As early as 2004, due to strong opposition,
a proposal to develop the Nu River was delayed.
In early 2011, Chinese energy officials started to
mention development of the Nu River again,
but many experts objected. What are the reasons?
The Nu River is the only river in southwest China
with no dams, remaining a pristine ecological basin.
Together with Jinsha River and Lancang River,
the Nu River flows into Northwest Rift Valley,
from Qinghai-Tibet Plateau, thus creating
the world famous Three Parallel River landscape.
China』s Energy Bureau said it will develop Nu River,
and two retired scientists became restless.
In early 2011, Xu Daoyi, 77, and Sun Wenpeng, 78,
made a trip to conduct a survey on the Nu River area.
They pointed out that it is a great risk to build a dam
from an academic point of view, and considering all
complex geological environment and potential risks.
Chief Engineer of Sichuan Geology and Mineral』s
Bureau, Fan Xiao, told NTD, "The Nu River
is a very important transitional area between
the Eurasian and Indian Ocean plate,
just like the site of Japan』s recent earthquake,
between the Eurasian and Pacific Ocean plate.
Geologically, Nu River is near such a critical area.”
Research of the cross sections of Nu River Valley
found that there are 2-3 100 meter-wide breakages,
and over 30 smaller breakages. The section
with breakages runs about 400-1000m. It would be
very dangerous to construct a hydropower station
on the Nu River, says Sun Wenpeng.
Building a dam across the fractured zone is like
“building a dam across scissors』 blades”.
Although many experts agreed with them,
those in favor of building the dam said,
“There are many good dams along the river”,
“If the slope is stabilized, it should be effective.”
Fan Xiao said, the dam site and stability alone
aren't enough. The Nu River is in its seismic active
period, which should be taken into consideration.
Fan: “This is western Yunnan』s earthquake zone.
Many earthquakes of magnitude 7+ took place here.
Not long ago, an earthquake occurred due to
the Da-Ying River. This indicates that the entire
western Yunnan, including Nu River fracture,
is in a very active quake zone.”
Xu Daoyi and Sun Wenpeng also believed that
if an earthquake occurs, a collapsed upstream dam
could cause the other downstream dams to collapse.
Billions of cubic meters of debris, along the straight,
steep and narrow river would destroy the entire valley.
Fan believes that even if one builds a stable dam,
in case of a geological disaster, the surrounding
environment would be damaged immensely.
Fan: “They didn』t consider what would happen
to the area if a major earthquake should occur.
Due to high mountains and the gorges in the region,
even if the dam stands solidly, a huge earthquake
could induce disasters like landslides and mudslides.”
Even without considering all geological hazards,
modern science has realized that the reservoir itself
could also induce large-scale landslides in the area.
In turn, they could result in a high reservoir surge
that would threaten and impact the dam』s safety.
