1. Overview

With a geographical coordinates of 20^o53’ to 21^o23’ North and 105^o44’to 106^o02’ East, Hanoi is located in the heart of the Red River Valley, one of the largest deltas in Vietnam. Hanoi is adjacent to Thai Nguyen in the north, Bac Giang, Bac Ninh and Hung Yen in the east, Hoa Binh, Phu Tho in the west; Ha Nam and Hoa Binh in the south. According to 2008 statistics, Hanoi has a natural area of 3324.90 square kilometers, divided into 29 district-level administrative units, including 10 urban districts, 18 rural districts, 1 town and 580 commune-level units (404 communes, 154 wards and 22 townships). The population as of 2008 was 6,232,940 people.

It was not until late 19^th century did Hanoi begin to embark on its urban development. In 1888, Hanoi had an area of only 200 hectares and a population of 50,000. 120 years later, in 2008, the population of the nine urban districts alone was already 2,217,300 people and the natural land area was 179.45 sq km (see Hanoi Statistics Report, 2008). The substantial bodies of water, ponds and lakes, are an invaluable asset to Hanoi, and the most recent survey in 2010 shows that there are an estimated 110 natural and artificial lakes left, covering a total area of 1,165 hectares.

Before it was established in 1010 as the capital of Vietnam under the Ly dynasty, Hanoi was only an ancient village situated along the bank of the To Lich river, flanked on its back solidly by Mount Nung. As the name suggests, Hanoi (literally ‘in the loop of a river’) is a city of rivers and lakes. In the old days, Hanoi was built on simply a raised area of land surrounded by the Red River to the east, the To Lich and Kim Nguu rivers to the west and south, and by paddy fields and marshes.

The current city is substantially expanded, with To Lich and Kim Nguu becoming major parts of the drainage system of the city. Many ponds and lakes have been filled up and leveled under the pressure from urban development, but such rivers as the Nhue still function as a crucial drainage system that help protect the city against flooding and inundation.

During the development of Hanoi into a national cultural, economic and political centre, many wetlands have been leveled off and turned into urban areas. There are only 20 lakes left in the centre of the city, covering a total area of 756 hectares. Urban development has also led to substantial diminution in both the quantity and quality of the natural ecological system in the wetlands of the city.

Wetlands in general and rivers and lakes in particular play a tremendous role in the spiritual and material life of Hanoi people. They enhance the environmental, cultural, historical, spiritual and landscape values of the capital. For many reasons, however, their survivals are being critically threatened.

With the recent inscription of the Imperial Citadel of Thang Long-Hanoi on UNESCO List of World Heritage, it is hoped that the people of Hanoi will join hands to preserve the invaluable legacy and to be a really a green, beautiful, heroic and peaceful city.

2. Wetlands in Hanoi

2.1. Hydraulic and climatic conditions

The climate of Hanoi is typical for a monsoon tropical area with two main seasons: the hot season and the cold season. The hot season, which lasts form April to October, is characterized by intense heat and heavy rain. The prevailing wind is the southeasterly wind, accompanied by thunderstorms and typhoons. The hottest months of the year are June and July which is also the rainiest. January has the lowest average temperature and precipitation when the prevailing wind is the northeasterly wind. April and October are transitional seasons that give Hanoi a four-season climate pattern with four distinct seasons: spring, summer, autumn and winter.

The annual average temperature of Hanoi is fairly high: 24⁰C.

Humidity of Hanoi is lowest in winter (70% in December) and highest in spring (March) when there are many spells of drizzles. Average humidity in the air fluctuates between 70% and 80%.

Precipitation averages 1,870 mm. There are on average 140 rainy days, distributed unevenly in 12 months. The rainy season brings 1400-1500 mm of rainwater, accounting for as much as 85% of the total amount of the whole year. The rainiest season is July with about 16 to 18 days of rain and 300-350 mm of rainfall. Sometimes rains come down ceaselessly for days, causing flooding and inundation that affect considerably the function of the city.

Hanoi is also directly exposed to an average of five to seven typhoons. These typhoons are often coupled with the rising water level of the Red River, threatening to destroy the dykes and levees and causing adverse impacts to the life and work of the people living in the riparian areas. Many activities and services in the city are disrupted or discontinued as a result of these typhoons, especially when climate change is more evident than ever.

Hanoi also has numerous spells of sunshine every year, concentrating mainly in summer and autumn (May to November). The total duration of sunshine averages 1436 hours, which affect enormously the hydraulic conditions of the wetlands in the city.

Hanoi is crisscrossed with rivers and streams with approximately 0.5 kilometer of river per one square kilometer. These rivers and streams are tributaries to two major systems: the Red River and the Thai Binh River. The slope of the riverbed is insignificant and rivers flow around the city in meandering courses.

The hydraulic conditions of Hanoi, which correspond to its topographical and climatic features, fall into two main categories: the flooding season and the dry season. The flooding season coincides with the rainy season, which last from July to October. Flooding reaches its peak in August, bringing with it 70% to 75% of the total amount of rainfall of the year. The dry season usually lasts seven months, from October to May. The levels of rainfall and river water are lowest during March.

Subterranean water: Hanoi has a large and stable reservoir of underground water with fairly good quality and a buffer layer that protects it from pollution. The total volume of underground water storage averages 1.0 to 1.2 million cubic meters a day. This water, however, has a high concentration of manganese (Mn) and iron (Fe) and is therefore is unsuitable for drinking and daily use.

2.2. Major categories of wetlands in Hanoi

Based on the RAMSAR Convention on Wetlands (IUCN, 1997), wetlands in Hanoi fall into nine major categories:

Inland wetlands

1. M) Permanent rivers/creeks/streams

2. O) Permanent Lakes (over 8 hectares)

3. Tp) Pools (under 8 hectares)

Human-made wetlands

4. 1) aquaculture pond (shrimps, fish,

5. 2) Ponds (farm and stock ponds, small stock tanks, or area less than 8 ha)

6. 3) Reservoirs

7. 4) Seasonal flooded agricultural land

8. 5) Wastewater treatment lakes

9. 6) Drainage canals

2.3. Major wetland systems in Hanoi

Hanoi is dubbed “a city of ponds and lakes”, which is not accidental. Through the vicissitudes, the number of ponds and lakes in Hanoi varies according to different periods of history. Rapid urbanization necessitates greater land area for dwelling and infrastructure. Hanoi still retains a fairly large number of ponds and lakes. More than a decade ago, there were 40 lakes with a total area of more than 850 hectares in the central part of the city. Currently only 24 of them survive, covering approximately 756 hectares.

2.3.1. Some major lakes in Hanoi

Due to the mismanagement and absence of a proper planning, Hanoi has lost many of its natural lakes and marshes. The city centre is where some of the largest lakes are located, such as West Lake, Bay Mau, Truc Bach, Hoan Kiem, Thien Quang, Thu Le, Giang Vo, Ngoc Khanh, Linh Dam lakes and Van Tri Marsh. Other lakes of various sizes can be found in the other districts and prefectures of the city. The most important lakes of the city are tabulated as bellows:

Table 1: Lakes in the city centre in different periods of time

(Source: Office of Traffic and Civil Engineering of Hanoi, 2001 – cited by Hoang Van Thang et al, 2002)

2.3.2. Major rivers in Hanoi

The former city centre had four rivers (excluding the Red River) that served as the major drainage system, extending over 40 km. These included: the To Lich River (13.5 km), Lu River (5.8 km), Kim Nguu River (12.2 km) and Set River (6.7 km) (see Table 2). These rivers originated from the city centre and received the waste water from smaller canals and sewers before flowing southwards and emptying into the Nhue River at Buou Bridge. Together these four rivers constituted the main drainage system for the centre of Hanoi and provided a substantial source of water for agriculture and aquaculture. Of these four rivers, the To Lich had the largest area of 77.5 sq km, divided into eight subsections for ease of management.

The sectional area of these rivers was fairly large, except for the few places that intersected traffic roads. Currently all the untreated waste water from the factories, hospitals, public conveniences, and households was emptied into these rivers. The draining capacity of these rivers is also seriously affected due to the encroachment of houses on the banks of the rivers which causes severe pollution to the quality of the water in the city.

Table 2. Rivers in Hanoi and the volume of waste water dumped into them

(Source: Hanoi Department of Natural Resources and Environment, 2001 – cited in Hoàng Văn Thắng et al., 2002)

2.3.3. The drainage system of Hanoi

A network of 56 canals with a total length of 36 km connected to the rivers plays an important role in holding rain water and waste water that empty into these canals from every area of the city centre. The total length of canals that are more than five metres wide is 143 km. The environmental conditions in these canals are degrading seriously and the courses of the canals are becoming smaller due to the piling up of mud, sediment and wastes that are not regularly dredged.

The drainage system of Hanoi is mainly the system of sewers that collect untreated waste water from different places and empty into To Lich River. The total length of this drainage system is around 300 km, of which 74 km was built under the French colonial period and divided into five sections in Lo Duc, Ba Trieu, Tran Binh Trong, Phan Dinh Phung, Trinh Hoai Duc, Nguyen Truong To, and Pham Hong Thai. The rest of the system was built after 1954 in the expanded areas of the city centre. The whole system together is inadequate and still fails to meet the rapid urbanization of the city. The final dumping points are in Thanh Liet Dam and the pumping station of Yen So.

2.4. The importance of wetlands in Hanoi

2.4.1. The main functions of wetlands in Hanoi

The lakes and rivers in Hanoi play an important role in the urban environment of the capital city. These values and functions are summarized in Table 3 below:

3. The values and functions of lakes in Hanoi

Notes: x: low; xx: average; xxx: high

Of all the functions above, the ability to moderate rainfall and control flood is of extreme importance to Hanoi as an urban space.

Currently untreated waste water from households and factories is emptying uncontrollably into different lakes in Hanoi. In recent years, therefore, these lakes have become seriously polluted by urban waste water. Alarmed by this critical situation the authorities have decided to protect some of these lakes, particularly Hoan Kiem, from such potentially harmful effects.

Most lakes in Hanoi have been associated with a surrounding park or garden of the city. A park with a lake inside is an ideal peaceful place for the people of the city to meet and entertain themselves.

For most of the lakes in the city centre, the fish-raising function is no longer a primary function. Fish, if any, serve mainly to make the environment of the lake better, rather than adding significantly to the annual fish catch.

2.4.2. Biodiversity in the wetlands of Hanoi

The rivers and lakes in Hanoi provide habitat for many kinds of animals and plants. They are also home to many species of waterfowl (see Table 2.4)

Table 4. Biodiversity of the wetlands in Hanoi

Source: Hoàng Văn Thắng et al., 2002

3. Management and conservation of wetlands in Hanoi

3.1. Some common views on the management of wetlands

Management of wetlands can be done in different ways, depending on the purposes of the managers. Sometimes these purposes are conflicting, such as the prevention of dumping pollutants into wetlands and the use of wetlands as waste-water treatment areas. Also, the management of wetlands is governed by the wetlands-related regimes and policies.

Objective-based wetland management refers to the selection of management objectives based on the functions of wetlands. Management objectives may include, but is not limited to, the following:

1. Maintaining the quality of water;

2. Regulating and controlling floods;

3. Providing natural systems for the treatment of pollution in the air and water.

4. Maintaining the source of genes and providing samples about the natural biomes;

5. Creating a clean and fresh air for the people;

6. Providing habitat, breeding grounds and a source of food for waterborne species, especially rare species (Hoan Kiem Turtle (Rafetus leloii), black coot, etc.)

7. Providing human beings with foods and other biological products

8. Serving scientific and training purposes;

9. Serving as entertainment space.

3.2. Serious pollution in the lakes

Lakes and rivers in Hanoi are suffering from the severe environmental destruction by the human beings. This alarming fact is reflected in the following statistics: more than 4000 cubic metres of industrial and household waste water from tens of factories, businesses, and hospitals (Thuy Khu Footwear Company, Truc Bach Paper Company, Tuberculosis Hospital, etc.) is discharged into the West Lake on a daily basis. That is not to mention thousands of tons of garbage from lakeside restaurants, hotels and food-stalls directly disposed into the lake. On average, tens of thousands of fish that die from polluted water must be collected everyday.

According to a report by Hanoi Department of Science, Technology and Environment, the content of ammonia in the West Lake has now reached 1.5mg/litre, three times higher than the standard level. In smaller lakes like Thanh Nhan, Ngoc Khanh, ammonia concentration is even much higher than that in the West Lake or Hoan Kiem Lake. This is evidence for the critical condition of water pollution.

Rivers and canals are facing the same threat as the lakes, having to receive a huge amount of waste water and garbage discharged from the households living nearby. The ammoniac content in the river is estimated at 19.6-26.5 mg per litre, which is 10 times higher than the permitted level, 15 to 20 times higher than that in the water of West Lake and 20-25 times higher than in the Hoan Kiem Lake.

3.3. Encroachment of lakes

Given the exceedingly high value of land in Hanoi today, encroachment of lakes and rivers have become complicated and rapid more than ever. Within the last 10 years alone, more than 21 have already disappeared and over 150 hectares of water surface area has “evaporated”. Most of this loss can be attributed to the greedy encroachment upon lakes under development pressures.

Only such lakes as Hoan Kiem, Thien Quang and Thu Le, which are surrounded by concrete roads, are lucky enough not to fall victim to encroachment and development. Others “not-so-lucky” lakes include West Lake, which has lost 50 hectares since 1987 and Truc Bach Lake which has lost a quarter of its area. The four rivers that help drain water for the city (the Lu, the Set, the To Lich and the Kim Nguu) with a total length of 38.6 km, together with over 40 km of canals still fail to meet the standards of non-pollution and in fact the pollution level in these rivers and canals exceed manifold the permitted levels.

3.4. Inappropriate ‘rescue’ methods

The city authorities have conducted many projects to improve the environment and protect the remaining area of lakes and rivers. With the exception of the controversial case of the West Lake, most of the other projects have been rather effective, such as the embankment project for the four major drainage rivers, namely the Lu, Set, To Lich and Kim Nguu, and for Truc Bach Lake.

In a recent development, the Traffic and Civil Engineering Department of Hanoi has initiated a project to extend the improvement project to other lakes in the city, such as Thien Quang, Giang Vo, Thanh Nhan 1 and Thanh Nhan 2, with a total expense of 23 billion VND. However, these projects will be come to nothing or even become counterproductive “if the human conscience is not awakened”.

65% of the rivers and lakes are filled up and leveled; the remaining become less absorptive due to the overuse of concrete, which reduces their draining capacity. Overuse of concrete in and around the lakes also lead to the disappearance of the waterborne creatures which function as a filtering system and constitute the landscape for the lakes and the loss of genetic sources in the ponds and lakes Hanoi.

This is an observation made by scientists when they witness the constant inundation of Hanoi after just an average rain. Scientists have also proposed four sets of solutions to protect Hanoi from constant inundation and flooding.

“In the 10-year period of 1986-1996 alone, the four urban districts of Hanoi lost more than half of their water surface area. Even before the economic development projects began to affect the lakes and rivers, scientists had warned of the potential danger. But their warnings went unheeded and the authorities went ahead with their decision to license these projects, with a total disregard for the scientific warning. The consequences are clear: the people of Hanoi today are frequently affected by inundation and flooding”

Apart from civil construction projects, the embankment of the rivers and lakes has also been given critical comments from the scientific circle. “Many a time the scientists have warned the authorities against too much scree in the embankment of the rivers and lakes because this may decrease the holding capacity of the lakes. After embankment, the rivers and lakes look like an upside-down triangle, which reduces considerably their capacity and absorbability. When it rains, Hanoi then becomes a city of stagnant ponds. Water cannot be drained and the city becomes waterlogged and inundated” (Pham Ngoc Dang)

Prof. Tran Hieu Nhue from the Hydraulic Technology and Environment remarked that “The overuse and abuse of concrete in the embankment of rivers and lakes happen to reduce the ability to drain or absorb water”

He quoted, as his evidence, a series of small-sized bridges in Hoa Muc, Trung Hoa, etc. Even when the rain is not too heavy, the water become clogged and inundated because the rain cannot be emptied or drained.

3.5. The management system and its shortcomings

Together with the drainage system of the To Lich, Lu, Set and Kim Nguu, the ponds and lakes in the city have played an important role in regulating and controlling the rainfall and climate for the area. As different sectors in the city are using the lakes for different purposes, there has been an absence of integrated management that leads to overexploitation of the lakes and the aggravated conditions of inundation, environmental pollution, and land and water encroachment. Many lakes that are believed to function as a conditioner for the city have disappeared. Other lakes that bear historical and cultural values, have been changed but without any thorough research or synchronized implementation. In fact there remain a lot of overlappings, shortcomings and inadequacies in the current management of the ponds and lakes.

In many cases, one single lake is put under different ownerships and management levels, involving as many as four parties, such as the famous Hoan Kiem Lake. Lack of integrated management means that it is sometimes difficult to dredge the lakes for sanitary purposes. Noteworthy examples include the lakes under the management of not only the collectives but also the people’s committee of ward levels, such as the Van Chuong Lake, Linh Quang Lake, Bay Mau Lake and Dinh Cong Marsh and Linh Dam Swamp, etc. Due to lax management, the area of these lakes has been increasingly reduced for construction purposes; the surfaces of the lakes are covered with duckweed, vegetable and garbage, causing serious pollution to the surrounding environment.

According to a surveyed called “The Current Conditions of the Lakes in Hanoi” conducted in June 2001 by Hanoi Drainage Company, many lakes in Hanoi are under the management of different stakeholders, as summarized in the table below:

.Current management and exploitation of the lakes in Hanoi

(Source: Hanoi Department of Traffic and Civil Engineering December 2001- cited in Hoàng Văn Thắng et al., 2002)

Shortcomings in the management of lakes:

The complicated nature of lake management has led to a lack of uniformity in the exploitation and management of the lakes. Therefore, the functions of the lakes as conditioners for the regional climate have not been fully utilized.

There are discrepancies in the results from surveys and research on the wetland in Hanoi, especially data and results on the area of the lakes and the length of rivers and canals, which causes difficulties for management and conservation.

In addition, due to pressures from development and population increase, and low awareness of the people and lax management of the authorities, encroachment and pollution of the lakes are becoming more and more serious, causing added difficulties to the already overlapping and complicated management system.

Other problems include:

- Absence of an integrated and uniform planning for the sustainable use of the lakes in Hanoi.

- Compulsory observation of regulations and statutory documents on the preservation of the environment has not been strictly and regularly implemented.

- Each management unit has different interests in the exploitation and management of the lakes;

- Lack of concerted cooperation between the drainage companies and the owners of the lake;

- Serious pollution of the lake water due to an absence of garbage collecting and wastewater treatment in most of the lakes.

Some of the following pressing issues have been identified by research and evaluation of different lakes in Hanoi:

- Most of the lakes under examination are being polluted with untreated wastewater;

- Many lakes are being encroached upon due to lax management of the banks and the loops of the lakes;

- Some lakes are being rebuilt with a very slow progress;

- Heterogeneous management persists, causing difficulties to draining capacity. The level of pollution has not been sufficiently gauged, because currently in Hanoi there are is system in place to survey the quality of the lake water.

3.6. Appropriate measures and solutions

Professor Nhue is quoted as saying: “The dismantling of the embankment to widen the course of the rivers and lakes is not feasible and very costly”

He suggested different solutions to save Hanoi from constant inundation and floods by applying four feasible and inexpensive solutions. These are: building more pumping stations; maximizing the capacity of the functional Yen So pumping stations; encouraging households and businesses to build reservoirs to hold rainwater for use in the dry season and in daily life; enhancing management policies to protect rivers and lakes against encroachment”

Another solution that scientists are very much in favor of is the construction of artificial lakes for Hanoi. Architect Tran Thanh Van suggests that “there can be a system of water parks in My Dinh”. She believes that if there is a system of artificial lakes and ponds with an area of one thousand hectares, it can hold as much as 15 million cubic metres of water on rainy days and bring fresh and cool air for the city on sunny days. That is a recommended solution from the scientists, but whether it can be translated into practice depends greatly on the idea of the authorities. If Hanoi is not quick to redress its mistakes, the life of the city people will be even harder, and Hanoi will have a big problem trying to live up to its position as the capital city of the whole country.

Inland lakes in general and those in Hanoi in particular all have the following functions and roles that the authorities cannot afford to ignore. These functions must be enhanced by better management as they play a very important role in responding to climate change and guaranteeing sustainable development for the city.

All the following functions and roles must be maintained if the lakes in Hanoi are to be managed and conserved properly

· Maintaining as much as possible the natural elements of the wetlands, even when they are restored. Embankment is not an effective solution against encroachment, as embankment will lessen the absorbability of the lakes and make them stagnant. Paving bricks and stone around the lakes is also impractical and ineffective. Instead, there should be patches of grass (about 50 metres wide) to filter the wastewater before it empties into the lakes.

· The wetlands that have been converted to a different use must be restored to the greatest extent possible. If they are impossible to be restored, then artificial wetlands must be created (ponds, canals, brooks, etc). In the US, there is the “No net loss” rule in the management of the wetlands, that is to create an equally large wetland when one is converted to different use.

· The owners of the wetlands must be able to gain direct profits from their ownership, because the wider public benefit greatly from the wetlands. There must be a mechanism to pay environmental fees to the communities or individual organizations who own the wetlands to prevent them from turning the wetlands into different use for more immediate and higher profits.

· As the system of wetlands in Hanoi is both crucial and substantial, there should be a specialized unit fully in charge of the conservation and management of the wetlands. This unit should be affiliated to the city Department of Natural Resources and Environment. The specialized staff in this unit should take responsibility for the monitoring of wetlands to come up with appropriate solutions in what is known as “adaptive management”. Results from these monitoring and survey missions will help the municipal authorities to enact timely and effective conservation and management policies

· Scientific organizations in Hanoi should work together to make concerted efforts in management and conservation of wetlands based on shared experience and knowledge.

· Develop a database for wetlands in Hanoi with special attention to data from previous research or surveys to make a comparative analysis of the current wetlands and the traditional ones before conducting conservation missions.

· Pay attention to the cultural and spiritual values of the wetlands in Hanoi, which is a guarantee for sustainable and community-based conservation of wetlands.

· Reserve a special section in the Hanoi Natural Museum to introduce wetlands of the city to the visitors, including schoolchildren to raise their awareness of the importance of conserving wetlands.

· Wetlands must be integrated into the overall planning of the whole city. Only by doing this can we conserve the city’s wetlands for long-term use

· The restoration and conservation of wetlands should be seen as one of the responses to climate change to the city. As Hanoi is mainly affected by typhoons, flooding and increasing heat over an extended period of time, this may cause a sudden and severe lack of water for daily use. If the wetlands are restored and conserved, they will help reduce the effects of climate change as witnessed in the weather events in the first half of 2010. The budget for climate change response will then be cost-effective.

· Different resources in the society should be mobilized for the restoration and conservation of wetlands with full participation of all the stakeholders.

· There should be one vice chairperson of the city to be in charge of the conservation and management of wetlands, especially in the initial phase, to prevent pollution and encroachment.

· It is necessary to educate and raise the public awareness of the role of wetlands in their daily life and encourage members of the public to participate voluntarily in the conservation of wetlands (community-based conservation). Different mass organization should be involved.

· Encourage students and young staffs to carry out scientific research on wetlands in Hanoi and conservation methods.

· Integrate the education of the role, functions and services of wetlands into the teaching curricula of the schools in the city. Hold competitions on effective management of wetlands with contestants being the schoolchildren, students and youngsters of the city to raise their awareness of the importance of wetlands

· Develop a mechanism for conserving wetlands in Hanoi. A lack of regulations will result in effective management and failure to prevent violations. The role of environment police officers should be clearly defined.

· The collection and treatment of industrial waste water is highly needed before it empties into the rivers, canals and lakes of the city. Without this measure, Hanoi will never have a real and long-term solution, even when the city is ready to spend a 600 billion VND to save To Lich river. That money should go into the construction of water treatment centres in an industrial manner, which is a long-term and fundamental solution.

4. Conclusion and recommendations

Most people still have little awareness of the effects of the loss of wetlands on Hanoi. Due to the absence of an overall planning, of policies, laws and regulations on urban development and environmental protection in a market economy, Hanoi is confronting pressing environmental issues, the most notable of which is the rapid degradation and deterioration in the functions and significance of the lake system. Some lakes are polluted almost beyond recognition and the biodiversity of the lakes is also being affected for different reasons.

For the lakes in the city centre to be well-protected and managed, there should be intersectoral, comprehensive and interdisciplinary solutions. Significant investment should be made in the field of supplies, technology, expenses, organization, human resource development and formulation of legal environment while continuing to call for joint action by the community to conserve and manage these lakes.

The management and conservation of wetlands in Hanoi serve to maintain the functions and properties of this wetland ecological system. Therefore, there must be effective cooperation among relevant management agencies and scientific organizations, together with the participation of the local community.

Sustainable management of the wetlands in Hanoi and conservation of values, functions and properties, especially maintaining biodiversity and the ability to drain water to reduce flooding and inundation, conditioning the air and providing a space of entertainment, enhancing historical, cultural and aquaculture values.

In the meantime, the establishment of an effective management mechanism is urgent for the wetlands of Hanoi. Specific policies and statutes issued by the city authorities are of crucial importance. The timely prevention of encroachment and disposal of waste into rivers and lakes in Hanoi is badly needed.

The planning and use of city land resources must be carefully calculated to take into account the functions and properties of the ponds, rivers and lakes in Hanoi. Wetlands must not be filled up to give way to the construction of roads and houses.

The inventorying and evaluation of the economic values of the wetlands in Hanoi must be done meticulously.

There must be a special agency of the city directly responsible for the overall management of the local wetlands.

The management board and the professionals as well as the general public should be well-qualified and perform their jobs professionally and ethically appropriate in the management and conservation of wetlands.

Raising the awareness of the values, functions and properties of the wetlands for the managing staff and the local community should be a priority

The public and social mass organizations such as the Women Association, the Youth Union, the Elderly Association, teaches and students of the universities should be encouraged to take part in the management and conservation of wetlands in Hanoi

It is important to seek support from the Central Government and international agencies in management and conservation efforts.

It is also necessary to formulate and enact “Conservation and Management Action Plan for the Wetlands of Hanoi” with a long-term goal of improving the capacity of sustainable management of the wetland ecosystem in order to preserve the ecological, social and environmental functions for an improved quality of life and sustainable development for the general public.

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