China has stepped up the diversion of the Yangtze River to
dilute water polluted by blue-green algae in a lake that provides
drinking water for millions of people in the eastern Chinese city
of Wuxi, Jiangsu Province.
Water from the nation's longest river is flowing into Taihu Lake
at a rate of 150 cubic meters per second, up from the earlier 127
cubic meters per second, and the lake has received a total of 190
million cubic meters of Yangtze water since May 11, said the Taihu
Valley Administration under the Water Resources Ministry on
Thursday.
Wuxi, an economically dynamic city that administers six
districts in the city proper and two other small cities in the
outer areas, has a total population of 4.57 million and 2.32
million are in the city districts.
The affected population is mostly in the city districts,
accounting for 80 percent of the total, according to the local
government. The Taihu Valley Administration said Thursday that the
water supply from the Xidong Tap Water Company, which supplies 20
percent of the downtown urban population, was not affected.
But the water supply from the Xiaowanli Tap Water Company in
Wuxi has not resumed after supply was halted on May 22 when the
Taihu Lake started to stink with a blue-green algae bloom.
Citizens are complaining that the tap water is so putrid that
they can not wash with it.
"The tap water stinks and has a yellowish color, the whole
family has not taken a shower for two days," said Shi Xiuying, a
resident of Nanchang District.
The water level in three old wells in Shi's neighborhood is
dropping quickly as residents rush to stock up.
A large algae-choked area was visible near Nanquan, a major
water plant for Wuxi Tap Water Supply Company, where some workers
were trying to remove the algae on Thursday.
"The water quality is far beyond the limits of drinking water
treatment. It should be treated in sewage plants," said Zhou
Liusong, a worker at the Nanquan Water Plant.
The pollution had resulted in panic buying of bottled water and
bread in Wuxi, which had prompted the price of an 18-liter bottle
of water sold by street peddlers to rise from eight yuan to 50 yuan
by Wednesday night.
A downtown Walmart outlet strictly rationed sales of 500
milliliter bottles of water to a 24-bottle box per person.
"Bottled water is now sold out and we are transferring 1,000
boxes from nearby cities," said Shangguan Xiaoling, a member of
Walmart's staff, on Thursday.
"It is hard to say when the algae outbreak will clear, and we
are taking measures to reduce the impact," said Zhu Zhongxian, vice
secretary-general of the Wuxi municipal government, at a press
conference on Thursday.
In addition to diverting the Yangtze River water, the city
government is planning to artificially induce rain in the coming
days to dilute the polluted lake water.
The Wuxi Tap Water Supply Company is also pumping a large amount
of active carbon and potassium permanganate into the lake in an
attempt to purify the water.
Local authorities are closely monitoring supplies of bottled
water in 10 supermarkets and have allocated more bottled water from
neighboring cities of Suzhou, Changzhou, Nanjing and Shanghai.
The city's pricing bureau issued a circular on Wednesday to ban
water price hikes. Vendors who deliberately drive up water prices
may face fines of up to 300,000 yuan (39,200 U.S. dollars), it
said.
The local environmental agency is monitoring the water quality
around the clock.
Suzhou, a city neighboring Wuxi, was not affected even though it
also takes a domestic waster supply from Taihu Lake because the
parts of the lake that provided drinking water for the city were
not polluted, said Xia Jian, deputy director of the Suzhou
Municipal Water Resources Bureau.
Shanghai, about 128 km southeast of Wuxi, was not affected,
either, because it mainly uses the Huangpu River for drinking
water, which did not suffer the algae outbreak, according to local
water authorities.
Blue-green algae is a form of aquatic plant that occurs
naturally in rivers, lakes, damp soil, tree trunks, hot springs and
snow. "Bloom" is the common term used to describe an increase in
the number of algal cells to a point where they discolor the water,
form scum, produce unpleasant tastes and odors, affect shellfish
and fish populations or otherwise create a nuisance and seriously
reduce water quality.
Initial investigations show the water level of Taihu Lake is at
its lowest in 50 years this summer due to continuous high
temperatures and lack of rainfall, which have led to an excess of
nutrients in the water.
Taihu Lake is a scenic attraction famous for its aquatic life,
including whitebait, shrimps, lily and water chestnuts. But today
the lake is a malodorous shadow of its former self as a result of
pollution.
Qin Boqiang, research fellow of the Nanjing Institute of
Geography and Lakes Studies under the Chinese Academy of Sciences,
said that pollution from industry, agriculture and domestic waste
also caused an excess of nutrients in the water of the Taihu
Lake.
"The algae crisis is teaching us a serious lesson, and we must
earnestly solve pollution problems that are threatening the lake,"
he said.
(Xinhua News Agency June 1, 2007)