Becoming the Shi Ma River by Jane T

becoming the shi ma river

Jane Tsong, Edna Robidas, Greg Dalton Landscape Architecture 512L/Methods and Applications in Landscape Architecture/ Fall 2012/ Cal Poly Pomona/ Weimin Li

NASA LANDSAT

contents 0 introduction/toward a landscape-based reorganisation of the city 1 process and methodology/ course description 2 regional context/ geomorphology, climate, threats to regional water quality 3 land use/ from dike pond systems to the pearl river delta economic zone 4 shi ma river/ three incarnations 5 inventory/ watershed and township boundaries, transportation, topology, land use, population, industry 6 pollutants/ distribution of water contaminants, list of pollutants 7 land units 8 design typologies/ creating a low impact infrastructure a approaches to urban agriculture/ tiered agriculture b dike pond systems/ branding local agricultural traditions c streets/ low impact infrastructure, regional identity d meanders/ oxbow treatment wetlands e zoning for high density development f green corridors 9 appendices/ bibliography, book reviews

introduction “Made in China.” Consumer electronics, footwear, clothing, plastics and toys cheaply produced in China fuel consumer lifestyles around the world. 18% of the goods Americans import ($399,361,900,000) originate in China. The dependence is mutual: of China’s top ten export destinations, US is the first, and accounts for 30% of volume. Leading this phenomenon have been cities in the Pearl River Delta Economic Zone whose spectacular growth and influence have been newsworthy for decades. 30% of all Chinese exports come from the Pearl River Delta Economic Zone. However, the spectacular success of the Pearl River Delta Economic Zone has come at a cost. Rapid changes in land use are decimating the natural resources. The quality of water in the Shi Ma River (石马江) exceeds class V- not fit for industrial or agricultural use. Yet water from this river is used to irrigate fields, threatening local food security, as well as the viability of centuries old sustainable agricultural model of Dike Pond Systems. Can the Shi Ma River one day be a demonstration that economic growth need not entail decimation of the natural resources upon which a region’s health depends?

/ a landscape-based reorganization of the city

A report by Greenpeace on Pearl River Delta water quality points out that end of pipe attempts at water treatment are too late. Nor can conventional wastewater treatment methods treat the countless variety of industrial pollutants present in local water. Advanced methods such as flocculation and precipitation of sludge which are increasingly used, can be effective. However, this technology is resource intensive and only defers the problem by creating sludge that needs to be disposed of as toxic waste or further processed for extraction. Urgently, we need to incentivize low impact production methods, including coaching by third parties to evaluate whether approaches to manufacturing that use less chemicals can be used. Third party water quality testing may be a way to hold individual polluters accountable. Most important of all, we need to create demand for sustainably manufactured products in export markets such as the United States. Supplementing these urgent efforts should be a landscape-based reorganization of the city. A low impact infrastructure can improve water quality and quality of life on a site level. Such interventions can buffer against flood, drought and subsidence on a regional level. Shanghai’s Houtan Park by Turenscape (2010) demonstrates how constructed wetlands can improve water quality from Class V to Class III at

a substantial savings from conventional treatment methods while providing cultural and ecological benefits. Recent developments in the greater Pearl River Delta include numerous initiatives to work toward greater integration of transportation, communications, energy, and water infrastructure among cities, including the 9 Pearl River Delta municipalities in Guangdong, as well as Hong Kong and Macau. With such large scale coordination of infrastructure in underway in the Pearl River Delta, we must urgently consider cost effective solutions to water pollution and flooding problems that have an effect on the long term health of the region.

C h

i n a Pe

GUANGDONG PROVINCE l R iv

Taiwan

Hong Kong

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GUANGDONG PROVINCE

Dongguan Shenzhen Hong Kong

PEARL RIVER DELTA 0

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The site is based in the province of Guangdong in the People’s Republic of China in the city of Dongguan. Dongguan is situated near the estuary of the Pearl River, a river whose watershed covers much of southern China.

geomorphology The Pearl River Delta is the confluence of three deltas: that of the North River, East River, and West River. These drain much of the southern portion of the People’s Republic of China. These rivers have surprisingly subtle gradients: the East River’s slope is a slight .26%, approximately tenfold that of the North and West Rivers. The Delta is surrounded by hills of approximately 500m above mean sea level, and the area within the delta is dotted with hills and terraces approximately 100-300m high, which were once islands. In general, the elevation of delta plains reflects the age of their reclamation, with “higher” plains representing older lands. Numerous tributaries wind through the plains. The natural tendency of delta streambeds to shift and meander due to sediment accretion has been temporarily arrested due to dike building, channelization, and other human manipulations.

20% of the silt naturally discharged by the rivers is deposited in the delta, while the rest runs into the sea. Historically, discharged sediment caused the delta to extend seaward at about 40m/yr. In the 1980s and 90s, however, the seaward extension was measured at 100+m/yr, much of which can be attributed to land reclamation and dike building. Reclamation of land creates extensive areas of lowlands vulnerable to both flooding and salt water intrusion. In recent decades, damming and channelization of rivers upstream prevents sediment reaching and regenerating low lying delta plains. Upstream land uses have a dramatic affect on lowlying lands. Removal of vegetation and proliferation of impermeable surfaces throughout newly urbanized lands prevents rainwaters from being stored and slowly released from soil. Instead, stormwaters flow quickly downstream where water levels rise quickly. All these factors compound the duration and severity of flooding.

/ a delicate balance in a great delta

Subsidence in the delta has been measured and may also become a significant factor in flooding. Subsidence in the Pearl River Delta is particularly pronounced in Guangzhou, Foshan and Dongguan, where urbanization happened particularly quickly. It is not clear what what the exact mechanism responsible for subsidence is. One researcher cites tectonic movement and compaction. In other deltas throughout the world, extraction of groundwater, mining for gas or petrochemicals is a common cause of subsidence. Because much of the delta is under 1m in elevation, small changes in sea level can have a destructive effect. Dongguan city, where the Shi Ma River is located, is slightly upstream of the main part of the delta at an elevation of 21 m. The Shi Ma River, a tributary of the East River, has a .61% average slope. Its natural course runs from south to north. Its total length is 73.5 km.

GOOGLE EARTH

land use

/ dike pond systems: a regional form of sustainable agriculture For centuries, people have sought to tame the shifting sediments and meandering channels of the delta tributaries through dike building and land reclamation. The intersection of delta ecology with cultivation of food crops has resulted in Dike Pond Systems, a regionally specific form of agriculture suited to low lying flood-prone lands. Dike Pond Systems integrate agriculture and aquaculture to minimize inputs while maximizing yields of fish and agricultural products.

collected to fertilize the mulberry plants.

In the most celebrated example of the dike pond system, mulberry for silk production is grown on the dikes. Droppings from silkworms are fed to fish. Fish droppings enrich pond sediments, which are then

During the Ming Dynasty, litchi, longan, and mulberry were grown in combination with fish. Sugar cane, banana, orange, litchi, and flowers, are now common. Each combination of crops has particular advantages. Banana and sugarcane can

Growing the two in combination enhances production of both crops. Silkworm droppings are said to have more nitrogen than livestock droppings. Droppings from 1 mu of mulberry trees feed fish in a 1 mu pond. Water is carried to crops planted along dikes through capillary action. This protects crops from both drought and flood. Excess water is easily stored in the ponds.

FAO Food and Agriculture Organization of the United Nations

Pond dike, Chang Chuang

Mulberry dike pond Mulberry and forest trees, Guangdong

AGRICULTURAL BYPRODUCTS & GRAIN

form layered systems in combination with poultry, melons, mushrooms, mulberry, carp. But flower dike ponds have been shown to have 6% greater fish output, and can be more lucrative than sugarcane or banana systems. Growing different fish species with different feeding ecologies in the same pond maximizes efficient use of resources, and allows harvesting in stages. Pigs, ducks, poultry can also contribute manure to the system. Whatever the particular combination chosen by a farmer for his circumstance, such integrated systems suggest alternatives to the overuse of chemical fertilizers elsewhere in the Delta.

Dike Pond Systems in the Pearl River Delta. Making clean water available for agriculture is a first step toward helping to ensure the future of this regional form of sustainable agriculture. Maintaining a Dike Pond System is labor intensive, and more lucrative jobs are attracting a younger generation elsewhere. However, creating cultural capital around this system can make it a valued part of society, bringing more prestige to farmers who continue this tradition. Dike Pond Systems should be promoted as part of the region’s transition toward sustainable land management and growth. Dike Pond Systems are part of the cultural heritage of the Pearl River Delta, an agricultural model that the international community can learn from.

With urbanization, the accumulation of organic pollutants, heavy metals and DDT in the soil are affecting the viability of

Guangdong fish ponds, piggery, bananas, mulberry, sugar cane

cow manure

snails

night seeds soil

night soil

POND

INPUTS

PIGLETS

PLANTS

pig manure

pigs

land crops

mud TABLE FISH

FINGERLINGS

PIGS

nutrient cycle

pig manure

PELLETS AQUATIC

OUTPUTS

chart content adapted from FAO Food and Agriculture Organization of the United Nations

Chart content adapted from FAO Food and Agriculture Organization of the United Nations

“The peasants of Shunde County estimate that 100,000 kg of pond mud are the equivalent of 50 kg of chemical fertilizers... The mud is better than chemical fertilizer because it is composed of about 5 percent organic matter, which the plants need. In addition, the mud acts as a weed killer, retards water evaporation, and maintains soil fertility for a longer period of time. The effects of the mud on the mulberry trees are particularly noticeable during the dry but still warm months of September and October.” (Lee 2004)

“Droppings from 1 mu of mulberry trees feed fish in a 1 mu pond.”(Lee 2004)

WEIMIN LI

land use

/ post-1978

GUANGDONG PROVINCE

THE NINE CITIES OF THE PEARL RIVER DELTA ECONOMIC ZONE

Guangzhou

Foshan

Huizhou

pop: 12,700,800

pop: 4,597,000

pop: 7,194,300

Zhaoqing

Dongguan

pop: 3,918,100

SPECIAL ECONOMIC ZONES In 1978, Deng Xiaoping’s Open Door Policy 1978 opened up the People’s Republic of China to economic liberalization. Aiming to attract foreign investment and technical expertise through tax incentives, Special Economic Zones were formed, several in close proximity to Hong Kong, Macau and Taiwan. The Pearl River Delta Economic Zone has been spectacularly successful among the Special Economic Zones. In the early 80s, it was the site of labor-intensive industry, which was supplanted by light industry, and after the 1990s, heavy industry, electronics, chemical products. The region, previously dominated by agriculture and fishing, is now the world’s most important producer of electronics, toys, textiles, and plastic products. 5% of the entire world’s goods are produced there, with total exports of US$289 billion (2001). The Pearl River Delta Economic Zone has only .4% of China’s land area and 3.5% of its population (2005), but accounts for 30% of its trade. Though early investment in the Pearl River Delta Economic Zone was dominated by foreign capital, the influence of Chinese investment is increasing. What’s more, there has been a realization that the rapid rate of growth cannot be sustained if it relies on an influx of cheap labor. Pearl River Delta cities now have the highest per capita GDPs in China, and the development of the Pearl River Delta Economic Zone as a significant consumer base appears to

pop: 8,220,000

Jiangmen

attest to the incredible economic success of the PRD economic zone.

Shenzhen

pop: 4,448,900

pop: 10,358,000

Zhongshan pop: 3,120,900

Zhuhai

HONG KONG AND THE PEARL RIVER DELTA ECONOMIC ZONES The fates of the Pearl River Delta Economic Zone and its more affluent neighbor, Hong Kong, have been integrally linked. Many industries relocated to the Pearl River Delta Economic Zone from Hong Kong because of low labor costs and regulatory advantages. Thus, while Hong Kong transformed into a cleaner service-based economy, cities in the Pearl River Delta Economic Zone became centers of manufacture. 90% of Hong Kong manufacturers have their production facilities in the Pearl River Delta Economic Zone, and more than 80% of PRD’s imports and exports are set up through Hong Kong. Yet there is a divide in resources and influence between Pearl River Delta Economic Zone cities and Hong Kong. Though Dongguan still has a high GPD per capita compared to the rest of the mainland, its per capita GDP is only half of Shenzhen and Guangzhou, and a quarter of that of Hong Kong.

pop: 1,560,200

1 2 0

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ThePEARL Pearl River Delta Economic Zone accounts for.... THE RIVER DELTA ACCOUNTS FOR....

8/100,000

7/1000

world population

world land area

all consumer products produced in the world (2001)

CHINA’S TOP TEN LOS ANGELES CUSTOMS DISTRICT China's Top Ten Export Destinations 2011 EXPORT DESTINATIONS 2011 2009 IMPORTS FROM CHINA percentage of volume exports Los Angeles Customs District 2009 Imports from China percentage of volume exports percentage of volume NOTE: LACD handles 40% of US-China trade exports Electrical Equipment & Components

Italy Singapore

FUTURE MEGACITY Together, Pearl River Delta Economic Zone cities constitute a megacity with higher population and density than Tokyo. Guangzhou and Shenzhen are already megacities (with populations over 10 million) and Dongguan may soon join their ranks. Increasingly efforts are underway to coordinate the transportation, water, energy, and communications infrastructure of the region.

6 0

2010 population statistics from Wikipedia“Pearl River Delta”

United Kingdom

Germany

20%

23%

India The Netherlands

Other

4% 3%

30% United States 5%

Iron & Steel Products Leather Goods Plastics

2% 2% 3%

Apparel (Knit) 5% South Korea

20% Computer Machinery

7% Apparel (Woven)

5% 6%

Japan

13%

uschina.org/statistics/tradetable.html

23%

Hong Kong

Furniture

6% Footwear

8% Toys

source: Growing Together p.40

LACD handles 40% of US/China Trade and includes LAX, Ports of LA, Long Beach, and Hueneme

the shi ma river

/ three incarnations

1960s

early

the Shi Ma River flows north, joining the East River.

a i M h S

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The highly polluted Shi Ma tributary is now diverted into canals before it meets the East River. A rubber dam directs the water toward two levels of treatment, including precipitated sludge, before it is released into the delta.

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8 pum ping s tations and 6 dam s m ove w ater ups tr eam thr ough the f or m er r iver bed

Despite such dramatic measures and expenditures, neither Hong Kong nor Dongguan is guaranteed clean water. At high tides, contaminated water reaches the intake for Hong Kong’s aqueduct. Greenpeace found 91-1000 times the acceptable level of E. coli in the new closed aqueduct, and 280 times the acceptable limit of mercury.

TO HONG KONG

Rubber dam diverts Shi Ma River from the East River Intake for Hong Kong moves upstream

PRELIMINARY TREATMENT

East Riv r e

D AQUEDUCT

ADDITIONAL TREATMENT BEFORE JOINING OCEAN

Shi

In Dongguan, water from the Shi Ma River is still unfit for either agricultural or industrial use. It has been said that 7 million people do not have access to clean drinking water, and 60% of people in Dongguan get drinking water from bottles.

Guangdong has taken numerous measures to safeguard cleanliness in the closely watched East River. Guangdong has planned to build 13 new wastewater treatment plants (to supplement 11 existing plants) on the East River. These plants are expected to treat 80% of sewage. However, they cannot be expected to treat the

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With continuing decline in the quality of water supplied to Hong Kong, Guangdong spent 4.7 billion yuan on infrastructural improvements completed in 2003, whose centerpiece is a new closed aqueduct for Hong Kong. In return, Hong Kong spends 2.4 billion HK$ (1-1.5% of its GDP) on its water supply contract from Guangdong.

ive aR

For about 4 decades (1960s to 2003), the bed of the Shi Ma River became a mere conduit to convey water from the East River southward to Hong Kong, a system of 6 dams and 8 pump stations forcing water upstream toward Hong Kong.

Numerous high polluting factories were shut down. Hog farming was banned from certain areas. Other polluting factories were relocated higher up in the same watershed (ensuring that the entire waterway is plagued by industrial pollution, instead of simply the lower half).

Because it supplies 70% of Hong Kong’s water, much international attention has focused on the East River. At one time, the Shi Ma tributary provided drinking water to the city of Hong Kong. With a decline in water quality, Hong Kong’s uptake was moved directly to the East River.

countless varieties of pollutants introduced into sewage systems by industrial dumping.

CANAL

Though they both get their water from the East River watershed, there are entirely separate water infrastructures supplying Hong Kong and Dongguan. Political and economic circumstances widen the divide between those who can get relatively clean water, and those who cannot.

TO HONG KONG

From the mid 1960s, Hong Kong uses the Shi Ma riverbed as a conduit to convey water south from the East River. 8 pump stations and 6 dams eventually complete a system which pumps water 46 m up in elevation toward Hong Kong. Water flows at a rate of 80 m3/sec during dry season. In periods of excess water, water is released to generate electricity.

1965

Guangdong completes the DongShen Water Supply Project (东深供水工程), a covered aqueduct meant to protect Hong Kong’s water, allowing the Shi Ma River to flow northward in its own bed again. Since runoff and effluent from the Shi Ma watershed is no longer diluted by water from the East River, flow is reduced to 3.6 m3/sec and water quality has climbed to Class V or worse (not fit for either agricultural or industrial use). During the dry season (when Shi Ma runoff is not diluted by precipitation), Shi Ma water is diverted into the Dongyin and Guancheng Canals. This protects water quality in the East River, which is under the international spotlight. Meanwhile, Shi Ma River water is treated through the precipitated sludge process before being released through Houmen gate into the Pearl River Delta.

2003

E a

s t

R i v e r

io s r ve m i D Da

l s

C a n a

M a

v e r GOOGLE EARTH

inventory TOWNSHIP AND WATERSHED BOUNDARIES Effective wastershed management is complicated by the fact that watershed boundaries do not coincide with political boundaries. The Shi Ma watershed lies within three separate cities: Dongguan, Huizhou and Shenzhen. Brown outlines indicate borders of Dongguan administrative townships.

Qiaotou 桥头镇

Changping 常平镇

Using catchment basin outlines provided by local governments, an area representing the Dongguan portion of the Shi Ma watershed was generated, and is represented in white. Areas in Dongguan not in the Shi Ma watershed are shown in gray.

Northwest of Dongguan, Tonghu watershed in Huizhou (494 km2) would normally drain into the East River. To protect the quality of water in the East River, the highly polluted Tonghu water is diverted into the Shi Ma and subsequently the Dongyin Canal.

Xiegang 谢岗镇

Zhangmutou 樟木头镇 Huangjiang 黄江镇

Because catchment data was only available to us for Dongguan, we did not include areas in Huizhou or Shenzhen in our analysis. On this map, portions of the Shi Ma watershed in Huizhou and Shenzhen are taken from a 2011 LA 512 analysis of the Shi Ma watershed by Haley, Montano, Russell, and Rodriguez. A significant tributary of the Shi Ma River is the Guanlan River, which originates in Shenzhen. The Guanlan watershed is 256 km2, 73% of which is in Shenzhen. The Guanlan River is well known to contribute heavily to the pollution load of the Shi Ma. Improving Shi Ma water quality cannot happen without the cooperation of Shenzhen.

Huizhou 惠州

Qingxi 清溪镇

Tangxia 塘厦镇

Fenggang 凤岗镇 ShenZhen 深圳

Township boundaries Shi Ma Watershed Outside of Shi Ma Watershed

WEIMIN LI

0 1.5 3

9 km

TRANSPORTATION

TOPOLOGY

Dongguan has one of Chinaâ&#x20AC;&#x2122;s highest road densities with total road mileage of 2438 mi within the territory. By the end of 2007 there was an average of 98 miles of class roads per hundred square kilometers. The transport network features a trans-city expressway and city highway.

The Shi Ma watershed is characterized by relatively flat plains surrounded by steep terrain which is largely undeveloped.

Impervious cover dominates urban and suburban areas. When rain falls on the city, it creates urban runoff that can cause flooding, erosion, and water pollution. Storm water runoff from parking lots, streets, and a building roofs are found to produce excess lead (Pb), zinc (Zn), manganese (Mn), and iron (Fe). During storms, rainwater flows across these impervious surfaces, mobilizing contaminants. The pollutants carried in runoff originate from a variety of urban and suburban no point sources. Oil, gasoline, and automotive fluids drip from vehicles onto roads and parking lots. Landscaping by homeowners, around businesses, and on public grounds contributes sediment, pesticides, fertilizers, and nutrients to runoff. (www.epa.gov/safewater/sourcewater/pubs/ fs_swpp_stormwater.pdf)

Roads Major roads

Low density= low slope

Railroads

0 1.5 3

High density= high slope

9 km

0 1 2

8 km

inventory WATER QUALITY CHEMICAL OXYGEN DEMAND AMMONIA NITROGEN While the Shima River is tested for 28 pollutants to determine which class it falls in according to National Standards, only three measures of water quality were released to us: Ammonia Nitrogen, Chemical Oxygen Demand (COD), and Phosphorus. This data shows that the Shi Ma River exceeds Class V standards, rendering it unfit for either industrial or agricultural use. According to Guangdong Water Resources and Electric Power Survey and Design Institute (2009), on the average, throughout its length, the river exceeds COD standards by 1.6 times, total phosphorus by 12.5 times and ammonia by 6.9 times. Pollution levels are so high that government goals for improving water quality are to bring tributaries up to Class V (neither suitable for agricultural nor industrial use) and and the main river to Class IV (suitable for agricultural and industrial use, but not suitable for human contact). Chemical Oxygen Demand is a measure of how much oxygen is needed to oxidize any quantity of organic compounds in water. Chemical Oxygen Demand in mg/l, 2005

Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

Ammonia Nitrogen in mg/l, 2005

Pollutant Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

0-25

Meets Class V standard (suitable for industrial or agricultural use, not suitable for human contact)

0-1.5

Meets EPA standard for aquatic life at 20째 at moderate Ph

25.0001-50

Exceeds Class V up to 2-fold

1.5-7.5

Exceeds standard up to 5-fold

50.0001-75

Exceeds Class V up to 3-fold

7.5-15

Exceeds standard up to 15-fold

75.0001-100

Exceeds Class V up to 4-fold

15+

Exceeds standard by more than 15-fold

100.0001-125

Exceeds Class V up to 5-fold

125+

Exceeds Class V more than 5-fold

1.5

9 km

1.5

9 km

FUNG GLOBAL INSTITUTE / FUNDATION METROPOLI

PHOSPHORUS Water Quality Goals for Shi Ma River and Tributaries

Source: Guangdong Water Resources and Electric Power Survey and Design Institute (2009)

Grade I/II (drinkable) Grade III (suitable for drinking, swimming) Grade IV (for industrial and agricultural use only, not suitable for human contact) Grade V (for agricultural and landscape use only) Exceeding Grade V (not suitable for either industrial or agricultural use) Data not available for smaller tributaries

Regional water quality context: major Pearl River Delta tributaries as they measure against the National Standards. Class I, II and III are considered to be drinkable and are indicated as blue and green. 1.5above 3 6 suitable 9 kmfor human contact) are shown as Class IV0and (not yellow, orange, and red. In recent decades, China has become the world’s most prolific producer of rare earth oxides. Rare earth oxides occur throughout the US, however, mining these oxides is a highly destructive chemicalintensive process, and therefore limited in scale in the US.

MAJOR SOURCES OF POLLUTION IN THE PEARL RIVER DELTA

Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

0- .20

Meets Class V standard (suitable for industrial or agricultural use, not suitable for human contact)

.20001-2

Exceeds Class V up to 10-fold

2.0001-4

Exceeds Class V up to 20-fold

4.0001-6

Exceeds Class V up to 20-fold

6.0001+

Exceeds Class V more than 20-fold

1.5

9 km

GLOBAL PRODUCTION RARE EARTH OXIDES 1950-2000 source: Wikipedia “Mountain Pass Rare Earth Production”

nates i m o d China rare earth global on ti produc

80 70

Production in kt

Phosphorus in mg/l, 2005

Industrial dumping Domestic Sewage Agriculture Rare Earth Mining Erosion (deforestation) Transportation The urban environment

60 50

China

40 30

USA

20 10 0 1950

Other 1960

1970

1980

1990

2000

pollutants PARTIAL LIST OF CONTAMINANTS Tens of thousands of chemicals are used by industry to create products we use every day: electronics, clothing, toys, plastics, pharmaceuticals. Though some of these chemicals have been tested for their effects on human health, we do not know their longterm effects on ourselves or on the ecosystems that surround us. A far greater number of chemicals commonly used in manufacturing have never been tested (Greenpeace 2010). Below is a very partial list of contaminants found by various studies to be present in Pearl River Delta water and sediments. Many persist

in the environment and accumulate in the food chain. Conventional wastewater treatment plants are not designed to remove such pollutants from our waste stream. National Standards which rate water quality in the Peopleâ&#x20AC;&#x2122;s Republic of China test water bodies for 28 pollutants. Officials have only released the figures for three contaminants of the Shi Ma River. In contrast, Hong Kong tests for 83 contaminants at the MukWu pumping station upstream of the cityâ&#x20AC;&#x2122;s intake, near the confluence of the Shi Ma and East Rivers.

TRANSPOR

MINING AGRICULTURE Typical byproducts of rare earth mining left in tailing ponds likely to cause contamination of water sources

tooth damage, bone disease, ulcers, arthritis, thyroid disease, and infertility

radioactive, and accumulates in bones, increases risk of cancer

Fluorine

Phosphorus promotes algal blooms, which consume oxygen as it decomposes, suffocating fish and shellfish populations

Carbon oxidizes into CO2, absorbs heat in the atmosphere, contributing to global warming

Nitrogen promotes algal blooms, which consume oxygen as it decomposes, suffocating fish and shellfish populations

Thorium

NH4-N Ammonium Nitrogen

Nitrogen

fertilizers promotes algal blooms, which consume oxygen as they decompose, suffocating fish and shellfish populations

HCH

fertilizers promotes

pesticides accumulates in

algal blooms, which consume oxygen as it decomposes, affecting fish and shellfish populations

sediment despite being banned in 1983 reproductive and neurotoxic impairments, various forms of HCH may be carcinogenic

Phosphorus

Hexachlorocyclohexanes

in warm temperatures, this turns into nitrates, which promote algal blooms, which consume oxygen as it decomposes, killing off fish and shellfish populations

Acids

such as oxalic, hydrochloric, or sulfuric acid, pumped through holes drilled into rocky mountainsides to extract ores lowered Ph of water can increase bioavailability of heavy metals and their accumulation in living organisms

DDT Dichlorodiphenyl trichloroethanes

pesticides accumulates in sediment despite being banned in 1983. Endocrine disruptor, with potential genotoxicity, bioaccumulates It breaks down into DDD and DDE, which is an antiandrogen

PAHs

Polycyclic aromatic hydrocarbons

from the incomplete combustion of petrochemicals accumulates in sediment 18 separate PAHs are registered with the Agency for Toxic Subtances and Disease Registry. As a group, PAHs are generally associated with birth defects, mutations, cancer, anxiety, depression, and developmental delays

ed t c e p s su ine r c o d n e ors t p u r s di

TBT

Butyltin compounds

biocide used in marine paints persists in environment, bioaccumulates causes immunosuppression and hearing damage in marine mammals, causes invertebrates to develop sex organs opposite of thier gender

used in metal alloys and as lubricant for drilling for oil or water

metal alloys, opacifier

Barium

RTATION INDUSTRY PCDF

Polychlorinated dibenzofurans

from vehicular emissions with leaded petrol Causes birth defects, mutations, and cancer, and have a high potential for bioaccumulation

PCDD

Polychlorinated dibenzo-p-dioxins “dioxins”

created in waste incineration, combustion and manufacture of PVC, bleaching of paper, vehicular emissions Bioaccumulates, may be carcinogenic, immunotoxin, causes birth defects in animals, persists in environment

PCBs

Polychlorinated biphenyls

insulation products in electrical equipment, combustion of chlorine-containing wastes, vehicular emissions endocrine disruptor, neurotoxin, carcinogen

2,4,6-TBP benzophenones 2,4,6- Tribromophenol wood

compounds that cure inks, images, and coatings, blocks UV light transmission though clear plastic packaging

preservative (anti fungal), emissions from vehicles using leaded petrol, used in creating flame retardantsneurotoxin, endocrine

a component of polycarbonate

such as Octyl phenol and nonyl phenol

used to create detergents, as additives to fuels, polymers, resins, and are used to make fragrances, chemicals, and fire retardant materials Persistent, bioaccumulative endocrine disruptor

TBBPA Tetrabromobisphenol-A

Brominated flame retardants endocrine disruptor, degrades into Bisphenol A

TEHP

bisphenol-A

alkyl phenols

Tris (2-ethylhexyl) phosphate

flame retardant and solvent Toxic to mammals, carcinogen

First used as an artificial estrogen for women and a growth enhancer for livestock, now used as a hardener in plastics. Endocrine disruptor. Impacts brain development, thyroid function of mammals and promotes growth of neuroblastoma cells

DEHP, DnBP

Phthalates

used to create flexible plastics toxic to reproductive development of mammals. Damages liver, kidney, lungs.

known ine r c o d n e ors t p u r s di

Zirconium

Soluble zirconium is readily taken up by aquatic plants

Mn Manganese

used in the manufacture of metal alloys, batteries, fertilizers neurotoxin, headaches, tremors, stiffness, impotence

Toxic effects on livers and kidneys of mammals. Endocrine disruptor.

disruptor. Evidence of toxicity to marine organisms, bioaccumulates. Evidence of disruption to fish fertility and reproductive success

If water soluble Barium compounds are formed and ingested, increased blood pressure, heart rhythm changes, changes in nerve reflexes, kidney and heart damage, swelling of brain and liver

Sulfur

a byproduct of coal burning sulfur dioxide, and sulfuric acid are byproducs of rare earth mining acid rain

Nickel

metal alloys allergic contact dermatitis can be caused by ingestion, carcinogen, interferes with absorption of essential minerals, accumulates in aquatic biota

dichloromethane Pb methylene chloride industrial solvent Possible carcinogen.

Prolonged skin contact can dissolve fatty tissue in the skin resulting in irritation or chemical burns. Metabolized by the body into carbon monoxide, leading to carbon monoxide poisoning

thioxanthones

compounds that induce polymerization used to manufacture chips and printed circuits May cause longterm effects in aquatic organisms at low concentrations. Though it is unregulated , the EPA considers it to have high aquatic toxicity

metals

Lead

lead-acid batteries damages nervous and reproductive systems, kidneys, impairs learning ability

Co Cobalt

used in manufacture of electronics high levels can bioaccumulate. many aquatic organisms are sensitive to even low concentrations

Cu Copper

bioaccumulates. toxic to many aquatic plants and animals, with effects at even very low levels. longterm exposure can cause liver and kidney damage in humans

Cd Cadmium heavy metal

As Arsenic

heavy metal

Be Beryllium

product of coal burning, also used in electronics possible carcinogen. According to World Health Organization, ‘there is no reliable data on the oral toxicity of beryllium in humans’

Hg Mercury heavy metal

can be d e c u d e Cr r Chromium ough used in metal thr ion t a alloys and l u c coatings, floc paints and dyes

if not processed, can turn into hexavalent chromium, which is toxic and causes mutations

Zinc

metal alloys, galvanizing, white pigment bioaccumulates. High doses can cause impaired immune responses, pancreatic damage, anemia, gastric erosion

land use typologies dike pond systems: branding local agricultural traditions Morus alba Mulberry

Nelumbo nucifera Water lotus

Agriculture is the cultural heart of the region. Cultural and agricultural policy can ensure Dike Pond Systems’ smooth transition into a contemporary world. Retaining the presence of sustainable agriculture in a rapidly industrializing region provides an urgent incentive to clean up pollutants that threaten the region. Agricultural extension programs, research institutions, scientists, and government might seek collaborative ways to support Dike Pond farmers while researching bioremediation in contaminated ponds. Taking advantage of international interest in traditional methods of sustainable agriculture, partnerships with international agricultural internship systems like WWOOF (Worldwide Opportunities on Organic Farms) can provide additional income to farmers. Most importantly, the interest of international interns can enhance the cultural status of sustainable agriculture, encouraging a younger generation to continue and innovate within this tradition.

东

桑莞基鱼塘

A sustainable agriculture self-guided walking tour takes young urbanites and tourists on a tour of the agricultural heritage of the region. The walking tour route also functions as an unusual public space in a society in which public spaces are few and restricted in scope.

FAO Food and Agriculture Organization of the United Nations GOOGLEEARTH

land use typologies streets: low impact infrastructure, regional identity n or e f tio al llec sw o fc

bi o ro o

Scirpus lacustris

Miscanthus sinensis

Tabermontanus bulrush

Chinese Silvergrass

Dongguan is serviced by a combined sewer system, where storm drains and sewage share the same below-ground infrastructure. This system was not meant to handle the capacity that rapid development has incurred. During the rainy season, domestic and industrial sewage overflow into the river. Such deluges also strain the capacity of wastewater treatment plants. Dongguanâ&#x20AC;&#x2122;s numerous streets with wide parkways offer an opportunity to create an extensive above-ground bioswale network that can absorb much excess stormwater. Separating stormwater from sewage will keep domestic and industrial effluent out of streams, while providing important flood control benefits downstream. Such a low impact drainage infrastructure offers esthetic, pollutant and flood control benefits at relatively low cost. Because the tributary network is so vast, there are relatively frequent opportunities to link such a bioswale network with tributaries.

r o f e l wa off s o bi t run ee Plants may be chosen to enhance regional r t s cultural identity (see overleaf). Such a low impact infrastructure is an opportunity for bioremediation. This will require regular harvesting and processing of contaminated biomass. A bioswale between sidewalk and buildings absorbs stormwater from rooftops. Meanwhile another bioswale between the road and sidewalk absorbs pollutants and runoff from roadways. Plants can be chosen for their cultural meanings, creating a low impact infrastructure that adds to a sense of cultural identity.

Dongguan’s numerous streets with wide parkways offer an opportunity to create an extensive above-ground bioswale network that absorbs excess stormwater, while separating stormwater from below-ground sewage. Because the tributary network is so vast, there are relatively frequent opportunities to link such a bioswale network with tributaries. GOOGLEEARTH

combined sewer system rainy season scenario

storm water exceeds capacity of system, causing sewage to overflow into river

sewage

water sewage and storm

storm water combined with sewage exceeds capacity of wastewater treatment plants

wherever possible, stormwater is absorbed by a network of bioswales. excess runs into tributaries, not into underground pipes

separated sewer system rainy season scenario aboveground bioswales slow stormwater and collect nutrients and pollutants

sewage 12’

12’

50’

12’

stormwater only

12’

sewage only

er t at lan w p te nt as e w tm to rea t s

to local tributaries

storm water infiltration

groundwater infiltration

wetlands kidneys of the earth, soul of Dongguan

Low impact infrastructure is an opportunity to build regional identity

Scirpus lacustris

Nelumbo nucifera

According to some, Dongguan (东莞) may be named after a locally native reed, "guan" (莞). Tabermontanus bulrush once grew throughout Guangdong and was woven into mats.

For centuries throughout China and India, Lotus has been a buddhist symbol of purity rising from unclean waters. In the Pearl River Delta, lotus is an important plant used in the early stages of land reclamation, when fields are too still too saline for other crops.

syn: Schoenoplectus lacustris, Scirpus validus, Schoenoplectus tabernaemontani

Because it is used in Chinese medicine and its seeds, pods, roots in cooking, any use of this plant for heavy metal uptake should be labelled to prevent consumption.

东莞

Ni, Cr, Co, Zn, Mn, Pb, Cd, Cu, Hg, Fe victorian flora

Schoenoplectus tabernaemontani victorian flora

scirpus lacustris

Cd, Cu, Ammonia

oflickr 331128

Miscanthus

Nymphaea

Various species of Miscanthus are native to parts of East Asia. Some have been tested for bioremediation and for use as a biofuel.

Water Lily is unrelated to the lotus, but also has significance in Buddhist lore. Native and exotic species are both common in Guangdong.

Miscanthus condensatus has high salt tolerance.

Nymphaea violacea and spontanea have been tested for use in bioremediation.

The sterile hybrid Miscanthus giganteus produces biomass rapidly and is used for heat and electricity generation in Europe. It is being tested on a commercial basis in the US. Miscanthus biomass can supplement coal at in some coal burning plants without modification of the existing setup.

Though not the most efficient accumulator of hexavalent Chromium, Choo et al (2006) found that Nymphaea spontanea can be grown alongside fish and other crops without becoming a maintenance problem as other hyperaccumulators (duckweeds) do.

Use of metal accumulators as biofuels runs the risk of recontamination of the environment, so these two uses may not be compatible. Though both parents of Miscanthus giganteus are native to Asia, the hybrid, like any non-native plants used in the landscape, should be tested for detrimental environmental effects before widespread use.

Nymphaea nouchali wikipedia

U, Cr-6 , Th radionuclides wikipedia

zhangye chinadaily_com

horatziu1977

heavy metals, biofuel production

land use typologies meanders: oxbow treatment wetlands These former meanders have been converted into fish or irrigation ponds

Meander paths are a major feature of the flat plains of the Shi Ma watershed. Patterns of sediment accretion that attest to the ongoing process of meander formation can be clearly seen in satellite photos. River meanders have a natural tendency over time to become wider and wider, until meanders separate into â&#x20AC;&#x153;oxbow lakes.â&#x20AC;? Some meander paths in the Shi Ma watershed have been reclaimed for other uses. In other locations, humans attempt to preserve existing land uses by fighting erosion and dredging sediment. Patterns of sediment deposition that lead to formation of meanders are part of a natural cycle that cannot be permanently obstructed without continual inputs from humans.

Main flow diverted into treatment wetlands. Rainy season overflow prefers the main, straightened channel, because its slope is greater and unobstructed.

At the same time, the increased surface area of meanders offers opportunities for treatment wetlands that absorb and slow stormwater, remove pollutants, and improve flood control downstream. The main river channel can be graded with a low flow channel so that most dry season flow is forced into treatment wetlands. Because the slope and water speed of meanders will always be less than in a straightened stream, the treatment majority of wet season flowwetlands will have a natural tendency to keep to the main channel, which is relatively frictionless, steeper, and unobstructed.

amount of stormwater entering wetlands, if necessary. Sediment settling ponds are situated at the beginning of each wetland and can be cleaned out regularly. at entry to each

MEANDERS BECOME WET

wetland is a low tech diversion structure, weir and sediment settling basin

treatment wetlands Original zig zag meanders

Diversion walls and adjustable weirs are lowtech ways to further control the

These former meanders have been converted into fish or irrigation ponds

Main flow diverted into treatment wetlands. Rainy season overflow prefers the main, straightened channel, because its slope is greater and unobstructed.

GOOGLEEARTH

treatment wetlands

MEANDERS RECONNECTED TO FORM TREATMENT WETLANDS

TLANDS, WITH ADDITION OF A STRAIGHTENED CHANNEL

treatment wetlands

treatment wetlands treatment wetlands

at entry to each wetland is a low tech diversion structure, weir and sediment settling basin

ADDITION OF STRAIGHT CHANNEL

RIVER CHANNEL is graded to force mĂ¸st low flow into treatment wetland at entry to each wetland is a low tech diversion structure, weir and sediment settling basin

ADJUSTABLE WEIR allows low flow to pass underneath into oxbow wetland while limiting rainy season flow into wetland

During rainy season, flood water will tend to flow through the main straightened channel, because it is relatively frictionless and unobstructed, and its slope greater than the meanders. A low tech adjustable weir will help regulate water entry into wetland if necessary. SEDIMENT SETTLING BASIN widening of the channel forces sediment to settle

ADJUSTABLE WEIR allows a constant flow to pass underneath

OXBOW WETLAND

MAIN CHANNEL

treatment wetlands

Original zig zag meanders

SEDIMENT SETTLING BASIN

DRY SEASON

MAIN CHANNEL

treatment wetlands treatment wetlands

WET SEASON

MAIN CHANNEL

land use typologies zoning for high density industrial and residential uses Further development is expected in the Shi Ma River watershed. Though we cannot stop further development in the watershed, we can zone to restrict building to areas that are already urbanized. Mountainous areas are the source of clean water, and their preservation is necessary to ensure water quality. Concentrating like land uses together allows for cost effective infrastructure specific to land use types. It can allow for more effective monitoring of individual pollution sources, and solutions tailored to specific land use types. Opportunities that result from clustering residential and industrial uses densely are shown on these pages.

water from several rooftops collects in a common wetland

RESIDENTIAL

Clustering high density housing allows the efficient collection of rainwater from rooves into common wetlands parks, which can ease the burden on sewage infrastructure.

Collection of rooftop rain collection into common wetland parks ease the burden on sewage infrastructure

WEIMIN LI

diagram adapted from ABC Waters Design Guidelines

owly wetlands and sl by ed sh li po is water s drains e ground. Exces infiltrates into th k. bioswale networ into low impact

Real time data from pretreated industrial effluent made available on internet, tickerboards in public locations, and published in newspapers.

reuters.com

drpinna.com

so lar

rad

iat

ion

nytimes.com

INDUSTRIAL

Without effective monitoring of point source pollution, individual polluters are not held accountable for lack of action. Clustering industrial uses together makes more effective monitoring and centralized pollution-control infrastructure possible. In this scenario, sensors pick up real-time pollutant data from industrial effluent. The data is available on the internet, posted on electronic tickerboards, and published in newspapers.

distilled water for reuse

WEIMIN LI

Effluent then travels to a common collection basin, where further testing can take place. Evaporation, aided by solar radiation, distills clean water for reuse while concentrating pollutants for more efficient treatment and possible reharvesting of metals.

Evaporation, aided by solar gain, distills water to be reused, concentrating pollutants for more efficient treatment or reharvesting of metals

FLICKR/BEMYBUTTERFLY