FIDIC 2005 CONFERENCE, WORKSHOP 7: Sustainable Municipal Infrastructure
CASE STUDY: A SCIENTIFIC PERSPECTIVE OF DEVELOPMENT
The Future of Sewage Treatment in the Shenzhen River Watershed
Shenzhen Association of Consulting Engineers
Yi Yan, Zhang Yifan，Huang Gu
What is a Scientific Perspective of Development?
Since the start of China’s reform and open policy in 1980, dramatic achievements have arisen in the Chinese
economy, with both industry and social welfare drastically improving across the entire country over the past
25 years. The increase in China’s GDP alone since 1980 clearly attests to the magnitude of these
achievements, from less than 500 million RMB in 1980 to over 13 trillion RMB in 2004, with an average
rate of growth reaching 9% each year. However, this growth has relied heavily on the development and
exploitation of natural resources, with much less consideration given to environmental protection and the
recycling of resources. Although China’s GDP accounted for only 4% of the world total in 2004, the country
ranked first as the world’s largest consumer of steel, and second as a consumer of oil. In the same year, China
also consumed 13% of all electricity and 31% of all coal produced globally. Clearly, if proactive measures
are not adopted, this pattern of economic growth will surely bring adverse consequences for the future.
China’s long-term economic growth and issues of sustainable development were substantial topics of
discussion at the Third Meeting of the 16th National People’s Congress of the Communist Party of China.
From this meeting emerged the theory called “a Scientific Perspective of Development”. This theory is based
on the aims of improving human welfare while maintaining a sustainable and comprehensive view of
development that can be applied to both rural and urban regions with great importance also given to critical
issues such as natural resources and the environment.
The theory behind this scientific perspective of development emerges from an overall analysis of the history
of development. The path of economic development can, in general, be traced through three stages. The early
beginnings of the Industrial Revolution through to the middle of the 20th century can be viewed as economic
development’s first stage. The aims of this first period were predominantly the unbridled optimization of
GDP. The maximization of wealth and production, and the accumulation of capital, were the ultimate goals
of this period, with almost complete disregard for their consequences on the natural environment.
The second stage in the history of development arose from the merging of a growing social agenda with
economic development. The 1960s and 70s were a time for crises – global economic setbacks, resource
shortages, environmental destruction – all of which helped to create a collective consciousness about the
shortcomings inherent in the economic paradigm put forward in the first stage. This awareness led to
consideration not only for the development of the economy, but also for issues such as education,
employment, social security, and environmental protection. Since the 1980s, world population levels have
become increasingly precarious, with resources and the environment continuing to worsen. Exposure to
economic development’s darker side has spurred action in defense of the environment. Concern is rising
about the dangers of unsustainable development, and the future depends on engaging alternative paths. In
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April of 1987, the United Nations Commission on Environment and Development published the well-known
report “Our Common Future”, which outlined the scale of the challenges facing the human race, as well as
the future of the environment and the economy. The term “Sustainable Development” emerged to encompass
the basic guiding principles and policy recommendations that set the direction to what here is described as
the third stage of development. This third stage emphasizes that healthy economic development must
maintain a robust and sustainable ecosystem, establish fundamental policies for social justice, and promote
the self-determination of all peoples. Other aims include securing the provisions needed to meet basic human
needs, advocating the full personal development of each member of society, and safeguarding resources and
the environment so that the needs and interests of future generations will not be jeopardized.
The principles of sustainable development lie at the heart of the scientific perspective of development put
forward by the Chinese government. However, consideration has also been given to China’s present stage of
economic development, and the strategy needed to establish the path and pattern for China’s future. Seven
basic principles are advocated in this scientific perspective of development. First, and most importantly, is
the need to continue building the economy. Measures to regulate the rate of growth and the quality of the
economy can help optimize the existing economic infrastructure and increase the range of development
beyond merely the economy。 The Second principle is to persist in coordinating economic and social
development, further emphasizing and accelerating the pace of the latter. The Third is to continue
coordinating urban and rural development, and undertake research to develop solutions for issues related to
farmers, rural areas, and the agricultural economy. The Fourth is to persist in harmonizing development
across the country, establishing pathways that promote interchange between China’s developing regions and
seizing opportunities for the exchange of local expertise across regional and national scales. The Fifth, is to
persevere in prioritizing sustainable development, maintaining a high regard for natural resources and the
environment. The Sixth is to continue with reforms and the open policy, further expanding openness to
countries and regions outside China. And finally, the Seventh aims to persist in considering human
well-being as a base premise in all directives, so as to meet the diverse needs of the population for its overall
development. Based on the manner in which these are realized, a workable scientific perspective of
development involves adhering to the aims of the “Five Comprehensive Plans”, call for diligence in
constructing the future economy and secure China’s progress to achieve balance both population and
economic development with the natural environment, with due attention given to ecological protection and
the sustainable use of resources.
Now to Shenzhen and its adoption of a Scientific Perspective of Development in issues related to the city’s
water issues.
Located on the southern coast of Guangdong Province at the mouth of the Pearl River Delta and linked with
Hong Kong to the south, Shenzhen has a total area of just over 1,950 square kilometres, with 396 square
kilometres dedicated to the Special Economic Zone. In May of 1980, Shenzhen was established as China’s
first Special Economic Zone.
Shenzhen’s rapid growth over the past 25 years can be attributed to the loosening of economic restrictions as
well as the diligence of those who have worked to develop the city. The original area of the city before 1980
was less than 3 square kilometers, with a population of less than 30 thousand residents. From a fishing
village with a GDP of less than 200 million RMB, the city has swelled into a modern metropolis with over
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10 million people, attesting to hundredfold increases across manifold economic indicators. In 2004,
Shenzhen’s GDP reached US$41.35 billion, ranking fifth amongst the GDPs of all the cities in China.
Average annual incomes reached US$7161 per person, leading the entire country with a basic standard of
living comparable to that found in other moderately developed countries. The total value of the city’s
production included 191.3 billion RMB for heavy-industrial output, and 325.7 billion RMB for new
high-technology production, with a 109 billion RMB investment in fixed assets, and 147.3 billion RMB for
imports and exports. Between 1980 and 2004, annual growth rates reached 28% for GDP, 38% for industrial
output, 35.1% for fixed assets, and 37.9% for import and exports.
Accompanying Shenzhen’s economic growth has been the role of direct government investment to boost the
overall function of the city. Fiscal revenues, income from land leasing, and loans to the government have, for
the most part, been invested into projects related to the national economy and public services, such as
transportation, postal services, telecommunications, environmental protection, and the construction of basic
facilities for social services. In 2004 alone, the Shenzhen government invested a total of 18.4 billion RMB
through 178 projects related to transportation, postal services and telecommunications, public health
education, agriculture, forests and irrigation, government infrastructure and social organizations. Presently,
the three pillars of the Shenzhen economy are high technology, finance, and logistics, with over eighty of all
“Fortune 500” enterprises having chosen Shenzhen as either their regional manufacturing, research and
development, or global supply center. In addition, Shenzhen has built a thorough sea, land, and air
infrastructure network which includes the world’s fourth largest container port accessing nearly all of the
world’s major shipping regions, an excellent road, highway, and rail transportation system, as well as China’s
fourth busiest airport, among the busiest fifty worldwide.
However, 25 years of rapid development have consumed the territory’s resources and their potential for use
by future generations, highlighting the conflict and constraints between resources, environment, population
growth, and demands for basic infrastructure. Presently, the Shenzhen Special Economic Zone has a
population density averaging over 10 thousand people per square kilometer, creating a serious test for the
city government in its provision for infrastructure and basic services such as transportation, water supply,
health and education facilities, etc. The result has been a sharp rise in costs that have impacted the city’s
entire economy. If this development precedent is continued, a steady rise in economic performance will be
increasingly difficult to sustain. Equilibrium between development and the carrying-capacity of the natural
environment will become an even more serious challenge for Shenzhen. Under these circumstances, a
scientific perspective of development can help to counter the momentum of the city’s previous development
precedents towards engaging alternative strategies.
In the conflict between the rapid pace of economic development and the limited carrying capacity of the
resources needed to sustain it, water resources are particularly critical for Shenzhen. Shenzhen is one of the
seven cities in China suffering from the most severe water shortages. Average water consumption in the city
is approaching 1.9 billion cubic metres per year. For every 187 cubic metres of water consumed per person
(based on a population of 10 million), only 45 cubic metres are available from local sources, creating a need
for the city to import 58% of its water demand from outside the city boundaries. Water pollution and the
overall condition of the city’s water resources are worsening, and all rivers within the urbanized areas are
foul. Surface water quality has deteriorated to Level V, and the water quality of Shenzhen Bay continues to
be as low as Level III, worse nearer to the shore with a Level IV. The concentration of organics in the water
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at the mouth of the Pearl River Delta has increased by three times over the past twenty years, and red tides
are now a frequent occurrence. The reasons for this are many, including insufficient wastewater facilities,
poorly installed pipelines that result in the mixing of sewage flows with rainfall runoff, insufficient sewage
treatment plants and sewer networks, as well as discharge loads that exceed the natural capacity to inherently
ameliorate pollution. Although investment in water resources protection and pollution control by the
Shenzhen government has increased with year, the rate of development and population growth are
confounding the pace of pollution control, increasingly worsening the condition of Shenzhen’s aquatic and
marine ecosystems. For example, in 2004, the average amount of sewage produced daily was 21.6 million
tons, far greater than the total treatment capacity of 13.4 million tons per day. In an effort to abide to the
principles of a scientific perspective of development, Shenzhen is making ambitious plans for sustainable
sewage treatment in the Shenzhen River watershed to overcome these shortcomings.
The critical shortage in Shenzhen’s water supply, along with the worsening of Shenzhen’s overall water
resources, endangers the future of social and economic development in the city. In light of these risks, the
Shenzhen government is giving great importance to the city’s water resources and ecological inventory as an
impetus for sustainable development.
Recently, the municipal government invited reputable water resource management experts to participate in
the initial planning and layout of the sewage treatment infrastructure for the Shenzhen River watershed. The
following is an outline of the six major points in the layout and planning of the Shenzhen River watershed:
(i) existing conditions of aquatic and marine environments
(ii) treatment methodology
(iii) sewage collection and treatment schemes
(iv) plans to convert wastewater into a usable resource
(v) work schedule for the planning and execution of project proposals, and
(vi) options for financing.
The overall layout of the sewage system across the Shenzhen watershed is the most important component of
the city’s entire sewage treatment scheme and protection measure for the city’s overall water resources.
Planning for this system is currently underway with substantial completion expected by 2010, and final
completion by 2020. The scope of planning covers the entire Shenzhen River watershed, in the east from
Wutong Shan, to the west at the Pearl River Delta, from the north at Niuweiling, Jigong Shan, and the
Yangtai hills, to the south along Shenzhen Bay and the New Territories in neighboring Hong Kong, including
the Shenzhen River and its main tributary, the Liantang River. The total area of this watershed is 348.56
square kilometers, occupying 17.8% of the total city area, with a population of 2,654,000 residents,
approximately 40% of the city total. This area was the earliest to be developed and is the city’s most mature
district. Presently, water pollution in the Shenzhen River watershed has a high rate of non-compliance for
municipal water quality standards such as five day BOD, COD, pH, and sulphides. Deficiencies in the
sewage treatment system frequently result in the failure to intercept all sewage flows, the disorderly
management of silt and sludge in the rivers and bay, the need to supplement the water supply, as well as other
management shortcomings. The problem is exacerbated by the fact that this area of Shenzhen, accounting for
only one-fifth of the entire city area, is forced to endure half of the city’s entire pollution load, with a sewage
discharge rate reaching 1.15 million tons per day.
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In 2000, Stockholm Resolution put forward the following points: first that regions and cities with water
shortages should be encouraged to collect, reuse, and circulate their sewage and wastewater; and second, that
cities having sustainable development agendas should store rainwater, giving high priority to the reuse of
circulated water and nutrients in the city. Under these guidelines, which apply to Shenzhen with its chronic
water shortage, the approach to treating pollution should engage ecology to remediate rivers and treat
pollution, thereby fulfilling a prime objective of converting waste into a resource.
The aims of sewage management in the Shenzhen River watershed include the interception of pollutant flows,
treatment of wastewater, prevention of contamination in water bodies, and protection of the aquatic and
marine ecosystems of the city. Where the pollution load entering the Pearl River Delta and Shenzhen Bay
exceeds their inherent carrying capacity for natural amelioration, this overall approach to pollution treatment
serves to reduce the amount of pollution entering receiving water bodies, improve the treatment rate and
effluent standard from treatment plants, and at the same time restore and safeguard the ecological integrity of
rivers and coastal wetlands. The proposals for sewage treatment in the Shenzhen River watershed puts forth
the following four objectives based on the scientific perspective of development and the sustainable
treatment of sewage: 1) control pollutants at their source; 2) intercept divert sewage to limit discharges;
3) reuse treated sewage; and 4) find opportunities to use treated wastewater to alleviate local water
shortages. This approach manifests the ideas of sustainable development and an economy that incorporates
recycling.
Controlling pollution at source relates to the interception of contaminated flows from the drains of
individual dwellings, housing estates, and sewage overflow pipes, in a measure to rectify disorderly and
harmful wastewater discharges. At present, every district government and water resource management group
in Shenzhen, along with every housing estate management unit, has taken action to control flows and divert
contaminated runoff for treatment.
The control of contamination at the source of pollution is part of an initiative to reduce discharges by
separating sewage flows from rainfall runoff. In addition to intercepting waste at its sources, there is also a
need to divert rogue sewage flows before they enter protected water bodies like the Shenzhen River.
Intercepting and diverting contamination is achieved by seizing sewage flows before they enter the main
north-south trunk storm sewer serving the watershed of the Shenzhen River and its tributaries. The
interception and diversion of unregulated sewage discharges away from rainfall runoff flows and towards
treatment plants is expected to result in the collection of 90 to 95% of all sewage flows in the Shenzhen
River watershed.
Limiting discharge refers to controlling the amount and quality of effluent discharged. Water conservation
is an effective way to reduce the quantity of sewage that is produced and subsequently discharged into the
receiving environment. The quality of the remaining wastewater to be treated in municipal facilities must
strictly adhere to national standards prior to their direct discharge into the municipal sewer network. By
lowering the amount of water needed for industry through conservation and recycling, it is possible to reduce
the costs per unit of production, which in the larger scheme will have a positive impact on the city’s overall
GDP. At the same time, it is necessary to improve the performance of sewage treatment plants to control the
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pollutant load entering the city’s water bodies.
The reuse of treated water refers to the transformation of sewage into a resource. Sewage is highly
available in large reliable quantities that are easy to obtain for use in applications that do not require potable
water. With respect to Shenzhen, this type of use is less expensive than the desalination of seawater or the
channeling of water over long distances from outside the city.
Ecological water management involves using treated sewage or treated effluent to restore and rebuild the
city’s damaged aquatic and marine environments. In particular, this water can be used to supplement
freshwater flows into Shenzhen Bay, to help suppress the upstream reach of tides and benefit the mangroves
and other living organisms, while reversing the damage already done to the Bay. After the eight rivers
flowing into Shenzhen Bay, including the Shenzhen River, meet the intended water quality targets, the
amount of freshwater entering the bay will play a very important role in restoring and maintaining ecological
balance. As a result, this principle is essential towards improving the water quality in Shenzhen’s aquatic and
marine environments.
The next major point related to the layout and planning of the Shenzhen River watershed deals with sewage
collection and processing, which is the most important link in the system. It is estimated that the sewage
generated in the Shenzhen River watershed will reach 2 million cubic metres per day by 2010, and 2.65
million cubic metres per day by 2020. The planning scheme for the treatment of sewage flows within the
watershed can be divided into nine systems, each corresponding to and centered around a specific sewage
treatment plant (the locations of which are shown in Figure 1). The watershed is currently served the four
sewage works found at Luohu, Binhe, Shekou, and Nanshan, which will be boosted by the five proposed
plants for Futian, Xili, Caopu, Pudixia, and Shawan. The anticipated sewage treatment capacity by 2020 is
expected to reach 2.65 million cubic metres per day. At the same time, new construction will correspondingly
enhance the city’s ability to prevent the mixing of sewage with runoff, as well as increase the overall rate of
treatment. Intercepted sewage flows will be effectively treated prior to their release into the river or sea.
The watershed employs comprehensive control systems that prevent the mixing of runoff with sewage, to
establish two general flow streams. In addition to sewage diversion, a city-wide pollution control process
will be implemented to install measures to capture one-third of the total runoff arising from the initial stages
of a rainfall event. Particularly important is that this rainwater be diverted through dedicated storm sewers
into retention and settling ponds, thereby alleviating the pressure to quickly transfer and treat sewage across
large distances. Every sewage plant within its range of service must build systems to increase its ability to
intercept contamination. Emphasis should be given to install storage facilities that regulate flows at times
when they exceed the loading capacity of the plant. Sludge from sewage plants will be treated through sludge
digesters built outside the Special Economic Zone.
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Table 1: Statistics for the Nine Existing and Proposed Sewage Treatment Plants in the Shenzhen River
Watershed
Sewage Plant
Existing
Plants
Shekou
Binhe
Luohu
Nanshan
Current
Operating
Capacity
（1000 m3/d）
30
300
350
736
Proposed
Plants
Futian
Xili
Caopu
Budixia
Shawan
/
/
/
/
/
Expanded/Proposed
Operating Capacity
（1000 m3/d）
Treatment Technique
80
400
to be upgraded
656
800
600
100
250
80
60
Existing Plants
Proposed Plants
Existing plants, such as those at Luohu and Binhe, primarily serve the main sewage flows coming from areas
surrounding the Shenzhen River. The plant at Shekou serves the area around Shenzhen Bay, and the one at
Nanshan is a large-scale plant mainly servicing Nanshan District (except the Shekou and the Xili
subdistricts). Owing to the fact that the sewage collection network is incomplete, the four existing sewage
plants are all operating below their designed sewage treatment capacities. The four plants at Luohu, Shekou,
Binhai, and Nanshan are all to be upgraded or expanded by 2020 to improve their standards. Technology
upgrades are planned for all plants, and although the scale of treatment at the Luohu plant will remain
unchanged, those at Shekou and Binhai are to be expanded to process 80,000 m3/day and 400,000 m3/day
respectively. The plans to upgrade the Nanshan treatment plant involve building a new addition to increase
its capacity to 736,000 m3/day. At the same time, the network of sewers will be upgraded and optimized to
sufficiently deliver sewage volumes that fully utilize the design capacities of the plants.
The treatment capacities for the five proposed plants at Futian, Xili, Caopu, Pudixia, and Shawan are shown
in Table 1. Of these, the Futian sewage plant will integrate capped treatment chambers on which a green-roof
park space wil be built that can serve as a viewing platform for bird watching over the coastal mangroves.
The Xili treatment plant will mostly treat water from the catchment area for the Xili reservoir as well as
sewage from the subdistrict of Shenzhen University. The water treated in this plant will be used for landscape
irrigation and other related municipal purposes. The Caopu sewage works, mainly serving Bujizhen, will also
be capped to reduce odor problems. The Budixia sewage plant will also mainly serve Bujizhen. The Shawan
treatment plant will primarily serve the lower reaches of the Shawan River.
All five of the new sewage treatment plants will incorporate 3-stage standard sewage treatment processes.
Next is the idea of converting sewage into a usable resource. Based on the wish to collect, reuse, and
re-circulate sewage water, the final use of treated sewage from each plant will depend on factors that take
into consideration location, the distribution of existing water resources, as well as the condition and quality
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of influents and effluents. Among these is the plant at Shawan, which will utilize a three-stage treatment
process to produce effluent that can be safely discharged to the nearby Shawan River. The plant at Luohu is
also to become a three-stage system, with its treated effluent used to boost the flows in the Shenzhen River
and benefit the river ecosystem. The treated effluent from the other three-stage plants will include that from
the Binhe plant, also used to supplement water in the Shenzhen River as well as serve the water features at
Lizhi Park, and the effluent from the Futian plant to be used to augment flows in the Xinshou, Fengtang, and
Xiaosha Rivers, as well as Shenzhen Bay. After sterilization, the treated effluent can be used to irrigate green
spaces, wash streets, or used in other municipal applications. Effluent from the three-stage plant at Xili will
be used to replenish water in the Sha River, which will also help to remediate the river ecology. After
sterilization, water from Xili will also be used for municipal purposes. Treated effluent from the Nanshan
treatment plant will be used to supplement the water needs of local parks, other non-potable municipal water
needs, as well as a nearby power plant.
The schedule for the execution and completion of the proposed projects estimates that all proposals will be
completed in the next three years. Planning for the nine treatment systems in the watershed will be executed
separately. The five proposed treatment plants as well as the diversion pipe network from the Buji River to
the Futian Treatment plant will be built forthwith, with the preceding period used to prepare project proposal
documents, feasibility studies, environmental impact assessments, preliminary project designs, construction
drawings, and bids from construction companies. Action for these preliminary stages was started at the
beginning of 2005, with total completion of plans expected by the beginning of 2006. Construction for each
project will mostly be carried out from the beginning of 2006 to the end of 2007, with final completion
estimated before 2008.
The total capital investment for all of these plans is expected to reach 4 billion RMB, which includes costs
for constructing and upgrading treatment plants, as well as for laying out new and upgrading existing sewer
lines. Part of the expenses arising from the construction of other related facilities, as well as the demolition,
relocation, and compensation of those who will be displaced, are also covered in this cost. The initial stage of
investment will be entirely funded by the government. It is also possible, based on previous experience in the
operation of basic infrastructure, that Shenzhen will adopt other forms of financing, such as through direct
loans from the World Bank to cover part of the capital costs. The city also has the option to obtain direct
investment for construction and operating costs by putting these facilities on the market, using BOT, TOT, or
PPP, etc.
Overall, the expansion of the sewage works across the Shenzhen River watershed will result in a significant
reduction in pollution, as well as the optimization of the city’s water supply and reuse of resources, come
together to set a local precedent that demonstrates the principles defining a scientific perspective of
development. Initiatives such as these will play an increasingly critical role to improve the urban and
ecological futures of Shenzhen.
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