Becoming the Shi Ma River

becoming the shi ma river

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

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SA LA

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SAT

contents0 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 units8 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 developmentf green corridors

9 appendices/ bibliography, book reviews

“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 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.

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C h i n a

Hong Kong

Taiwan

GUANGDONG PROVINCEP e a r l R i v e r

P e a r l R i v e rGUANGDONG PROVINCE

0 1 2 0 2 4 0 3 6 0 4 8 km6 0

Hong Kong

Shenzhen

PEARL RIVER DELTA

Dongguan

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.

introduction / a landscape-based reorganization of the city

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.

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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.

geomorphology / a delicate balance in a great delta

land use / dike pond systems: a regional form of sustainable agriculture

collected to fertilize the mulberry plants.

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.

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

FAO

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anization o

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Natio

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Mulberry and forest trees, GuangdongMulberry dike pond

Pond dike, Chang Chuang

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.

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

land use / dike pond systems: a regional form of sustainable agriculture

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.

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

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.

AGRICULTURAL BYPRODUCTS &

GRAIN

PELLETS AQUATICPLANTS

pig manure

cowmanure

nightsoil

snails

POND pigmanure pigs land

crops

seedsnightsoil

PIGLETS

PIGS

mud

FINGERLINGSTABLE FISH

INPUTS

OUTPUTS

nutrient cycle

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)

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

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The Pearl River Delta Economic Zone accounts for....

all consumer products

produced in the world (2001)

5%

world land area

8/100,000 7/1000

world population

SPECIAL ECONOMIC ZONESIn 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

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

HONG KONG AND THE PEARL RIVER DELTA ECONOMIC ZONESThe 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.

FUTURE MEGACITYTogether, 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.

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Shenzhenpop: 10,358,000

Dongguanpop: 8,220,000

Huizhoupop: 4,597,000

Guangzhoupop: 12,700,800Foshan

pop: 7,194,300

Zhaoqingpop: 3,918,100

Jiangmenpop: 4,448,900

Zhongshanpop: 3,120,900

Zhuhaipop: 1,560,200

2010 population statistics from Wikipedia“Pearl River Delta”

GUANGDONG PROVINCE

THE PEARL RIVER DELTA ACCOUNTS FOR....

30%

23% 13%

7%

7%

5%

4%

4% 4% 3%

China's Top Ten Export Destinations 2011percentage of volume exports

United States

Hong Kong Japan

South Korea

Germany

The Netherlands

India

United Kingdom

Singapore

Italy

uschina.org/statistics/tradetable.html

LOS ANGELES CUSTOMS DISTRICT 2009 IMPORTS FROM CHINApercentage of volume exports

CHINA’S TOP TEN EXPORT DESTINATIONS 2011percentage of volume exports

23%

20%

8% 6%

6%

5%

5%

3%

2%

2%

20%

Los Angeles Customs District 2009 Imports from China NOTE: LACD handles 40% of US-China trade

Electrical Equipment & Components

Computer Machinery

Toys Footwear

Furniture

Apparel (Woven)

Apparel (Knit)

Plastics

Leather Goods

Iron & Steel Products

Other

source: Growing Together p.40

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

Hueneme

THE NINE CITIES OF THE PEARL RIVER DELTA ECONOMIC ZONE

land use / post-1978

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.

the shi ma river/ three incarnations

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.

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.

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.

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.

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

early1960sthe Shi Ma River flows north,

joining the East River.

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.

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

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).

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.

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.

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.

S

hi M

a R

iver

E a s t R ive r

PRELIMINARY TREATMENT

Rubber dam diverts Shi Ma River from the East River

Intake for Hong Kong moves upstream

ADDITIONAL TREATMENTBEFORE JOINING OCEAN

Eas t R iver

East Rive r

8 pumping s ta t ions and 6 damsmove water ups t ream through the former r iverbed

CO

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UC

T

TO HONG KONG

TO HONG KONG

CA

NA

LS

S

hi

Ma

Riv

er

1965

2003

GO

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TH

E a s t R i v e r

Sh

i

Ma

R

iv

er

C a n a l s

D i v e r s i o n

D a m

Qiaotou

桥头镇

Changping

常平镇Xiegang

谢岗镇

Huangjiang

黄江镇

Tangxia

塘厦镇

Zhangmutou 樟木头镇

Qingxi

清溪镇

Fenggang

凤岗镇

Huizhou

惠州

ShenZhen深圳

0 3 6 9 km1.5

Shi Ma Watershed

Outside of Shi Ma Watershed

Township boundaries

inventoryEffective 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.

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.

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.

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.

TOWNSHIP AND WATERSHED BOUNDARIES

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High density= high slope

Low density= low slope

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Major roads

Railroads

Roads

TRANSPORTATION TOPOLOGYDongguan has one of China’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.

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)

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

0 3 6 9 km1.5 0 3 6 9 km1.5 0 3 6 9 km1.5

125+

100.0001-125

75.0001-100

50.0001-75

25.0001-50

0-25

Exceeds Class V more than 5-fold

Exceeds Class V up to 5-fold




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

Chemical Oxygen Demand in mg/l, 2005 Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

15+

7.5-15

1.5-7.5

0-1.5

Exceeds standard by more than 15-fold

Exceeds standard up to 15-fold


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

Ammonia Nitrogen in mg/l, 2005 Pollutant Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

6.0001+

4.0001-6

2.0001-4

.20001-2

0- .20






Phosphorus in mg/l, 2005 Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

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.

inventoryWATER QUALITY CHEMICAL OXYGEN DEMAND AMMONIA NITROGEN

0 3 6 9 km1.5 0 3 6 9 km1.5 0 3 6 9 km1.5

125+

100.0001-125

75.0001-100

50.0001-75

25.0001-50

0-25







Chemical Oxygen Demand in mg/l, 2005 Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

15+

7.5-15

1.5-7.5

0-1.5

Exceeds standard by more than 15-fold



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

Ammonia Nitrogen in mg/l, 2005 Pollutant Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

6.0001+

4.0001-6

2.0001-4

.20001-2

0- .20






Phosphorus in mg/l, 2005 Figures from Guangdong Water Resources and Electric Power Survey and Design Institute, 2009

FUN

G G

LOB

AL IN

STITUTE

/ FUN

DA

TION

ME

TRO

POLI

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. Class IV and above (not suitable for human contact) are shown as yellow, orange, and red.

Pro

duct

ion

in k

t

1950 1960 1970 1980 1990 2000

80

70

60

50

40

30

20

10

0

source: Wikipedia “Mountain Pass Rare Earth Production”

GLOBAL PRODUCTIONRARE EARTH OXIDES 1950-2000

China dominat

es

global rare

earth

production

China

USA

Other

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 chemical-intensive process, and therefore limited in scale in the US.

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Water Quality Goals for Shi Ma River and TributariesSource: Guangdong Water Resources and Electric Power Survey and Design Institute (2009)

Exceeding Grade V (not suitable for either industrial or agricultural use)

Grade V (for agricultural and landscape use only)

Grade IV (for industrial and agricultural use only, not suitable for human contact)

Grade III (suitable for drinking, swimming)

Grade I/II (drinkable)

Data not available for smaller tributaries

Industrial dumpingDomestic SewageAgricultureRare Earth MiningErosion (deforestation)Transportation The urban environment

MAJOR SOURCES OF POLLUTION IN THE PEARL RIVER DELTA

PHOSPHORUS

AGRICULTUREMINING

INDUSTRY

NNitrogen

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

PPhosphorus

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

PAHsPolycyclic 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

DDTDichlorodiphenyl trichloroethanes

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

HCHHexachlorocyclohexanes

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

TBTButyltin compounds

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

PCDDPolychlorinated 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

PCDFPolychlorinated dibenzofurans

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

PCBsPolychlorinated biphenyls

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

TBBPATetrabromobisphenol-A

Brominated flame retardantsendocrine disruptor, degrades into Bisphenol A

alkyl phenolssuch 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

DEHP, DnBPPhthalates

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

bisphenol-Aa component of polycarbonateFirst 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

TEHPTris (2-ethylhexyl) phosphate

flame retardant and solventToxic to mammals, carcinogen

2,4,6-TBP2,4,6- Tribromophenol wood preservative (anti fungal), emissions from vehicles using leaded petrol, used in creating flame retardantsneurotoxin, endocrine disruptor. Evidence of toxicity to marine organisms, bioaccumulates. Evidence of disruption to fish fertility and reproductive success

dichloromethanemethylene 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

CoCobalt

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

MnManganese

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

thioxanthonescompounds that induce polymerizationused to manufacture chips and printed circuitsMay cause longterm effects in aquatic organisms at low concentrations. Though it is unregulated , the EPA considers it to have high aquatic toxicity

benzophenonescompounds that cure inks, images, and coatings, blocks UV light transmission though clear plastic packagingToxic effects on livers and kidneys of mammals. Endocrine disruptor.

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

NiNickel

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

Chromium

used in metal alloys and coatings, paints and dyesif not processed, can turn into hexavalent chromium, which is toxic and causes mutations

PbLead

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

ZnZinc

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

SSulfur

a byproduct of coal burning

sulfur dioxide, and sulfuric acid are byproducs of rare earth mining acid rain

ZrZirconium

metal alloys, opacifierSoluble zirconium is readily taken up by aquatic plants

BaBarium

used in metal alloys and as lubricant for drilling for oil or waterIf 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 Be

Beryllium

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

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

ThThoriumradioactive, and accumulates in bones, increases risk of cancer

NH4-NAmmonium Nitrogenin warm temperatures, this turns into nitrates, which promote algal blooms, which consume oxygen as it decomposes, killing off fish and shellfish populations

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

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

Typical byproducts of rare earth mining left in tailing pondslikely to cause contamination of water sources

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

Acidssuch 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

TRANSPORTATION

known

endocrine

disruptors

suspected

endocrine

disruptors

metals

can be

reduced

through

flocculation

Cd

As

Hg

Cadmiumheavy metal

Arsenicheavy metal

Mercuryheavy metal

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

pollutants 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 People’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 city’s intake, near the confluence of the Shi Ma and East Rivers.

PARTIAL LIST OF CONTAMINANTS

AGRICULTUREMINING

INDUSTRY

NNitrogen

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

PPhosphorus

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

PAHsPolycyclic 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

DDTDichlorodiphenyl trichloroethanes

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

HCHHexachlorocyclohexanes

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

TBTButyltin compounds

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

PCDDPolychlorinated 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

PCDFPolychlorinated dibenzofurans

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

PCBsPolychlorinated biphenyls

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

TBBPATetrabromobisphenol-A

Brominated flame retardantsendocrine disruptor, degrades into Bisphenol A

alkyl phenolssuch 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

DEHP, DnBPPhthalates

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

bisphenol-Aa component of polycarbonateFirst 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

TEHPTris (2-ethylhexyl) phosphate

flame retardant and solventToxic to mammals, carcinogen

2,4,6-TBP2,4,6- Tribromophenol wood preservative (anti fungal), emissions from vehicles using leaded petrol, used in creating flame retardantsneurotoxin, endocrine disruptor. Evidence of toxicity to marine organisms, bioaccumulates. Evidence of disruption to fish fertility and reproductive success

dichloromethanemethylene 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

CoCobalt

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

MnManganese

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

thioxanthonescompounds that induce polymerizationused to manufacture chips and printed circuitsMay cause longterm effects in aquatic organisms at low concentrations. Though it is unregulated , the EPA considers it to have high aquatic toxicity

benzophenonescompounds that cure inks, images, and coatings, blocks UV light transmission though clear plastic packagingToxic effects on livers and kidneys of mammals. Endocrine disruptor.

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

NiNickel

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

Chromium

used in metal alloys and coatings, paints and dyesif not processed, can turn into hexavalent chromium, which is toxic and causes mutations

PbLead

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

ZnZinc

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

SSulfur

a byproduct of coal burning

sulfur dioxide, and sulfuric acid are byproducs of rare earth mining acid rain

ZrZirconium

metal alloys, opacifierSoluble zirconium is readily taken up by aquatic plants

BaBarium

used in metal alloys and as lubricant for drilling for oil or waterIf 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 Be

Beryllium

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

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

ThThoriumradioactive, and accumulates in bones, increases risk of cancer

NH4-NAmmonium Nitrogenin warm temperatures, this turns into nitrates, which promote algal blooms, which consume oxygen as it decomposes, killing off fish and shellfish populations

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

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

Typical byproducts of rare earth mining left in tailing pondslikely to cause contamination of water sources

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

Acidssuch 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

TRANSPORTATION

known

endocrine

disruptors

suspected

endocrine

disruptors

metals

can be

reduced

through

flocculation

Cd

As

Hg

Cadmiumheavy metal

Arsenicheavy metal

Mercuryheavy metal

land use typologiesdike pond systems: branding local agricultural traditions

东莞桑

基鱼塘

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.

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.

Nelumbo nuciferaWater lotus

Morus albaMulberry

GO

OG

LEE

AR

TH

FAO

Foo

d and

Ag

riculture Org

anization o

f the United

Natio

ns

street runo�

roof collection

bioswale for

bioswale for

land use typologiesstreets: low impact infrastructure, regional identity

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 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.

Dongguan’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.

Plants may be chosen to enhance regional cultural identity (see overleaf). Such a low impact infrastructure is an opportunity for bioremediation. This will require regular harvesting and processing of contaminated biomass.

Miscanthus sinensisChinese Silvergrass

Scirpus lacustrisTabermontanus bulrush

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

storm water combined with sewage exceeds capacity of wastewater treatment plants

sewage

sewage

abovegroundbioswales slow stormwater and collect nutrients and pollutants

groundwater infiltration

combined sewer system

separated sewer system

rainy season scenario

rainy season scenario

stormwater only

sewage and stormwater

sewage only50’12’ 12’ 12’ 12’

wherever possible,

stormwater is absorbed

by a network of

bioswales. excess runs

into tributaries, not into

underground pipes

to wastew

ater

treatment plants

storm waterinfiltration

to local tributaries

GO

OG

LEE

AR

TH

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.

horatziu1977

Schoenoplectus tabernaemontanivictorian flora

Scirpus lacustris

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.

syn: Schoenoplectus lacustris, Scirpus validus,

Schoenoplectus tabernaemontani

Nelumbo nucifera

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.

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.

wikip

edia

Nymphaea

Water Lily is unrelated to the

lotus, but also has significance in

Buddhist lore. Native and exotic

species are both common in

Guangdong.

Nymphaea violacea and

spontanea have been tested for use

in bioremediation.

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.

Nym

phaea nouchali w

ikiped

ia

zhangye chinad

aily_com

Miscanthus

Various species of Miscanthus are

native to parts of East Asia. Some have

been tested for bioremediation and for

use as a biofuel.

Miscanthus condensatus has high salt

tolerance.

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.

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.

heavy metals, biofuel production

U, Cr-6 , Th radionuclides

oflickr 331128

Cd, Cu, Ammonia

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

东莞scirpus lacustris victorian flora

wetlands kidneys of the earth,soul of DongguanLow impact infrastructure is an opportunity to build regional identity

horatziu1977

Schoenoplectus tabernaemontanivictorian flora

Scirpus lacustris

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.

syn: Schoenoplectus lacustris, Scirpus validus,

Schoenoplectus tabernaemontani

Nelumbo nucifera

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.

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.

wikip

edia

Nymphaea

Water Lily is unrelated to the

lotus, but also has significance in

Buddhist lore. Native and exotic

species are both common in

Guangdong.

Nymphaea violacea and

spontanea have been tested for use

in bioremediation.

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.

Nym

phaea nouchali w

ikiped

ia

zhangye chinad

aily_com

Miscanthus

Various species of Miscanthus are

native to parts of East Asia. Some have

been tested for bioremediation and for

use as a biofuel.

Miscanthus condensatus has high salt

tolerance.

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.

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.

heavy metals, biofuel production

U, Cr-6 , Th radionuclides

oflickr 331128

Cd, Cu, Ammonia

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

东莞scirpus lacustris victorian flora

These former meanders have been converted into fish or irrigation ponds

at entry to eachwetland is a low techdiversion structure,weir and sediment settling basin

treatment wetlands

treatment wetlands

Original zig zag meanders


treatment wetlands

treatment wetlands

treatment wetlands

ADDITION OF STRAIGHT CHANNEL

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



treatment wetlands

treatment wetlands



treatment wetlands

treatment wetlands

treatment wetlands



land use typologies meanders: oxbow treatment wetlandsMeander 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 “oxbow lakes.”

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.

MEANDERS BECOME WETLANDS, WITH ADDITION OF A STRAIGHTENED CHANNEL

MEANDERS RECONNECTED TO FORM TREATMENT WETLANDS

GO

OG

LEE

AR

TH

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 majority of wet season flow will have a natural tendency to keep to the main channel, which is relatively frictionless, steeper, and unobstructed.

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

amount of stormwater entering wetlands, if necessary.

Sediment settling ponds are situated at the beginning of each wetland and can be cleaned out regularly.



treatment wetlands

treatment wetlands



treatment wetlands

treatment wetlands

treatment wetlands





treatment wetlands

treatment wetlands



treatment wetlands

treatment wetlands

treatment wetlands



MEANDERS BECOME WETLANDS, WITH ADDITION OF A STRAIGHTENED CHANNEL

MEANDERS RECONNECTED TO FORM TREATMENT WETLANDS

ADJUSTABLE WEIRallows low flowto pass underneathinto oxbowwetland whilelimiting rainy seasonflow into wetland

SEDIMENT SETTLING BASINwidening of the channel forces sediment to settle

OXBOWWETLAND

MAIN CHANNEL

MAIN CHANNEL

ADJUSTABLE WEIRallows a constant flow to pass underneath

SEDIMENT SETTLING BASIN OXBOW

WETLAND

RIVER CHANNELis graded to force møst low flowinto treatment wetland

MAIN CHANNEL

MAIN CHANNELDRY SEASON WET SEASON

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.

RESIDENTIAL

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.

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

water is polished by wetlands and slowly

infiltrates into the ground. Excess drains

into low impact bioswale network.

water from several rooftops collects in a common wetland

diag

ram ad

apted

from

AB

C W

aters Desig

n Guid

elines

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

WE

IMIN

LI

land use typologies zoning for high density industrial and residential uses

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

reuters.com drpinna.comnytimes.com

Real time data from pretreated industrial

effluent made available on internet, tickerboards in public locations, and

published in newspapers.

sola

r ra

diat

ion

distilled water for reuse

INDUSTRIALWithout 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.

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.

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Documents

Becoming the Shi Ma River