The Mekong River Basin Development Plan (BDP): Perspectives
of the Mekong Delta in the Basin-Wide Context.
by Ho Van Cao,
Ph.D. 4/1998
I. EXECUTIVE SUMMARY
II. KEY ISSUES FOR MEKONG BASIN DEVELOPMENT PLAN
(BDP)
1.Approach
to Mekong Resource Development Within Vietnam Economic Framework.
1.1. The Mekong Basin in Vietnam
1.2. Key Concerns: Salinity and
Acidity Management
1.3. Basin Development Plan
(BDP) Must Embrace Programs to Support Salinity and Acidity Management in the Delta
2.Upstream-Downstream
Issues of Water Sharing
2.1. Negative Factors: Interbasin and Intrabasin Water
Diversion in Thailand
2.2. Negative Factors: Deforestation’s
Adverse Effect on Watershed for Dry Season
2.3. Looking for Alternatives: Intra
/ Interbasin Water Diversion Vam
Co/Mekong in Vietnam
2.4. Looking for Alternatives:
Revisited Tonle Sap Great Lake Option for Downstream Delta' Benefits
2.5. Looking for Alternatives: Intra
or Inter basin Water Diversion in China for Downstream
Nations'
Benefits
3.BDP Focus:
Restructuring the Delta’s Economic Base to Improve Living Standards and
Reduce
Poverty in the Delta
3.1. Poverty Reduction as an
Integrated Element of Delta BDP
3.2. Restructuring the Delta's
Economic Base
3.3Major References
Bio
Sketch of the Author:
Ho Van Cao obtained his doctoral degree in Economics from
Georgetown University, U.S.A (1973). He was a former Assistant Minister of
Finance and Government Commissioner of Industrial Development Bank of Vietnam. He was a member of the National Petroleum Board and Presidential
Cultural and Social Commission. Notably, he was an Administrative Chief of a
district peripheral to Dong Thap Muoi
(Plain of Reeds), worked and lived with Delta people whose heels tarred with “phen” (sulphate soils). One of
his pen names is NGUON PHIEN (Pure Sulphate Nodule).
In spite of his pen name, he is an advocate for any solution to eradicate ASS
(Acid Sulphate Soils) including the Anaerobic
Treatment Process if it becomes a proven method.
I. EXECUTIVE SUMMARY
The 1995 Agreement on
the Cooperation for the Sustainable Development of the Mekong River Basin
requires all 4 riparian Governments to come up with a BDP serving as a blue
print for sustained development of the Mekong basin. Phase
One covers the Terms of references (TOR) for the BDP. Phase Two focuses on the
formulation of the BDP. This paper identifies major elements should be
addressed in the Mekong BDP with reference to the Mekong Delta Perspective.
The Mekong BDP must take into account unique
characteristics of the Delta in its grand scheme for development. There exist
three sets of unique problems facing the Delta, on an unequal scale, not found
in other places basin-wide:
·
The salinity intrusion during the
dry season
·
The acid sulfate soils in large
areas of Dong Thap and Long Xuyen
Quadrangle
·
The low level of the inner Delta
area comparative to the sea-level estuaries, a prime factor aggravating many of
the Delta's environmental issues.
Mekong Delta's hard realities and vivid
experiences necessitate a sensitive stakeholder approach to BDP formulation and
design.
Mekong Delta residents
have learned to live with the seasonal annual floods calmly faced devastating
great floods in the past, which caused losses to harvest, crops, human lives,
properties, and livestock. However, they
cannot bear the misery of deeper and
deeper penetration of saline water into the inner Delta areas during the dry
season.
They have high hope to
see the Dong Thap and Long Xuyen
Quadrangle cease to exist as uncultivable acid sulfate soils. New canals were
built, drainage and sulfate washing have been applied but they obtained no
success in large scale. Effective ways to deal with acid sulfate soils become
more pressing under the pressure of rapid growth of the Delta population which
surpasses 15 million, more than the size of the combined population of the two
neighboring riparian countries--Cambodia (8.9 million) and Laos (4.6 million)
--.
They continue to
suffer inadequate drinkable fresh water supply, which is, in many areas,
contaminated by waste and toxic/mineral elements dissolute in the river flow, a
chronic problem aggravated by the low-level of the Delta inner are comparative
to the sea-level river estuaries. The semi-diurnal tides of the South China Sea affect the way of
life of Delta residents for better or for worse. In addition, the reduced
spread of the fertile silt to the Delta has forced Delta farmers to rely more
on inorganic fertilizers to maintain the crop production. The intensive use of
fertilizers has dumped more chemicals into the river; notably the nitrate
penetration into groundwater has produced harmful effects to human beings, and
children's growth.
All in all, the Mekong Basin Development Plan,
stipulated by the 1995 Agreement on the Cooperation for the Sustainable
Development of the Mekong River Basin, serves as a framework for development and cooperation acceptable to
four riparian countries. The BDP provides a blueprint for water resource
development fostering the economic and social well being of all people living
in the basin. The wide range of needs and environmental factors Basin-wide and
Delta-wide necessitates a sensitive stakeholder approach to BDP formulation and
design. The Mekong BDP will not encourage any development that puts economic growth before
equity and sustainability, at the obvious expense of other regions in the basin
including the Delta.
II. Mekong Basin Development Plan
(BDP): Delta-wide Context
Recognizing that the Mekong BDP is not the only initiative
exists in the basin, the BDP must be drawn in
coordination with the ADB-sponsored Greater Mekong Subregion
(GMS) initiative, initiated in 1992. However,as a whole, the GMS initiative does not exhaust the
water resources development/management of the Mekong basin including the Delta. Riparian
countries cannot be content solely with these feasible projects as they are
sponsored by ADB or potentially financed by ADB. On Delta perspectives and
context, the strategic focuses and development roadmap can be structured within
the BDP framework and suggested on several prongs to embark effective salinity
and acidity management in the Mekong Delta. As the availability of freshwater is central to salinity and
acidity management, watershed management is an issue at basin-wide level,
therefore BDP should address all factors and options related to upstream/
downstream water sharing. Last but not least, poverty reduction and
restructuring the Delta's economic base must be treated as integrated elements
of the BDP.
Controlling deeper salinity penetration. This implies to maintain a
normal/minimum river flow during dry season. The status quo option is the
equitable water diversion of upper riparian countries during dry season. In
spite of geopolitic hurdles and technical challenges
posed by topology of the upstream hinterlands, feasibility studies of intra or
inter basin water diversion upstream to be explored: some sort of Lake Victoria
and Lake Albert-type which are the feeding sources for Nile river during the
dry season.
Technical assistance
on a global scale for feasibility study focuses on identifying tributaries of Mekong or Salween Rivers, which can be converted into huge lakes serving that purpose. With such
lakes, normal flows of the Mekong during dry season will become more stable and the salinity penetration
become less severe. Benefit-cost analysis must be performed. But the benefits
will outweigh the costs to implement such reservoirs, compared to dam building
for hydropower. Controversial intra or inter basin water diversion in Thailand need to be reexamined. Deforestation's disastrous effect on watershed
in the dry season must be stopped by
effective forest protection measures and reforestation. The Mekong’s natural regulator --Tonle Sap-- must be revisited with its great role as regulating water body for the
benefit of the whole
Delta under some sort of international supervision. Intra-basin water diversion
from Vam Co River into Mekong and inter-basin water diversion
into multipurpose reservoirs to store floodwater in the Delta must be explored
as alternative options. We should not leave any stone unturned. As such MRC lives up to the fullest meaning of its new role
empowered in 1995.
Finding ways to effectively deal
with acid sulfate soils with cursory research on alternative interdisciplinary
approaches including the anaerobic treatment process and sulfate burying such
as creating multi-purpose large-scale water reservoirs in the Delta's Dong Thap and Long Xuyen Quadrangle to
entrap silt buildup and provide source of freshwater in the dry season.
Alleviating ecological degradation in the
Delta on many fronts: Reducing the intensive use of fertilizers in Delta
farming. This implies to maintain the rich silt content of the river flow and
the larger spread of silt in the Delta during the wet season. Maintaining quality of ground water supply for human habitation and
other domestic uses.
Reducing water use for Delta's
agricultural farming by 10 - 15 percent by promoting agricultural
diversification and industrialization in the Delta by 2010 resulting
a shift in Delta's total target output in agriculture and industries:
By the year 2010, Mekong Delta will still be an important
agricultural sector of Vietnam, but its economic base shifts to a lower share of agriculture in the
GDP (50%), manufacturing (26%) and service (24.0%).
The projected shift in Mekong economic base will produce a net
gain of 5 percent in GDP, bringing Mekong Delta regional share in GDP from 22.8 % in 1995 to 27.8 % by 2010.
KEY ISSUES FOR MEKONG BASIN DEVELOPMENT PLAN
(BDP)
Let start with some thoughts of good will and positive thinking. In lieu of MRC has been perceived as an agency set up to promote the
construction of controversial dams and water diversion of the Mekong and its tributaries.
MRC has expressed
support for a run-of-river plan for large-scale hydropower developments.
Positive thinking: MRC serves as a channel
for regional action in the Mekong basin to foster more integrative and sensitive approaches to Mekong resource management and
development.
China and Burma’s non-membership
hampers the role of the MRC. China in particular is a
significant player as the country that contains half the length of the river
and 16 per cent of its flow. China has unilaterally
built the first mainstream dam and others are under construction or being
planned. China has least to gain from Mekong Basin cooperation, both as the
upstream country and as the dominant power in the region.
Positive thinking: A truly Basin-wide
program needs to take account particularly of China’s key role in Basin
resource management. Significant flow alteration by upstream diversion and
large hydropower dams would affect the Delta. The new MRC Agreement with the
other Lower Basin countries has
removed veto rights for intra basin
projects during the wet season. . A significant change from the Committee rules
is that downstream countries no longer have an effective veto on upstream
developments. Rules are structured around notification and consultation on
projects that affect dry season and wet season water flows. This was a point,
which contributed to Vietnam’s reluctance to sign the agreement when it was first proposed in 1992.
Only 36 per cent of Thailand’s territory are in the Basin, but Thailand is nevertheless a significant player. In part this is due to potential
use of Mekong water on its own territory, with two major diversion schemes planned
that could affect downstream flows
Positive thinking:
Thailand will refrain from carrying out the inter-basin diversion scheme from
the Thai Kok and Ing
tributaries to the Chaophraya basin The planning tool
to be used by the MRC is the Basin Development Plan (BDP) which is defined in
Chapter II of the Agreement as the "general planning tool and process that
the Joint Committee would use as a blueprint to identify, categorize and
prioritize the projects and programs to
seek assistance for and to implement the plan at the basin level".
Positive thinking: The
goals of the BDP include bringing environmental and social issues into the assessment of MRC
actions. Recognizing that the Mekong BDP is not the only initiative exists in the basin, the BDP must be
drawn in coordination with the ADB-sponsored Greater Mekong Subregion (GMS) initiative, initiated in 1992.
There are approximately 100 competing projects identified under the GMS program
for infrastructure development --transport, energy, and telecommunication-- and
environment and human resources related projects, but, as a whole, they do not
exhaust the water resources development/management of the Mekong basin including the Delta. Riparian
countries cannot be content solely with these feasible projects as they are
sponsored by ADB or potentially financed by ADB. The Mekong BDP centers on seven water-related
activities:
- Agriculture
- Fisheries
- Forestry/Watershed management
- Hydropower (Energy)
- Navigation and Transport
- Tourism and Recreation,
- Urbanization and Industrialization
These water-related
activity programs are to be developed under two cross-sectional themes of
environmental/ecological balance and human resource development. On Delta
perspectives and context, the strategic focuses and development roadmap can be
structured within the BDP framework and suggested on several prongs as detailed
in this paper:
Salinity and acidity
management in the Mekong Delta The availability of freshwater which is
central to salinity and acidity management Watershed management is an issue at
basin-wide level, therefore BDP should address all factors and options related
to upstream/downstream water sharing
Last but not least,
poverty reduction and restructuring the Delta's economic base must be treated
as integrated elements of the BDP.
1.Approach to Mekong Resource Development Within Vietnam’s Economic Framework.
1.1. The Mekong Basin in Vietnam
Vietnam is the last downstream nation of the Mekong Basin. Within Vietnam, the
Basin covers 29% or approximately 96,000 square kilometers of the nation’s
total area and is represented by two disparate regions, the Mekong Delta and
the Central Highlands, excluding a relatively small area in Dien
Bien (1,392 km2), upstream of Nam Ou,
part of Nam Rom sub-basin.
The Mekong Delta spans 39,500 square
kilometers (12% of country total). Its vast deltaic plains is
formed by sedimentation and erosion. The Delta has been constructed over time
by overbank flooding and sediment drifting southwest
along the coast from the Tien and Bassac
nine-channel mouths. Monsoonrains from late May and
peak in September and October, in combination with floodwaters from the Mekong,
cause annual flood and inundation in about 1.2 to 1.4 million ha from two to
six months.
Discharge of the lower
Mekong during the wet season averages of 39,000 m3/sec.
In contrast, in the dry season, low water discharge is 1,700
m3/sec. In the ebb season during February-May period, salinity is most
severe, as river flow is inadequate to prevent seawater intrusion.
The Mekong Delta is crucial to Vietnam as its "rice bowl", the richest agricultural area in the
country. It accounts for half the rice production, 40% of total agricultural
output, and 27 percent of Gross Domestic Product. Increased agricultural
production has fuelled the economic liberalization or "doi
moi" since the mid 1980s and the Mekong Delta has been instrumental in this
continuing process. The Mekong Delta provides a home for slightly over 15 million people (22% of
country total), making it the second most densely populated region in Vietnam.
The Central Highlands cover the upstream
areas of two Mekong tributaries, Se San and Sre Pok rivers.
The Se San river originates from the Ngo Clinh Mountains and is the largest eastern tributary of the Mekong. This part of the Basin is typified by steep topography, has large
hydropower potential and forestry resources. The monsoon rains in the area last
from June to October and the run-off in the wet
season accounts for approximately 80
percent of the yearly volume. The Central Highlands are relatively
underdeveloped, has the lowest population density in the country with about 3
million people (4% of country total) living in an area of 56,000 square
kilometers (17% of country total). It is the home of many ethnic minorities. In
recent years, this region has experienced high levels of in-migration with the
highest population growth rate in the country of 5.8%. The central Highlands are important for upland
agriculture especially for cash crops such as coffee and tea, and hydropower
potential. The second largest dam in Vietnam, the 700 MW Yali
Falls Dam is under construction since 1994 and will be completed before the end
of the century There are many on-going projects supported by MRC for this part
of the basin: the 66 MW Vinh Son dam, the 120 MW Pleikrong dam, the Ea Soup multipurpose project and the
Upper Sre Pok basin
development plan.
In a capsule, the two regions comprising
the Mekong Basin in Vietnam are characterized distinctly by its unique population composition,
ethnicity, income levels and other socio-economic factors, topology, and
ecosystems. They underscore approaches to natural resources development in Vietnam, a sustainable development with broader concerns for environment. Rapid
and sustainable development of the Mekong Delta is central to Vietnam’s sustained growth.
1.2. Key
Concerns: Salinity and Acidity Management
For Vietnam, key concerns are reduced flows of water from the Mekong River during the dry season
and increased flooding during the wet season. Recent increased flooding has
been attributed to upstream deforestation. Nevertheless, the yearly overbank flooding is a disguised blessing to the Delta
because flooding is helpful to flush the acid soils, to deposit fertile
sediment into the floodplains, and to bring nutrients to inland fisheries. As
far as hydrological constraints to agricultural possibilities in the Delta, a
depth of prolong flooding of 60 cm is the threshold for rice cultivation-- too
deep for any varieties of rice, or any upland crops such as pineapples or
sugarcane—impractical to construct too high raised beds.
Above all, reduced
flows of water during the dry season are the biggest concern. Salinity
intrusions are closely linked to flow rates through the river system and any
decrease in flow will cause extensive problems for agriculture and human
habitations. The problems posed by acid sulphate
soils, which are common in the Delta, are also exacerbated by reduced flows. In
other words, the Delta is facing reduced source of water availability to
alleviate two major soil constraints, namely soil salinity and soil acidity.
Salinity Intrusion
Salinity problems arise
in the Delta, as the tidal effects throughout large areas of the Delta.
Salinity intrusion occurs during the dry season from February to May as
freshwater flows are reduced (Figure 2). This problem appears to be worsening,
and upstream developments within Vietnam and in other riparian countries could exacerbate the situation.
Salinity penetration extends into branches of the Mekong ten to forty miles. About 1.6
million hectares of the Mekong Delta are affected by saline intrusions during the dry season. Saline penetration
is more extensive in the smaller tributaries and canals compared to the Tien and Bassac Rivers.
The maximum salinity
reaches 4.0 p.p.t around April.
Even worse, salinity intrusion makes the irrigation water in the canals become
saline, i.e.; fertile soils cannot be used for agriculture due to lack of
freshwater.
Along the South China Sea, there are coastal
areas of Long An, Ben Tre, Hau Giang and Minh
Hai provinces, which are permanently saline because
they are inundated by seawater more than 9 months of the year. The tidal
floodplain covers an area of 216,000 ha (5.5% of the Delta. Salty soils are
found along the coast from Genh Hao
(Minh Hai Province) to Go Cong (Tien Giang Province), Can Duoc and Can Giuoc
(Long An Province). They cover an area of 809.000 ha
(21% of the Delta).
Acid sulphate soils
Nearly half of the Mekong Delta is susceptible to potential problems
of acid sulphate soils (ASS). ASS
are those areas where the oxidation of pyrite (iron sulphide)
and acidification process take place. . Pyrite is usually found in tidal
swamps, but it does not become a problem so long as the soil remains inundated.
Acid sulphate is formed when pyrite-rich sediments
are exposed to oxygen. ASS have low pH values and high
concentration of aluminum, iron, sulphate, and
hydrogen sulfide. The depth of the sulfuric horizon (pH below 3.5) is used to
characterize the soil acidity: severely acid soil where the scale is within the
upper 50 cm; moderately acid soil where the scale is between 50 and 80 cm, and
slightly acid soil where the scale is between 80 and 120 cm.
Drained ASS produce
sulfuric acid, which dilutes into surface water, brings down the soil pH to
below 4, attacks clay content of soils, subsequently release aluminum, which is
toxic to plant growth. The capillary process makes severely acid soils
unsuitable for agriculture.
Potential and actual
acid sulphate soils are pre sent in many parts of the
Mekong Delta covering a total area of 1,590,000 ha, mainly in the Dong Thap Muoi and Long Xuyen Quadrangle. Acid sulphate
soils in the Delta can be subdivided as follows:
Sulphate: found
in the Dong Thap Muoi and
Long Xuyen quadrangle, in low-lying areas along the Hau River and in parts of the lowlands between the Tien
and Hau rivers. This covers an area of 510,000 ha
(13% of the Delta). These soils have very high concentration of sulphates and low pH values ranging from2.26 to 3.54. Dong Thap Muoi closed floodplain
system affected by deep and prolonged inundation during the rainy season covers
an area of 414,400 ha (10.6% of the Delta) with high concentration of sulphates.
Salty sulphate: found in Ca Mau and along the
shores of the Gulf of Thailand. This subtype covers an area of 1,080,200 ha (28% of the Delta). Ha Tien open floodplain system is a relatively well-drained
area of 217,500 ha (5.6% of the Delta). Insufficient fresh water during the dry
season and presence of salt and sulphates in the soil
make the area marginal for agricultural use. The U Minh
Melaleuca forests of peat and sulphate
soil types cover an area of 189,400 ha (4.9% of the Delta).
Basin Development Plan
(BDP) Must
Embrace Programs to Support Salinity and Acidity Management in the Delta
It is crystal
clear that salinity and acidity management are vital issues facing the Delta.
They must be incorporated into the BDP. It boils down to one single factor that
adequate fresh water availability in the dry season will help to solve or
alleviate these two issues.
The salinity control
measures and other resource developments in the Delta are set out in the Master
Plan for the Mekong Delta (NEDECO 1993). Salinity control measures involving the
construction of dykes and canals focus on these smaller watercourses and affect
very large areas.
Acidity management is
critical to the Mekong Delta as population pressures and programs for agricultural expansion
add to intense conversion of acid sulphate soils,
mainly for rice production. Dong Thap Muoi or the Plain of Reeds has transformed with new
settlement and extensive reclamation. Farmers' experiences in cultivation
practices applied to acid sulphate soils produced
encouraging results. Dong Thap's rice production
amounted to 2.1 million tons in 1994, compared with 600,000 tons in 1980. The
government of Vietnam targets
to reclaim 101,000 hectares by the
year 2010, out of the remainder 120,000 hectares still uncultivated.
Here lays the
difference in approach to manage ASS entailed in this paper. As
a proposal elsewhere in this paper points to the conversion of deep ASS area
into multi-purpose reservoir to provide freshwater in the dry season, instead.
Extensive rely on leaching ASS would lead to environmental degradation.
Draining of such soils resulting in exposure of severe acid sulphate
soils, however, creates major problems for Dong Thap
itself and for downstream areas especially at the beginning of the rainy season
as acidic water is flushed down
towards the sea. The resulting acidity
transfers to surrounding land, contaminates surface water and becomes a threat
to aquatic ecosystems.
Summarily, management
of potential or actual ASS should involve both precautionary action and
curative or adaptive interventions where acidity has become a problem. In this
regard BDP for the Delta must stress on an
integrated management approach. BDP must
strike a balance between ASS treatment and environmental protection.
Furthermore, BDP for
the Delta must find ways to effectively deal with acid sulfate soils with
cursory research on alternative interdisciplinary approaches including the
anaerobic treatment process and sulfate burying such as creating multi-purpose
large-scale water reservoirs in the Delta's Dong Thap
and Long Xuyen Quadrangle to entrap silt buildup and
provide source of freshwater in the dry season. The hard fact is as long as
freshwater is available for cultivation, almost any types of ASS are manageable
for rice cultivation or other upland-type-crops planted on raised beds.
About the author: Ho Van Cao obtained his doctoral degree in Economics from Georgetown University, USA. He was a former Assistant
Minister of Finance and Government Commissioner of Industrial Development Bank
of South Vietnam. He was a member of the National Petroleum Board and Presidential
Cultural and Social Commission. Notably, he was an Administrative Chief of a
district peripheral to Dong Thap Muoi
(Plain of Reeds), worked and lived with the Mekong delta people whose bare
heels tarred with "phen" (sulphate soils). One of his pen name
is NGUON PHIEN (Pure Sulphate Nodule). In spite of
his pen name he is an advocate of any solution to solve the ASS (Acid Sulphate Soils) problems and hopefully to grow high-yield
rice on it, knowing that the current combination of century-old farming methods
with recent scientific researches on ASS are the only applications that one
could be content with. But his relentless motivation coupled with his
professional passion still drives him toward miraculous solutions of the
ASS-related problems.