Abstract

Research of the environmental demise of Hong Kong’s Victoria Harbor concludes a collective source of problems at fault. Social constraints on the environmental sustainability of the Harbor include high population density, with the added problem of the perpetual influx of 10 million tourists annually, and the lack of proenvironmental behavior from the public. Studies show increasingly high concentrations of organic material and inorganic material in the waters of Victoria Harbor. Point and non-point source pollution invades the harbor through 17 sewage outfalls discharging 300 million tons of raw sewage, agricultural and urban runoff, and spillage. The polluted water has caused "red tides", affecting the local seafood economy, and the destruction of the biodiversity of Harbor aquatic life. Political constraints have come from the low emphasis towards proenvironmental laws and the lack of strict pollution enforcement. Opportunities of Harbor rehabilitation can be achieved through stronger environmental laws by increasing taxes and penalties and efforts by the government to increase environmental behavior and activities.

Introduction

Victoria Harbor once boasted pristine water sustaining productive coral reefs and mangrove stands. Fish and shellfish was an abundant commodity for fisherman. Whereas now, pier fishing yields a scrawny fish and a few strains of hepatitis. Swimmers dare not swim in the murky waters of the Harbor.

Land reclamation insidiously erodes the Harbor, progressively changing the landscape of Victoria Harbor into Victoria River. Extensive land reclamation and dredging around Victoria Harbor has radically altered Hong Kong's shoreline ecology, reducing the diversity of intertidal, seabed, and coral communities. Nearby sea grass beds and coral communities are harmed from settling clouds of silt stirred by dredging. As silt from dredging fills up the Harbor, it makes it more difficult for sea animals like the endangered Chinese pink dolphins to find food. (sun.simmons.edu/archives/vmsvax/0153.html)

Point source pollution is the main cause of damage to the Harbor. From toxic industrial wastes that include solvents, oils, acids, heavy metals, and other compounds to agricultural chemicals find their way into the waters of Victoria Harbor. Raw sewage from some 3.6 million people flows into Victoria Harbor, giving rise to severe effects from nutrient loading. Also, heavy shipping traffic in Victoria Harbor brings hydrocarbon pollution. The Hong Kong government estimates a discharge of 1.5 million cubic meters of industrial wastewater and domestic sewage each day. (www.cais.net/publish/stories/0596wat5.htm) Such pollution has resulted in irreparable damage to the biological environment, not to mention the effect on the living environment of humans.

While occasional typhoons may still be a hazard, the Harbor faces greater threats from man-made forces. The Harbor won’t return to its natural form but further damage can be reduced. The solution will require further knowledge of the technical and social aspects of the Harbor.

Social Aspects

The population of Hong Kong is 5,542,869, all bunched up in 990 sq. km. The size slightly less than six times the size of Washington, DC(www.theodora.com/hong_kong_geography.html). There are 5,598 people per square kilometer in Hong Kong contributing to vast amounts of waste in a small space. Inevitably and unfortunately the Harbor is heavily polluted. Space is scarce, and in a society where space is such a hot commodity, space equals money. Thus, Hong Kong gratefully adopts the concept of land reclamation.

Reclamation has played a major role in supporting urban growth. Filled land now accounts for more than 25 percent of the urban land area.(www.wri.org/wri/wr-96-97/ee_txt5.html) However, the consequence of reclamation is the negative effect on the natural environment of the Harbor. Observed by the scientific community and felt by local fishermen is the destruction of intertidal, seabed, and coral communities in the Harbor. Some reports also indicate restricted tidal flushing in the Harbor areas aggravating the already severe pollution problem.

Despite the negative impacts of reclamation, the government gives several reasons for its necessity (http://user.hk.linkage.net/~greenpow/essays/planning.htm):

1. To Accommodate Population Growth
1. Population growth is increasing, land must increase to support population
2. To Promote Hub Functions
1. Additional land is required for business, financial, trading, professional service fields, and the related development of new facilities for the tourists and business travellers.
3. Restructuring the Metro Area
1. To create a better organized city, to provide new transport links to relieve already congested corridors, and to address the shortfall in community and recreational facilities in these old areas, the provision of solution spaces on nearby reclamations is essential, especially to meet the rehousing needs of the residents who have long- standing socio-economic attachments to the areas.
4. New Transport and Infrastructure
1. Reclamations are required to provide land for the extension of our strategic road and rail network and associated facilities to meet raising demand
5. Cleaning Environmental Black Spots
1. Certain newly proposed reclamations have the potential of eliminating highly polluted 'black spots' in areas where the tidal flows are weak

Wastewater pollution coming from the sewage of 3.6 million people is also the byproduct of a densely populated area.(http://www.info.gov.hk/info/aaep.htm) Without pre installation of ample wastewater treatment systems, it has been difficult to maintain a viable way of controlling wastewater discharge as population increases. Fecal coliform levels from sewage contamination, for instance, are extremely high, and shellfish contaminated with human pathogens such as salmonellae, shigellas, and hepatitis viruses are common. The government, nonetheless, is responsible for controlling the influx of wastewater. This can be done through building more wastewater system infrastructure, funding through tax and stronger government enforcement of illegal discharge.

Currently, the public is charged for sewage services. Sewage services "involve the constructions of sewerage, sewage treatment and disposal facilities: and operation and maintenance of such facilities." Domestic households are charged HK$1.20 per cubic meter of water consumed.(EPD 1996) By implementing this sewerage charge, we can see that the Government adopts the polluter pays principle. To successfully maintain a sustainable environment for the Harbor, it is vital that the government emphasizes the contribution and responsibility of the public.

The public in turn has shown signs of increasing environmental awareness over the years. EPD has been operating pollution complaint hotlines since 1986. From 1994-1995, pollution complaints have risen over 19% to a total of 12,556. Complaints on water pollution have increased an astonishing 223%. However, this statistic may be misleading. Although there has been an increase of 223% in water pollution complaints, it only makes up for 0.4% of total complaints, despite the severe water condition.(EPD 1996) A reasonable explanation is that the public has become desensitized to the current water quality. Instead of treating Victoria Harbor as a Harbor in a severely polluted state, it has become the baseline for further comparisons of more severe accounts of pollution. One can only imagine the magnitude of the water pollution complaints.

"Environmental problems are primarily the result of maladaptive behavior rather than simply a consequence of technology."(Hamid & Cheng, 1995) The community’s attitude towards the environment directly correlates with their maladaptive behavior. A survey conducted in 1995, commissioned by the Environmental Campaign Committee(ECC) of HKEPD, was taken to gauge the changes in people’s environmental awareness and attitudes to the environment(EPD 1996). Survey findings show a slight positive increase in the overall attitude towards the environment. Seawater pollution makes up 10.2% of total responses to the question of what is Hong Kong’s most serious environmental pollution. 98.4% of the interviewees believe that individuals have a responsibility to protect the environment.(EPD 1996)

The public realizes the waters of Victoria Harbor are polluted so fishing has been at a minimum and it has been off limits to commercial fishing. However, it still effects the local fishing industry. Its polluted waters have drifted towards local fishing zones, affecting the population of the breeding fish. Desperate fishermen actually have spent their days illegally fishing Victoria Harbor; dangerously evading large boats in hope of catching any fish to sell. Unfortunately, the only fish caught are those specialized to the polluted area. Contaminated fish are thus leaked into the seafood market.

Public response to the destruction of Victoria Harbor’s natural environment has been positive to the support of stopping further destruction of the Harbor. However, it is overshadowed by the economic benefits of reclamation. Lobbyist environmental groups are prevalent in Hong Kong, but the lack of public participation still hinders the improvement of the Harbor. Plans to raise public awareness and concern as to the affects of reclamation and wastewater discharge are necessary for the advancement of any fight to save Victoria Harbor.

Technical Aspects

Victoria Harbor, located between Hong Kong Island and Kowloon, span an area of about 30 km². More than 4 million residents and 10 million annual visitors live around the central Harbor area.(Chan 1995) Despite a benefiting economy, the Harbor suffers severe pollution from the fast economic development and the dense population.

Victoria Harbor faces point source pollution, a direct source, and nonpoint source pollution, a diffuse source. Point source pollution, as cited in the direct dumping of raw sewage and industrial and domestic effluent, is flushed uncontrollably into Victoria Harbor. Approximately 300 million tons of untreated sewage is discharged in the Harbor through 17 sewage outfalls (see Fig.3).(Connell 1998) Nonpoint source pollution involves agricultural and urban runoffs, spillage, and foul sewer systems. The pollution from nonpoint sources is widespread and generally more difficult to control.

Contaminants, both organic and inorganic, discharge into the Harbor and sink within the marine sediment. The marine sediment acts like a reservoir entrapping the contaminants.(Y.S. Wong 1995) The sediment is mostly anaerobic and dark in color. It is important to realize the condition, as most pollution studies will retrieve samples from marine sediments.

Organic Pollutant

The Environmental Protection Department of Hong Kong has a monitoring program for persistent organic contaminants in sediments of Victoria Harbor. It is realized that organic compounds such as long-chain alkylbenzenes (LABs), non-aromatic hydrocarbons (NAHs), and organochlorine pesticides (HCHs, DDTs), caused damage to the Harbor’s marine ecosystem as well as pose significant health risks to seafood consumers.

LABs are supposedly derived from the use of synthetic detergents. Therefore, the benefit of monitoring LAB concentration is its use as a tracer of pollution by synthetic detergents and domestic wastes in the aquatic. NAH, also an organic compound found in petroleum products, can be used as tracers of pollution. A study (Y.S. Wong 1995) done on the NAH level in Victoria Harbor showed substantial petroleum contamination. The average concentrations of NAHs found in sediments from Victoria Harbor were much higher than those found in unpolluted embayments. Both these substances are primarily found deposited in the bottom sediments.

Organochlorine pesticides such as HCH and DDT have been a prevalent problem throughout the world. DDT, short for dichlorodiphenyltrichlorethane, was praised as an effective and inexpensive pesticide when it was first introduced in 1947.(Benarde 1989) It was originally thought to be safe enough to be sprayed on the streets where children could come in contact. The problem DDT poses is the concept of bioaccumulation and biomagnification. DDT accumulates in the fat cells of an organism. In this case, bioaccumulation occurs when DDT accumulates inside an organism and biomagnification is seen when DDT accumulates through trophic levels. When seafood consumers are exposed to bioaccumulated DDT fish, DDT is biomagnified as it is passed on to be stored in the consumer’s fat cells.

Although it has been banned, a black market for DDT remains in developing countries because of its relatively low cost to manufacture and its effectiveness as a pesticide. A study was conducted in Xiamen Harbor of China and Victoria Harbor to test for DDT concentration and other organic compounds. Concentrations of DDT in the sediments of Xiamen Harbor range from 4.45-311 ng g^-1. Hong Kong, on the other hand, contains only 1.38-30.3 ng g^-1.(H. Hong 1995) The study also shows no new DDT input to Victoria Harbor. When DDTs are transported into the sediment, they transform into DDD or DDE. Samples of marine sediments taken from Victoria Harbor indicate a significantly high proportion of DDE, 20-38%, compared to only a minor one, less than 15% DDE, from Xiamen Harbor of China.(H. Hong 1995) This figure indicates a high amount of past DDT input in Victoria Harbor but low concentrations of new DDT input. Unfortunately, the flip side of low DDE percentage is the high DDT concentration in the sediments, indicating a prevalent use of DDT in China.

The discharge of raw sewage and nutrient-rich industrial waste into the ocean results in an increase of nutrient level. This increase in nutrient level stimulates "red tide" formation. This phenomenon is related to the growth of a specific aquatic dinoflagellate on which shellfish feed. As these dinoflagellates bloom, so do the species of the algae Gymnodinium and Gonyaula, a predator of the dinoflagellate.(Benarde 1989) Oysters, clams, mussels, and scallops feed harmlessly on these protozoans. The shellfish neutralize the protozoan toxins, however, human ingestion of these shellfish leads to shellfish poisoning. This is a severe public health problem, effects of shellfish poisoning can lead to anywhere from vomiting to more severe problems of paralysis, respiratory impairment, and loss of muscular coordination of arms and legs.

Nutrient rich level also causes the abundance of diatoms. Marine diatoms have recently been used to study the relationship with hydrography, nutrients and primary productivity. Many factors could affect the abundance of diatom valves in Victoria Harbor sediments such as water currents, sedimentation rate, depth, and nutrient levels. (Banquin Hong 1996) The abundance of diatoms can be used as a bio-indicator of primary productivity, nutrient level and eutrophication of the Harbor.

Inorganic Pollutant

It is believed that film-processing factories, dyeing industries, ship leakage, paint, aerosol from vehicles (roadside dust), etc., are the sources of heavy metals in urban runoff and sewage discharged into Victoria Harbor. Unsurprisingly, sediments in Victoria Harbor are found to be highly contaminated (200-400 ppm or more) with copper, zinc, lead, nickel and other metals.(Chan K.M. 1995) Large accumulations of copper, zinc and lead were found in the tissues of mussel and barnacles collected in Victoria Harbor. Again, this is a great concern to the public health of Hong Kong, with seafood being the staple of protein source.

Heavy metals such as lead or cadmium are not beneficial to the human metabolism, unlike the essential metals zinc and copper. However, all are toxic at high concentrations. Because heavy metals accumulate in the tissues of marketable seafood, the public is essentially exposed to toxic levels of heavy metal.

A study was conducted in 1983 to examine the concentrations of copper, zinc, cadmium and lead in rabbitfish collected in Victoria Harbor. Results of the study indicated higher concentrations of lead and cadmium in the gills and vertebrae, copper levels highest in the viscera and zinc levels lowest in muscle as compared to the other parts of the body. Comparing the cadmium and lead concentrations in this study to fish collected outside of Victoria Harbor, cadmium and lead concentrations in the rabbitfish in this study were significantly higher. To put this in another perspective, lead concentrations of fish found in this study were TEN times higher than lead concentrations found in the Atlantic cod. All other metals were found to be higher in the fish from Victoria Harbor. The high lead content may have come from the use of leaded gasoline, the sample sites received sewage from urban runoff which might have contained a large amount of roadside dust heavily contaminated with lead. Unfortunately, heavy metal concentrations learned from this study did not effect the control of increasing concentrations of heavy metal. A study in 1995 recorded in heavy metal levels higher than those reported in 1992, indicating that the contamination of Victoria Harbor may be increasing. (Chan K.M. 1995)
 

Table of Yearly mean levels of trace metals (mg kg^-1 ) in the sediments of Victoria Harbor (Huang&Hong&Wong 1996)
 

Year	Copper(Cu)	Chromium(Cr)	Zinc(Zn)	Lead(Pb)
1975	65.3	35.5	160.5	68
1990	484	76.2	189.6	71.5
1991	531.4	113.1	207	81

 

Problems and Opportunities

Hong Kong’s Victoria Harbor is undoubtedly under environmental distress. Problems are the combined social, economic, political, geographical and technical constraints on the sustainability of the Harbor. In order for Victoria Harbor to reach environmental sustainability, defined by Goodland and Daly as the maintenance of natural capital, these constraints must be overcome. Achieving environmental sustainability will "ensure the maintenance of natural sinks for humanity's wastes"(Goodland and Daly 1996), providing a natural solution to the unnatural pollution.

Geographical Problems

Hong Kong is a mere 990 sq. km. And yet it supports a population size of 5,542,869, averaging nearly 5,598 people per sq. km (www.theodora.com/hong_kong_geography.html). Overpopulation has become an immediate problem in urban areas as space is becoming increasingly scarce. To combat this problem, Hong Kong has directed its efforts toward land reclamation in an attempt to prolong its carrying capacity. Although this may provide a temporary relief to the problem of overpopulation, it leads to more difficult long-term environmental problems.

Technical Problems

Victoria Harbor is threatened by both point and non-point source pollution. Point source pollution is an identifiable discharge point of a pollutant. There are an estimated 300 million tons of untreated sewage discharged into Victoria Harbor. (Connell 1998) Victoria Harbor’s non-point source pollution includes agricultural runoff, street runoff, and faulty sewer systems. To combat point source pollution, the Environmental Protection Department of Hong Kong established the Water Pollution Control Ordinance in 1994 to control the quantity and quality of discharges into the Harbor. This ordinance requires "owners of premises to make wastewater connection to public sewers and to maintain proper operation of waste treatment facilities". Non-point source agricultural runoff is controlled under the provision of the Livestock Waste Control Scheme.( http://www.info.gov.hk/info/aaep.htm)

Organic pollutants such as livestock waste from agricultural runoffs and raw sewage causes severe problems to the Harbor’s water quality. Eutrophication results as organic pollutants act as a nutrient rich food source for algae, causing murky water and uncontrollable algal blooms. Oxygen in the water depletes and eventually native fish are out competed by zone specific fish. During summers when sunlight is plentiful, photosynthetic organisms consume organic pollutants. These organisms become food for algae that eventually leads to the formation of red tides. Red tides are a problem because it affects the seafood industry, the effect of shellfish poisoning. The local seafood industry is most hard hit during these times.

Inorganic pollutants also pose a severe threat to the Harbor’s fauna. Heavy metals from urban runoff and sewage discharged into the Harbor have been found at high concentrations in local seafood. Studies have indicated a steady increase of heavy metal concentration in the Harbor over the past 20 years.(Chan, K.M 1995)

Land reclamation has become a hot topic in the environmental field because of its environmental consequences. The dredged sediment that accompanies land reclamation has been a constant source of pollution. The problem is further compounded as most of the dredged sediment is contaminated with heavy metals and organic micro-pollutants. Nearly 400 million m³ of dredged marine sediment will be generated from the new airport development, requiring disposal in the next 15 years.(Wong, Rootham, & Bradley 1992). Most of the dredged sediment will be disposed of in marine spoil dumping sites located off the main island. Heavily contaminated sediment is left in situ. We risk the remobilization of the heavy contaminated sediments into the water column if the contaminated sediment were to be moved. Current Hong Kong Environmental Protection Department (HKEPD) controls of dumping activities are governed under the Dumping at Sea Act 1974. Licenses must be issued for permission to any dumping activities.

Social Problems

Two social constraints on the sustainability of the Harbor are the undying population growth and the general public consensus on environmental issues. Hong Kong’s population has grown exponentially over the past several decades, due at large to its economic growth. At this population growth rate, Hong Kong will soon reach its carrying capacity, defined as "the maximal population size of a given species that an area can support without reducing its ability to support the same species in the future"(Goodland and Daly 1996). Unless the population growth can be slowed down, the longevity of the land will be of question in the future. The government currently assesses this problem by accommodating population growth with the expansion of land, not controlling the population growth.

It is important that the "predictability of attitudes and intentions for actual behavior on environmental problems"(Hamid & Cheng 1995) are taken into account when discussing environmental problems. Any strategy to reduce pollution must include public education if there is to be any significant long-term reversal in environmental pollution.(Hamid & Cheng 1995)

Economic Problem

The true population of Hong Kong is more than the estimated because of the perpetual influx of tourists. Tourism is a significant contributor to Hong Kong’s economy. 10 million annual visitors flood the already crowded streets of Hong Kong (Chan 1995). It is also a significant contributor to Victoria Harbor’s pollution problem, as most tourists live in hotels situated alongside Victoria Harbor. The Government formulated a Sewage Strategy to alleviate the problems of sewage discharge. "Some $12 billion (1993 prices) will be spent on new sewerage projects. These include a $8.1 billion high priority programme (HPP) to abate pollution in the central harbour. Upon its completion by 1997, the HPP will bring about major improvements to water quality in Victoria Harbour."( http://www.info.gov.hk/info/aaep.htm)

Political Problems

The power of politics is capable of radically altering the face of Victoria Harbor , for better or worse. Politics is an integral part of the economic, social, and technical constraints aforementioned. If policy were initially geared towards environmental sustainability, Victoria Harbor would not be in its current state of crisis.

Opportunities

There is not one solution to the many problems Victoria Harbor faces today but there are many opportunities for positive change to its environment. Much of the technical constraints on the sustainability of the Harbor can be attributed to problems of policy. To reduce the amount of point source pollution, the government must apply strict enforcement laws and actions. Point source pollution is happening because the government passively allows the dumping of raw sewage. A first conviction under the water pollution control regulations of WPCO in 1995 constitutes a maximum penalty of HK$200,000. Second or subsequent convictions still maintain a maximum penalty of HK$200,000.(EPD 1996) This does not provide the negative reinforcement necessary to discourage illegal dumping. More severe subsequent fines, possibly doubling fines for each subsequent conviction, should be implemented plus consideration of jail time. A three strikes law can also be implemented. When an offender commits its third offense, the institution will be shut down. Higher fines will also help alleviate the cost of more enforcement.

Policy makers can also consider increasing taxes to those that have been issued permits to dump substances into the Harbor. This will promote alternate ways of handling the discharge, alleviate costs of stronger enforcement, and encourage better technology of handling waste. "Permanent long-term improvements to water quality will require a comprehensive upgrading of the territory's sewerage infrastructure" (http://www.info.gov.hk/info/aaep.htm).

Social problems can be alleviated through the power of the media. Public education is important in order to reach the core of the problem, the citizens. People of Hong Kong are highly influenced by the television media because 1) nearly every household has a television, 2) having only two Chinese channels increases the likelihood that an environmental commercial will be seen, 3) word of mouth is effective because of the dense population. The media can therefore be extremely effective in educating the public. Policy makers should encourage TV stations to spread the ‘environmental’ word, provided that the TV stations will receive something in return.

Overpopulation may also be alleviated through public education. Studies have shown that past behavior plays a significant role in determining future behavior. A person who previously demonstrated an act of environmental friendly behavior is likely to perform other environmentally friendly acts.(Cheng 1995) Increasing the opportunity for the younger generation to be involved in proenvironmental activities will "establish past behaviors that would be difficult to ignore in adulthood."(Cheng 1995) The population of 65 years and over, generally considered the generation unexposed to pro-environmental education, makes up 10% of the current population. (http://www.odci.gov/cia/publications/factbook/hk.html) The U.S. Census Bureau estimates the largest age structure by the year 2050 will be 65 years and over (see Fig.4). Ideally, a non-proenvironmental generation of 65+ in 1997 will be supplanted by a large proenvironmental generation of 65+ in 2050. The ECC must plant this environmentally friendly seed through campaigns and interactive surveys with the young public. Ultimately, policy holds the key to both short term and long term change to Victoria Harbor.

A perfect revamp of Victoria Harbor to its natural order is unrealistic. However, positive changes can be made. It will require efforts ranging from the Governor of Hong Kong to the average Joe Ho on the street; political to individual.

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