95
8 Eutrophication in the Great Lakes of the Chinese Pacific Drainage Basin: Changes, Trends, and Management
of the local authority responsible for managing a lake depends on the lake’s size, location, and ownership. A Lake
Management Commission is usually established for lakes of
significant economic importance. Because flood controls,
environmental pollution, and the development and use of
natural resources are directed by different agencies, the Lake
Management Commissions play an important role in the coordination between these different agencies, accommodating
various needs and uses. When this coordination is inefficient
or fails, the signs of deterioration can often be seen at many
lake sites.
The changes in eutrophication conditions in Lake Tai
reflect a general trend of nutrient enrichment in large lakes
in the PDB. Chinese authorities have realized the seriousness of halting this continuous deterioration in water quality
and have established laws for controlling industrial effluents
and provided funding to study eutrophication issues. A case
in point is the action taken by NEPA, the major agency in
China, dealing with environmental and water quality issues.
This agency has conducted several national lake surveys to
better understand the extent of lake pollution problems and
has provided funds for treating eutrophication problems.
Lake Tai has also received funds from NEPA for its water
quality studies with additional funds from the Chinese Academy of Science, the Chinese Natural Science Foundation,
and Jiangsu Province. In addition to these efforts, Lake Chao
in Anhui Province has also received a sizable grant from
NEPA and Anhui Province to study and improve lake water
quality. However, water quality continues to worsen in the
lakes in the PDB and many have developed seasonal or regional anoxic conditions.
In May 2007, an algae outbreak sparked by unusually hot
weather overwhelmed a water filtration plant that supplies
Wuxi City on Lake Tai’s north shore, leaving more than 2
million people without drinking water for a week. This outbreak prompted Wuxi City and its Environmental Protection
Bureau to take the unusual action of forcing hundreds of
small chemical and manufacturing plants near Lake Tai to
close or relocate. They instituted strict controls on effluents
from the factories that were permitted to stay in order to cut
down on pollution and the massive influx of N and P. These
actions leveled off the continuing downturn of water quality
conditions in that lake (Stone 2011).
Industries are the primary sources of lake pollution in
the PDB since they contribute more than 75 % of the total
untreated run-off and have the greatest impact on lake quality. Industrial run-off also has the most severe impact on
aquatic environments. Monitoring and controlling industrial
pollution is NEPA’s responsibility; NEPA issues guidelines
for industrial effluents and assists the local EPA in monitoring run-off from factories. The day-to-day responsibility
for monitoring and controlling industrial pollution, however,
rests with the local EPA. The level of regional supervision
of polluted industries depends on those factories’ official
classification. For example, the provincial EPA supervises
the provincial industries, while the county EPA has authority with respect to county enterprises and factories. In general, the factories that have received national attention are
monitored carefully and have installed pollution devices to
meet the Chinese water quality standards. However, these
factories are in the clear minority. Despite the creation of national and regional environmental agencies in China, the development of major environmental laws and the creation of
an impressive network to enforce these regulations, most industrial wastes are not monitored and no routine lake survey
has been carried out for most lakes. Furthermore, because
many regional authorities (at both the county and municipal
levels) lack sufficient operating revenues, regional EPAs rely
heavily on the funds from pollution fines to operate. This dependency provides little incentive for regional authorities to
control industrial pollution and to reduce industrial run-off.
As a result, the decline of public waterways continues. Water
quality in most lakes in the PDB faces further deterioration.
8.4.2 Flood Control
water resource management and flood control are the two
major lake management activities carried out by the Ministry
of Water Resources. In order to control floods and maximize
the use of water resources, the Ministry of Water Resources
and the regional water authorities have installed weirs and
dams in most waterways and lake tributaries since the 1950s,
except in those lakes, such as Lakes Poyang and Dongting,
where the quantity of the water flowing in and out of the
lakes is so large that controls are impractical. The management of water quantity and levels in lakes, and decisions regarding opening and closing dams, are the responsibility of
water resources authorities. In most cases, the floodgates are
raised in winter to drain lake water and provide the capacity
needed to accommodate peak flow in spring and summer;
floodgates are closed for most of the rest of the year. There is
little or no water outflow in spring, summer, and fall except
where lake water levels become unsafely high. The construction of dams and weirs since the 1950s has reduced potential
damage to lowland areas in several major floods and has increased the use of lakes and waterways for other activities
such as irrigation and transportation.
However, the construction of dams and weirs for flood
control, while useful in other respects, has greatly affected
fisheries resources and aquatic life, especially those species,
which use riverine spawning grounds and live in the lakes.
Recruitment of these species in most lakes is impossible as
a result of dam construction and some carp and crab species have experienced noticeable population reduction. Fingerling and larval fish stocking programs are now the major
8 Eutrophication in the Great Lakes of the Chinese Pacific Drainage Basin: Changes, Trends, and Management
of the local authority responsible for managing a lake depends on the lake’s size, location, and ownership. A Lake
Management Commission is usually established for lakes of
significant economic importance. Because flood controls,
environmental pollution, and the development and use of
natural resources are directed by different agencies, the Lake
Management Commissions play an important role in the coordination between these different agencies, accommodating
various needs and uses. When this coordination is inefficient
or fails, the signs of deterioration can often be seen at many
lake sites.
The changes in eutrophication conditions in Lake Tai
reflect a general trend of nutrient enrichment in large lakes
in the PDB. Chinese authorities have realized the seriousness of halting this continuous deterioration in water quality
and have established laws for controlling industrial effluents
and provided funding to study eutrophication issues. A case
in point is the action taken by NEPA, the major agency in
China, dealing with environmental and water quality issues.
This agency has conducted several national lake surveys to
better understand the extent of lake pollution problems and
has provided funds for treating eutrophication problems.
Lake Tai has also received funds from NEPA for its water
quality studies with additional funds from the Chinese Academy of Science, the Chinese Natural Science Foundation,
and Jiangsu Province. In addition to these efforts, Lake Chao
in Anhui Province has also received a sizable grant from
NEPA and Anhui Province to study and improve lake water
quality. However, water quality continues to worsen in the
lakes in the PDB and many have developed seasonal or regional anoxic conditions.
In May 2007, an algae outbreak sparked by unusually hot
weather overwhelmed a water filtration plant that supplies
Wuxi City on Lake Tai’s north shore, leaving more than 2
million people without drinking water for a week. This outbreak prompted Wuxi City and its Environmental Protection
Bureau to take the unusual action of forcing hundreds of
small chemical and manufacturing plants near Lake Tai to
close or relocate. They instituted strict controls on effluents
from the factories that were permitted to stay in order to cut
down on pollution and the massive influx of N and P. These
actions leveled off the continuing downturn of water quality
conditions in that lake (Stone 2011).
Industries are the primary sources of lake pollution in
the PDB since they contribute more than 75 % of the total
untreated run-off and have the greatest impact on lake quality. Industrial run-off also has the most severe impact on
aquatic environments. Monitoring and controlling industrial
pollution is NEPA’s responsibility; NEPA issues guidelines
for industrial effluents and assists the local EPA in monitoring run-off from factories. The day-to-day responsibility
for monitoring and controlling industrial pollution, however,
rests with the local EPA. The level of regional supervision
of polluted industries depends on those factories’ official
classification. For example, the provincial EPA supervises
the provincial industries, while the county EPA has authority with respect to county enterprises and factories. In general, the factories that have received national attention are
monitored carefully and have installed pollution devices to
meet the Chinese water quality standards. However, these
factories are in the clear minority. Despite the creation of national and regional environmental agencies in China, the development of major environmental laws and the creation of
an impressive network to enforce these regulations, most industrial wastes are not monitored and no routine lake survey
has been carried out for most lakes. Furthermore, because
many regional authorities (at both the county and municipal
levels) lack sufficient operating revenues, regional EPAs rely
heavily on the funds from pollution fines to operate. This dependency provides little incentive for regional authorities to
control industrial pollution and to reduce industrial run-off.
As a result, the decline of public waterways continues. Water
quality in most lakes in the PDB faces further deterioration.
8.4.2 Flood Control
water resource management and flood control are the two
major lake management activities carried out by the Ministry
of Water Resources. In order to control floods and maximize
the use of water resources, the Ministry of Water Resources
and the regional water authorities have installed weirs and
dams in most waterways and lake tributaries since the 1950s,
except in those lakes, such as Lakes Poyang and Dongting,
where the quantity of the water flowing in and out of the
lakes is so large that controls are impractical. The management of water quantity and levels in lakes, and decisions regarding opening and closing dams, are the responsibility of
water resources authorities. In most cases, the floodgates are
raised in winter to drain lake water and provide the capacity
needed to accommodate peak flow in spring and summer;
floodgates are closed for most of the rest of the year. There is
little or no water outflow in spring, summer, and fall except
where lake water levels become unsafely high. The construction of dams and weirs since the 1950s has reduced potential
damage to lowland areas in several major floods and has increased the use of lakes and waterways for other activities
such as irrigation and transportation.
However, the construction of dams and weirs for flood
control, while useful in other respects, has greatly affected
fisheries resources and aquatic life, especially those species,
which use riverine spawning grounds and live in the lakes.
Recruitment of these species in most lakes is impossible as
a result of dam construction and some carp and crab species have experienced noticeable population reduction. Fingerling and larval fish stocking programs are now the major