rainfall and extreme events (typhoons, hurricanes), simultaneously, drought frequency is increasing and lasting longer. Natural disasters in China will challenge the integrity of large hydropower projects, both of which could have disastrous effects on the downstream communities and ecosystems of the LMRB. Traditionally, typhoons have been a problem for central and northern Viet Nam, however global warming is likely to see typhoons tracking further south as well as becoming less frequent but more catastrophic. Increasing water temperatures and changes to flooding/drought regimes are expected to affect water quality, exacerbating effects from pollution such as sediments, nutrients, pathogens, pesticides, dissolved organic carbon, and salt. There will be significant economic, environmental and health-related ramifications for human communities. These changes to the hydrological cycle are expected to reduce food security and increase vulnerability of rural farmers, especially in the Asian megadeltas. Additionally, climate change is compounded by other global development problems of rapid population growth. The UN predicts that for the first time in the world s history 2009 will see one billion people suffering from hunger. 17

2.3 Local perspective Climate change is altering the flood regime in the Mekong Delta. The following are some key problems associated with these changes: Table 6. CLD Summary of the Impacts of Climate Change Environmental Impacts Of Climate Change Characteristic Temperature Temperature increase by 0.1Deg C every decade 1931-2000 Rainfall Annual rainfall average is constant but greater polarization of wet and dry seasons Higher frequency and longer duration of drought in southern areas of Vietnam, Storms Fewer typhoons, but greater intensity/severity and they are tracking further south Sea Levels Sea level rose 2.5 5.0cm each decade for the last 50years SLR 30-35cm (2050), 40-50cm (2070), 60-70cm (2100) River flow Mirrors increased polarization of rainfall Flows in the Mekong to increase 7-15% in the wet season, decrease 2-15% in the dry season Increased erosion Decreasing water and soil quality, and poorer plant health Floods Floods last longer and arrive earlier (especially in Long An province), with higher levels of inundation in and along the Cambodian border. Increased areas with flood control (i.e. three crops and inundated all year) which results in a reduced buffer capacity for flood regulation, limiting of sediment deposition, declining yields of natural fish stocks, increased risk of diseases, limiting of river traffic and increased pollution. Biodiversity Severe reduction in natural fish stocks Sea Level Rise (SLR) The quantification of SLR is difficult, because it incorporates several biophysical processes, such as glacier and terrestrial ice sheet melt, thermal expansion of the ocean column, snowmelt, and changes to the water content in terrestrial and atmospheric regions (figure 6). These factors need to be modeled separately and then combined to give an overall indication of SLR. Therefore, estimates of SLR by 2100 range from 0.5m to 70m (BBC, 2008). The process which is least understood is the melting of glaciers and terrestrial ice sheets, consequently the IPCC omitted these factors in their estimates of SLR, predicting that SLR would likely be less than 2.0m by the end of this century (IPCC, 2007; BBC, 2008). A study by the World Bank (2007) on the impacts of SLR on developing nations modeled SLRs of 1.0, 3.0 and 5.0 m, with 1-3 m being considered realistic. The results of the World Bank study are sobering for Viet Nam. Of the six critical elements under study, Viet Nam was the most effected nation in the world for four of these categories (Wetlands, Urban extent, GDP, population) and the second most affected for the 18

remaining two categories (Land area, agricultural extent) (World Bank, 2007). Furthermore, most of these effects will be concentrated on the mega-deltas of the Mekong and Red rivers. There are three measures to cope with sea-level rise: protection, adaption and withdrawal. The first step towards effectively coping with SLR is a thorough study to quantify and determine specific regional areas that will be affected by SLR in accordance with development scenarios. The simulations of impacts of the nature and the socio-economy under different sea-level-rise and upstream development scenarios need to be implemented in order to find out reasonable measures/solutions. For water resources development, the ready-made plan needs to be re-planned, calculated, supplemented, adjusted in accordance with new parameters/values of hydrological and hydraulic division, and initiate the short-term and the long-term structure and non-structure measures/solutions. The above assessments are based only on the forecast of IPPC and WB, as well as preliminary estimation of SIWRP. However, newest information on climate change and sea level rise on the world recently shows that the trend of sea level rise progress will happen faster than previously forecasted. The phenomena of sea level rise exist and cannot be avoided. Therefore, considerations to cope with effects of the sea level rise at this time are really urgent and essential. Figure 6. Magnitude of response of various biophysical components of Sea Level Rise (DWR, 2008) Deleted: 5 Deleted: 19

Figure 7. Proportion of critical impact elements affected by 1mSLR in Viet Nam (adapted from: World Bank, 2007) Deleted: 6 Rainfall regime There will be increased inter-seasonal variability between the wet and dry seasons affecting precipitation regimes. One study suggests that rainfall will increase by more than 17% in the wet season and reduce by more than 27% during the dry season (see Figure 7). This is likely to increase the frequency and severity of droughts as well as of floods. Figure 8. Predicted Max/Min % changes in flow averages (adapted from: Hoang et al, 2004) Table 7. General Summary of Climate Change impacts on the CLD SECTOR IMPACTS OF CLIMATE CHANGE Water Increased variability between wet and dry season rainfall Resources Increased frequency and severity of droughts and climate extremes Growing disparity between water supply and demand signatures Increased vulnerability to changes in the flow regime and river regulation (e.g. from hydropower) Agriculture, Changes to plant growth, yields, disease risk & crop failure Forestry & Altered timing and number of annual crop cultivation cycles National food Increased risk of plant disease security Reduced available arable farm land Increased fire risk and anthropogenic deforestation/forest degradation Increased vulnerability to continuing deforestation which will alter runoff regime in the upstream catchments of Laos (where 30% of flow originates). This could increase sediment loads and exacerbate worsening flooding problems & infrastructure inefficiencies in a warming climate Fisheries Reduced habitats for freshwater species Increased aquaculture potential Transportation, construction and industry Increased flood risk for roads Increased erosion of road surfaces Increased risk of low flow conditions inhibiting navigation Increased erosion in wet season (already 70 identified sites of Deleted: 7 20

erosion) Disasters General increase in the frequency of natural disasters Typhoons tracking further south and hitting with increasing severity Population Increase in environmental refugees and migration pathways Increased urbanization will place greater strain on water shortages which are likely to last longer and become more pronounced with climate change 2.4 Qualitative Assessment of Climate Change Risk The field of ecology owes its development and success to a recognition that the scale of inquiry is fundamental for a more accurate understanding of the biophysical processes, and climate change itself, is perhaps the highest profile example of the importance of scale. In the past CO 2 emissions were seen as inconsequential, because they seemed small in comparison to the size of the atmosphere, but at the global scale and over a hundred year time frame they managed to induce an incremental change in the atmospheric temperature which has produced much more influential subsidiary effects that now threaten many human communities. The risk facing the CLD is occurring over two temporal scales. On the one hand, WRM must plan for the day-to-day realities of communities, matching water distribution, quality and development to long-term socio-economic and ecological needs of the community and their living environment. On the other hand, WRM must also accommodate for disaster management, mitigating the impact of disaster events on the local community as well as providing for emergency response measures in service and rehabilitation. While the management initiatives for many of these issues may overlap, and others may already exist, climate change will force better coordination of efforts at all spatial and temporal scales. Lastly, Viet Nam and the CLD in particular, must acknowledge that while they played only a minor role in the escalation of human-induced climate change, they must take control of adaptation responses to the subsequent impacts, and look to encourage large emitters to do the same. 3. Water Resource Management - mitigation and adaptation initiatives for Climate Change 3.1 Integrated Water Resource Management (IWRM) Role for climate change mitigation and adaptation Water resources in the Mekong River, are defined by the Mekong River Basin, which extends over 6 countries, 60 million people and many different ethnic groups and climatic regimes. The Mekong River, therefore, is a prime candidate for Integrated Water Resource Management (IWRM). IWRM concept and history 21

IWRM is defined as a multi-resource management planning process, involving all stakeholders within the watershed, who together as a group, cooperatively work toward identifying the watershed s resource issues and concerns as well as develop and implement a watershed plan with solutions that are environmentally, socially and economically sustainable (ADPC, 2006). Additionally, IWRM acknowledges that the scale of inquiry, when addressing issues, is fundamental to the type of solution that will be generated. This approach constructs local issues as nested within the broader context of basin decision-making (Miller, 2003). It recommends that issues be seen in the context of the whole river basin, so that all stakeholders can have their concerns and interests addressed and negotiated resolutions to problems can be generated in the most equitable manner. Additionally, water resources, while being a sector onto itself, is also an important component of many other sectors of riparian communities consequently IWRM planners need to be conscious of the externalities that drive water resource exploitation. The introduction of IWRM is closely tied with the emergence of the Mekong River Commission (MRC), which first manifested as the Mekong Committee, a UN-led initiative in 1957 (MRC, 2008). At that time the LMRB was seen as one of the world s great untamed rivers and its vast reserves of freshwater could form the backbone of economic development in the newly emerging independent nations of the basin. Earlier efforts were inspired by the example of the Tennessee Valley Authority (TVA) which in its prime was considered one of the basin-wide management success stories (Miller, 2003). During the 1960s US engineering skills were transported to the Mekong in line with the TVA model to develop its hydro-electric potential. This can be seen as the precursor to IWRM in the LMRB, when engineering-based intervention with a strong sectoral focus looked to kick-start economic development (Miller, 2003). Then political instability led to the collapse of the Mekong Committee in the late 1970s, to be reborn in 1995 as the MRC with a new mission of sustainable development for the Mekong River Basin. At this time one of the leading examples of best practice was the Murray- Darling Basin in Australia, however, both this and the previous TVA model were developed in post-industrial societies and their transference to the LMRB was based on some assumptions which have suffered some criticism (Miller, 2003). According to Miller (2003) the issue is not so much one of whether or not international experience is relevant, but rather of what is relevant packages and models, or processes and principles? and if it s the latter, then how can development initiatives improve on their ability to pass on processes and principles in vastly different socio-economic environments and in the midst of political and cultural institutions that bear little in common with those where the IWRM models were first proposed and developed. As will be shown, these concerns remain relevant to the CLD today. In 1995 the Mekong River Agreement (MRA) was signed with the main purposed of regulating the construction of hydro-dams on the Mekong mainstream. Then, IWRM was formally coupled to the Vietnamese political will in the government s 1999 Law on Water 22

Resources. This law was the first of its kind in Vietnam and a major step forward for IWRM. Specifically, the Law addressed (Biltonen, 2008): Water rights and the right to benefit from the use of water resources; Responsibilities of users to protect the water resource and to prevent and overcome any harmful effects of water; The development of water resources in areas with difficult socio-economic conditions; The development of fee-based permit systems for wastewater discharge The combination of national and regional efforts then led to the formation of River Basin Organizations (RBOs) for the Red River, CLD and Dong Nai basins in 2001. However, since the Government of Vietnam believes that the current political institution adequately addresses the needs and interests of the people, the RBOs are seen more as a coordinating body between institutions at different administrative scales (Molle, 2005). Consequently, RBOs have been given the weakened mandate to: advise the Minister of MARD on planning and development projects, management mechanism, policies on other issues relating to management, exploitation, utilization and protection of water courses in the river basin (Su et al., 2004). One of the main problems with the RBO is that it was translated across sociopolitical contexts. There is an urgent need for a recontextualization of RBOs to suit the LMRB, where economic growth and development is varied between member countries IWRM application in the CLD The main goals of the water resource management program in the CLD is to; protect people s lives, minimize property damage, promote sustainable socio-economic development; develop storm and flood control and rescue/relief organizational apparatus from province to district and commune; improve staff capacity and provide more equipment. These key concerns inform detailed plans and benchmarks set up to track the success of development in the CLD up to 2020.The past two decades has seen good progress towards developing reasonable policies and mechanisms for flood-prone areas of the CLD. However, there are still some shortcomings that will require extra work. Many regional and national actors in the Mekong Basin have identified the incredible and largely untapped agricultural potential of the catchment, often denoting the Mekong Basin as South East Asia s rice bowl, with the economic capacity to lift the region out of poverty (Cornford et al, 2001). Indeed, the Mekong Delta is instrumental in reducing poverty, stimulating the national economy and developing Viet Nam. Today, Viet Nam is seen as one of the Asian development success stories and one of the few countries on track to meet its Millennium Development Goals (MDGs) (Oxfam, 2008). At a national level, it was able to reduce poverty from 58% in 1993 to just 18% in 2006, a remarkable achievement driven largely by strong economic growth, pro-poor development policies and strong governmental commitment (Oxfam, 2008). The most significant economic growth was in the Mekong and Red River deltas, where water resource planning was able to increase yields as well as facilitate up Deleted: 23

to three crops each year. The Vietnamese government generated a lot of reform from within its institutional structure, cooperating with international efforts, restructuring its economy and quickly expanding the nation s technical/knowledge capacity, as well as becoming a key stakeholder in multi-lateral groups such as the Mekong River Commission (MRC). Furthermore, water resource management in the Mekong River Basin is at different stages of progress. Vietnam, along with Thailand and China, have widespread irrigation development and infrastructure investment, while development in the other MRC countries and Myanmar have been hindered by war, political conflict or small isolated populations (as is the case for Laos) (Molle, 2005). For example, Thailand is the regional leader in river bank protection, while on the opposite bank of the river, Laos is unable to provide the same service and in some places between 9 30m of river bank erodes annually (Kummu et al (eds), 2008). Table 8. Shortcomings in the existing flood management system, by sector (adapted from: Phuong, 2007; White, 2002; KOICA, 2000) SECTOR SHORTCOMINGS Economic Insufficient economic incentives for farmers to adopt mitigation measures, and poor rural credit for financing flood control measures Insufficient funds to increase the frequency of maintenance works on drainage/irrigation infrastructure, which are underperforming due to inefficiencies and sediment build up. Environmental Absence of environmental management plans (EMPs), pollution control measures & flood risk insurances Institutional prioritization of hard engineering flood control works, to the detriment of wetland, mangrove and forest ecosystems Social Insufficient number of full-time staff working in the Storm and Flood Prevention Committees Organizational, operational and technical capacity problems with the Storm and Flood Control Search and Rescue Steering Committee High levels of poverty in some areas Organizational Overlap of duties and responsibilities in some organizations, Some incoherency in legal/policy frameworks, and administrative boundaries and responsibilities at the provincial and local levels Lack of integration between policies at the central (national) and local levels Analysis of the effectiveness of institutions, mechanisms and policy has not been integrated with projects Low level of national investment in agricultural and flood management/mitigation works. This means that the 5,000billion committed for water resource works up to 2020 amounts to only one quarter of the amount likely to be needed Future directions In recent years developed countries, with low population growth rates, have seen a shift in Water Resource Management priorities. In the past improving supply and harvesting techniques was the key priority, so that supply could keep up with demand (Ghassemi et al, 2007; Miller, K., 2005). Now priority is given to water conservation, reuse and improving system efficiencies, which has seen the emergence of more sophisticated and well researched water 24

pricing, trading and reuse options (Ghassemi et al, 2007). However, in developing countries characterized by rapidly increasing populations, economies and water needs, the main concern is to satisfy regional water and energy needs (Ghassemi et al, 2007). The problem facing the developing world remains how to translate the lessons and successes of the developed world to the developing context. This is reflective of the types of problems and issues facing all riparian countries in the Mekong River Basin, but it is especially the case for Viet Nam, because of the high population density in the Mekong Delta (~423pp/km² compared to ~183pp/km² in the Cambodian delta) and an average regional growth rate of 8.6% (VCCI, 2008; KOICA, 2000). Exactly when demand management of water resources is introduced in the LMRB and CLD, largely depends on the willingness of the international community to cooperate with riparian countries. Financial and technical support from countries with experience in demand management would allow the CLD to prepare for the issues and environmental consequences of a demand-supply imbalance before the impacts reach dangerous levels. IWRM in the CLD In the CLD improvements in food production, meant that the national priority of production to feed the country s population could be diversified to include other agricultural/aquacultural products. However, the increasing complexity of agricultural production, water management and environmental issues meant that an integrated approach was required. To this end, a Dutch consultancy (NEDECO) helped draft and implement the first Master Plan for the CLD in the early 1990s. The Master Plan was based on an Agriculture- Fisheries-Forestry Development Model, the primary aims of which, were (Truong et al, 2001): limit saline intrusion to 5-10km into terrestrial environments; control early flooding and dissuade triple cropping in protected areas; extend canal network down to the tertiary network; continue diversification of agricultural production, as well as reduce its impacts on fisheries and wetland ecosystems, and; research into potential agriculture-forestry-fisheries production models that are both sustainable and viable Initially, this accelerated the implementation of hard engineering solutions, including the construction of wide spread flood control structures in the 1990s. By 2001 there was 2-5m of canal/ha in single-crop areas and up to 10m/ha in triple-crop areas (Truong et al, 2001). Also an extensive system of sea dykes began to be built reducing the area affected by salinity intrusion to 1.1-1.2million ha (~30% of CLD) (Truong et al, 2001). The Vietnamese government, under the impetus of climate change, is now making a concerted effort to explore soft engineering solutions such as vulnerability reduction and the use of mangrove buffers, which are considered an area of research in the National Target Plan (NTP) (see below). 25

Figure 9. Agriculture-Fisheries-Forestry Integrated Development model for the CLD (T.V Truong et al, 2001) By 2005, 7.4million hectares of the total Mekong Delta were under irrigation either by natural rivers or man-made canals, with approximately 750 large or medium sized reservoirs. The extent of the irrigation network reflects the speed at which water demand is growing in the delta, driven primarily by the intensification of agricultural activity. Water demand increased by 30% between 1990 and 2000, averaging a 3% increase per year (Molle, 2005). Therefore, in 2010 the water demand is estimated to reach 74billion cubic meters. The government, supportive of the rapid rate of economic growth and the subsequent benefits to the national economy, has made serious financial and policy commitments to supporting the CLD agricultural sector. Primarily this support is conceived of as hard engineering solutions such as the building of dykes, sluices, embankments as well as crop diversification and encouraging the use of pesticides. The Ministry of Agriculture and Rural Development (MARD) has estimated that, independent of climate change, a budget of $750million USD is required for building and repairing the CLD dyke system between 2010 and 2020, (Oxfam, 2008). These are prioritized by MARD because modern hydraulic infrastructure has been essential in developing the agricultural sector, and since this sector now accounts for approximately one quarter of the national GDP and exports and accounts for two thirds of national employment, infrastructure investments into the agricultural sector will bolster economic development (Molle, 2005). An alternative to building infrastructure is to use soft engineering approaches. For example, the Vietnamese Red Cross (VNRC) have been studying the use of mangroves to protect coastlines in some of the northern provinces of Viet Nam since 1994. So far, the project has grown almost 22,500ha of mangroves, involving the efforts of some 265,000 community members, students, teachers and VNRC staff, and resulting in the protection of approximately 100km of coastline (CARE, 2007). Mangrove areas can protect communities and existing sea dykes from storm damage. Research has shown that 100m of mangrove forest was sufficient to reduce the amplitude of tidal waves by 50%, and the energy by up to 90% (CARE, 2007). In fact a comparison of a 1996 and 2005 typhoon found that there were significant improvements, no loss of human life, and a significant drop in property damage after the mangrove program was established, while the mangrove survival rate was ~62.5% (CARE, 2007). A secondary benefit is that the people living in coastal areas are typically poor and often marginalized from the benefits of most economic growth. Re-establishing the mangroves offers them the ability to supplement their income with forestry products, such as seafood, bee-keeping, Deleted: 8 26