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UN says China dams threaten water supplies to Mekong delta farmers
Vietnam Net 27/05/2009
http://english.vietnamnet.vn/reports/2009/05/849858/
VietNamNet Bridge Chinas construction of big hydro-power dams on
the Mekong River will be a great threat to the future of the river, a
significant water source for Southeast Asia, a United Nations report
said. Senior experts analysed the impacts on Vietnams Mekong River
Delta.
According to AP, China has built eight dams on the upper Mekong River
in Yunnan province. It recently finished the construction of the 292m
Xiaowan Dam, the worlds highest arch dam. The UN report released on
May 21 said that this dams capacity is equivalent to the entire
capacity of all reservoirs in Southeast Asia.
At the same time, Laos has begun to build 23 dams on the lower Mekong
River and its estuaries. This work is scheduled to finish in 2010.
The UN report stated that just the Xiaowan Dam alone can reduce the
water volume and the running speed of water, lowering water quality
and biodiversity in the Mekong River, which runs through six
countries.
Young Woo Park, the UN Environment Programme director, warned the six
governments to pay attention to the Mekong River, otherwise the future
water resources of these countries may be threatened.
Ky Quang Vinh, director of the HCM City-based Centre for Observation
of Natural Resources and the Environment, analysed the impacts of
Chinese dams on the lower section of the Mekong River, particularly
the Mekong River Delta of Vietnam.
He said: Dams of 15m height are quite big. It is unimaginable that the
Xiaowant Dam is 292m. This dam may help draw water to serve some dry
regions in China or to produce hydro-power. However, a vast area will
be submerged, which will cause changes in the eco-system in this
region. Some flora and fauna species may disappear, including rare
ones.
The Mekong River is being cut into pieces, not only by the Xiaowan Dam
in China, but dams in other countries like Laos, Thailand and
Cambodia. These Southeast Asian countries plan to build 11 hydro-power
dams on the main branch of the Mekong River. These dams will prevent
flows of fish and cause disorder in the river, threatening the lives
of millions of people who live along the river.
Chinas dams on the upper Mekong River have caused serious
environmental problems for the lower section like in Myanmar, northern
Thailand and northern Laos. The decline of fish reserves and the
change of the water level will make the lives of local people harder.
The Mekong River ranks behind only the Amazon in diversity of aquatic
animals. It is one of the richest baskets of fresh-water fish in the
world, which supports over 60 million people. It is estimated that the
river yields income of more than $3 billion a year.
The construction of dams on the main stem of the river will threaten
the extinction of rare animals, for example the Irrawaddy dolphin,
Mekong giant catfish and others. Eco-regression will be a global
disaster.
In Vietnam, there will be eco-changes. A huge volume of fish often
moves to the Cuu Long River (the section of Mekong River in Vietnam)
during the flood season. Dams prevent the flow of fish to Vietnam. In
addition, ecological balance will shift. Perhaps the Mekong River
Delta will not have a flood season anymore because there will not be
enough water.
More dangerously, the river will be seriously short of fresh water. It
happened in the recent dry season and will be more serious in the
coming years. The water volume has also decreased. Measurements
conducted last October showed that the flow was 28,000 cu.m per second
while it was 40,000 cu.m in the past.
In the 2009 winter-spring crop, the flow of the Tien and Hau Rivers
was only 1,600 cu.m per second, 100 cu.m per second less than
required. In some areas in the lower section of the Cuu Long River,
farmers lacked fresh water for irrigation. In coastal areas of Tien
Giang, Ben Tre, Tra Vinh, Soc Trang, Bac Lieu and Ca Mau, salt water
encroached 70km into the mainland.
In Vi Thanh town, Tien Giang province, for the first time the local
people had to use salt water for 3-4 days continuously because tap
water providers didnt know that their sources of water were
contaminated with salt water.
Prof. Ngo Dinh Tuan, chairman of the Institute for Southeast Asian
Water Resources and Environments Scientific Council, said:
In the 1950s, China announced its strategy to move water from the
south to the north. Since then they have constructed many dams on the
Mekong River. These dams initially serve hydro-power production but
according to many experts, they will serve to transfer water from the
Mekong River to the Yangzi River and then to the dry northern region
of China.
Other countries like Laos, Cambodia and Thailand are also building
dams on the river. It is estimated that around 20 dams will be built
on the river and these dams will greatly influence Vietnam, at the
lower section of the Mekong River.
If China builds dams to serve power production, the first impact would
be a remarkable reduction of aquatic resources and the volume of
alluvium in the Mekong River Delta, resulting in landslides to balance
the alluvial volume. It would be very dangerous for people who live in
the lower section.
If China builds dams to transfer water from the Mekong River to the
northern region, it would be very dangerous because the water volume
going down to the lower section would be reduced considerably.
Some institutions have been established to deal with these problems,
for example the Mekong River Committee of Vietnam and the
International Mekong River Committee, which groups up Vietnam, Laos,
Cambodia and Thailand. However, the role of these institutions is
modest.
Anyways, the Mekong River Committee of Vietnam partly contributes to
prevent adverse impacts on the lower section of the Mekong River. We
have to take initiative in joining voices with the world in preventing
countries on the upper part of the river from overexploiting water
resources. We have to accept the construction of dams to produce
hydroelectricity but we have to protest the transfer of water from the
river to other regions, otherwise the impacts would be very serious,
especially when Vietnam has to suffer from impacts of climate changes.
We need a national strategy on this issue. I think we have to build
doors at the estuaries of nine branches of the Mekong River in Vietnam
to prevent the encroachment of salt water. We also have to build
reservoirs to stock up on water for the dry season.
This is a big issue that the government should address soon. It is not
only a problem for the Cuu Long River, but the Red River as well,
because China has also built dams on the upper Red River. |
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