INTRODUCTION
Water is a vital resource essential for life and production, yet it faces significant challenges due to economic development, population growth, environmental pollution, and climate change As populations expand and economies grow, the demand for water intensifies, leading to its overexploitation Urbanization, agricultural practices, and industrial activities further strain both the quantity and quality of this precious resource, highlighting the urgent need for sustainable water management worldwide.
Vietnam faces significant challenges, particularly concerning environmental pollution caused by human activities in both production and daily life Addressing these critical issues is essential for the country's ecological health and sustainability.
In major cities like Hanoi and Ho Chi Minh City, pollution has become a critical issue, encompassing wastewater, solid waste, medical waste, air pollution, and noise pollution The rapid urban population growth in recent years has overwhelmed the drainage systems, leading to a significant decline in environmental quality Most wastewater and waste, both inorganic and organic, are discharged directly into the environment without adequate treatment Authorities report that residents in these large cities generate thousands of tons of trash daily, with households contributing hundreds of thousands of cubic meters of toxic waste.
West Lake, located in the Tay Ho district of Hanoi, is the largest natural lake in the city, spanning over 526 hectares with an 18 km perimeter This freshwater lake, a remnant of the old Red River, serves as a vital ecological resource, often referred to as the "lungs of the city." It plays a crucial role in local flood control and water storage during the dry season, while also contributing to sewage treatment through its natural cleaning mechanisms However, recent contamination from overflowing rainwater and domestic wastewater has posed significant environmental challenges, impacting both the ecosystem and the quality of life for residents The area surrounding West Lake is planned to become a central urban hub in the near future, highlighting its importance to Hanoi's development.
I have chosen to undertake a student thesis titled “Assessing the Water Quality of West Lake in Hanoi.” This project aims to enhance environmental protection and improve the water quality of West Lake.
Figure 1.1 Map of the study area (Source: Google map)
GOALS AND OBJECTIVES
Goals
This thesis conducts a thorough investigation into the water quality of West Lake in Tay Ho district, Hanoi, by collecting and analyzing relevant data and statistics The primary objective is to identify effective solutions for enhancing water quality and safeguarding the ecosystem of West Lake.
The thesis was carried out to achieve the objectives as follows:
- Collecting data on natural conditions, population and socio - economic conditions of area surrounding West Lake;
- Sampling, analyzing, and assessing the current status of water quality in the study area around West Lake;
- Initially identifying major impacts of water contamination in the study area around West Lake;
- Proposing solutions to improve the water quality and protect the ecosystem of West Lake.
METHODS
Investigating the study area
Due to the lake's significant size, with a diameter of 18 km and an area of 5.3 km², the study will focus on a specific section near the edge for convenient water sampling Additionally, surrounding areas will be examined to provide a comprehensive assessment of the lake's overall condition.
The thesis will select three investigation areas, each located approximately 1 km apart Following the selection of these study areas, a preliminary investigation will be conducted to gather essential information.
+ Different types of activities in the study area:
+ Primarily assess the water quality of the lake by some visual indicators;
- Waste water from boathouse which are made to be restaurants, bars in the lake;
- Waste water from households live around the lake;
- Trash from people who throw to the lake.
Interviewing
In this study, I will conduct interviews with 20 randomly selected residents living near the edge of West Lake to gather insights into their perceptions of the lake's water quality The findings from these interviews will be presented in Table 3.1, highlighting the local community's understanding of water quality issues in the area.
Table 3.1 Results of interviewing people live around West Lake area
Their knowledge on the status of water quality of West Lake
Activities affecting the lake’s water quality
Major impacts of water contamination that they can feel
Their proposed solutions to improve and protect the lake’s water quality
Assessing the water quality of West Lake
Based on the purpose of research and analysis conditions, the thesis chooses the following indicators to analyze and assess:
- Physical criteria: pH, turbidity, temperature, content of suspended solids (TSS) and content of dissolved solids (TDS)
- Chemical criteria: BOD 5 (Biological Oxygen Demand), and COD (Chemical Oxygen
3.3.2 Selecting locations and sites of sampling
Due to the extensive area of West Lake and the limited scope of this thesis, the study focuses on the section from Thuy Khue Street to Phu Tay Ho Spanning a total length of 18 km, three water sampling locations have been designated, each approximately 1 km apart Samples will be collected at 9:00 AM to align with peak water usage among residents.
The data of water samples will be filled in the following table:
Table 3.2 Water samplings of West Lake
The middle of the lake
Take water from lake by plastic bottle
Distance about 1km from the edge
Take water from lake by plastic bottle
The edge of the lake
Take water from lake by plastic bottle
3.3.3 Tools and methods for sampling
Tools and methods used for sampling follows the standards:
TCVN 6663-1:2011 (ISO 5667-1: 2006) – Water quality- Sampling Part 1: sampling guides and techniques
TCVN 6663-3:2008 (ISO 5667-3:2003) – Water quality- Sampling Guidelines of sample preserving and processing
TCVN 6663-6:2008 (ISO 5667-6:2005) – Water quality - Sampling Sampling guidelines on rivers and streams a Sample container
When selecting sample containers, it is essential to choose options that prevent loss from evaporation, absorption, and contamination Ideal containers should be durable, solid, and easy to seal and open They must also withstand heat and weight while being reasonably shaped and sized for convenience Additionally, these containers should be easy to clean, reusable, readily available, and cost-effective.
For optimal sampling, I chose a 500ml white plastic bottle as the sample container It is essential to clean the bottle thoroughly and rinse it three times with water at the sampling location before use.
To ensure accurate sampling, all bottles and containers must be thoroughly cleaned, utilizing detergent and acidic solutions before rinsing with distilled water Samples should be collected in 1.5-liter plastic bottles, and it's essential to prepare necessary materials such as tapes, markers, and sealed barrel sponges for proper sampling Additionally, careful preservation and transportation of the samples are crucial for maintaining their integrity.
All bottled water samples must be cooled to approximately 4°C and transported to the laboratory The target pH and temperature should be measured on-site Samples should be kept cold and stored in a dark place, as they typically remain viable for up to 24 hours.
This study collected three water samples simultaneously at 9:30 AM on a sunny day, when residential water demand is at its peak.
To collect water samples effectively, begin by selecting and thoroughly cleaning three bottles Next, rinse the bottles in the waters of West Lake, submerging them at a depth of 0 to 20 cm while ensuring that no debris enters the bottles.
+ Step 3: Covering the bottle and writing background of the water sample clearly (time, collector…)
+ Step 4: Preserving the water samples following the standard
3.3.4 Analysis Methods a pH measurement method pH was measured by litmus paper and then compared the color of litmus paper with color table to determine the pH of the water b Temperature measurement method
Use a thermometer directly at the sampling location and record the results c Turbidity measurement method
The turbidity of the water samples was measured by fast measuring device as Micro TPI d NH 4 + measurement method
The N + measurement method of the water samples was measured by TCVN 5987-1995 e PO 4 3- measurement method
The PO4 3- measurement method of the water samples was measured by TCVN 2322 f COD measurement method
The COD measurement method of the water samples was measured by strong oxidation factors like K2Cr2O7 g Method of analysis of Total Dissolve Solid (TDS)
The total dissolve solid of water was measured by fast measuring device as TDS Meter h Method of analysis of suspended solids
Suspended solids SS is calculated by the formula:
To determine the weight of the filter paper, m1 is recorded after drying it at 105°C for approximately 45 minutes until a constant weight is achieved, prior to the filtration process Similarly, m2 is measured after drying the filter paper under the same conditions for 45 minutes, but this time following the filtration process.
V: Sample volume filtered (L) i Methods for determination of BOD 5
The analyzed samples exhibited significantly high levels of BOD5, necessitating dilution to an appropriate factor prior to analysis To ensure accurate results, the water used for dilution was bubbled to saturation and supplemented with essential nutrients.
After diluting the sample, we measured the initial Dissolved Oxygen (DO0) at 20°C The sample was then incubated in a BOD-specific incubator at 20°C for five days Following the incubation period, we re-measured the Dissolved Oxygen (DO5) and calculated the BOD5 value in mg/L by subtracting the BOD5 values of the blank sample.
BOD 5 : BOD values after 5 days (mg/L)
DO0: DO values at 200C after diluting (mg/L)
DO 5 : DO values at 200C after 5 days incubating at 200C (mg/L)
F: dilution factor j Method for determination of COD ( Ferroin Indicator reagent)
- b is the volume of FAS (Ferrous Ammonium Sulfate) used in the blank sample,
- s is the volume of FAS in the original sample,
- n is the normality of FAS k Methods for determination of coliform
The analysis results will be filled below:
Table 3.3 Analyzing results of some water indicators of West Lake
The thesis uses the following standards of Vietnam to assess the water quality at the research area:
- QCVN 38:2011/BTNMT: National technical regulation on Surface Water Quality for protection of aquatic lifes
- QCVN 39:2011/BTNMT: National technical regulation on Water Quality for irrigated agriculture
- QCVN 40: 2011/BTNMT: National Technical Regulation on Industrial Wastewater
- QCVN 02: 2009/BYT: National technical regulation on domestic water quality
Table 3.4 Limits of water quality indicators
QCVN 38:2011/BTNMT: National technical regulation on Surface Water Quality for protection of aquatic lifes
3 Total Suspended Solids (TSS) mg/L 100
4 Total Dissolve Solids (TDS) mg/L 1000
QCVN 39:2011/BTNMT: National technical regulation on Water Quality for irrigated agriculture
3 Total Dissolve Solids (TDS) mg/L 2000
QCVN 40: 2011/BTNMT: National Technical Regulation on Industrial Wastewater
- Column A is the limit values regulation of pollution indicators in discharging of industrial wastewater into water sources used for domestic water supply purposes
- Column B is limit values regulation of pollution indicators in discharging of industrial wastewater into water sources not used for domestic water supply purposes
QCVN 02: 2009/BYT: National technical regulation on domestic water quality
RESULTS AND DISCUSSION
Socio - economic conditions of Tay Ho district
Socio - economic conditions of Tay Ho district
Since its establishment, Tay Ho District has focused on developing an economic structure based on the "Services – Industry - Agriculture" model The industrial production value has experienced an impressive average growth of 31.2% per year, while the value of travel services and trade has increased by an average of 14.9% annually Conversely, the agricultural and fisheries production value has seen a decline of approximately 3.8% per year (Portal gate of Tay Ho district).
In 2008, the industrial production value in the non-state sector reached 177.2 billion VND, while commercial sales in services and tourism totaled 4,992.4 billion VND, and agricultural production was estimated at 15.45 billion VND In the first half of 2009, the non-state industrial production value was 79.13 billion VND, achieving 45.3% of the planned target; commercial revenue from services reached 2,847.02 billion VND, or 47.3% of the plan, and agricultural production value hit 6 billion VND, reaching 42.9% of the goal Additionally, state budget revenues in the district showed a positive growth trend, with revenues of 368.75 billion VND in 2008 and 148.19 billion VND in the first six months of 2009 (Tay Ho district portal).
In the first half of 2009, Tay Ho district successfully created jobs for 2,608 workers and reduced poverty for 21 households, achieving 35% of its poverty reduction goal The material and spiritual well-being of the community has significantly improved, with active promotion of information and cultural activities yielding positive results The government's initiative, "All people unite to build cultural life," has been embraced enthusiastically by residents, reflecting a strong commitment to cultural development Notably, the percentage of households meeting cultural family standards rose from 78% in 1996, showcasing ongoing progress in the district's social policies.
West Lake, located in Tay Ho district, is home to 62 historical monuments, including 31 national monuments such as Tran Quoc Pagoda, Phu Tay Ho Van Nien Pagoda, and Uc Nien Pagoda This area also features the West Lake scenic area, one of the largest freshwater lakes in Hanoi, enhancing its cultural and natural significance.
526 ha area is considered the "lungs of the city"; Publicity and lake West Lake Water Park.
Current status of West Lake’s water quality
Water samples were taken from 9h30 to 10h30 on 17 th August 2015 at the edge of West Lake The samples were analyzed in the laboratory The results are shown in table 4.1.
Table 4.1 Analyzed results on water quality of West Lake
West Lake serves both tourism and business purposes, but its water quality is concerning, as it fails to meet the B2 standards Chemical, biological, and physical indicators exceed permissible limits, with turbidity levels being five times higher than the standard set by 02:2009/BYT Consequently, based on sample analysis and resident feedback, the water is deemed unsuitable for daily use by the local population.
Graph 4.1 Analyzed results of pH for West Lake’s water
As we can see, pH of West Lake’s water of all 3 samples are in the limits of levels of B1 and B2 of QCVN08
Sample 1 Sample 2 Sample 3 pH pH pHAverageLower limit QCVN 08Upper limit QCVN 08
Graph 4.2 Results of turbidity indicators in West Lake
The turbidity analysis indicates that the measured values exceed the standard set by 02:2009/BYT by more than five times, rendering this water unsuitable for the daily needs of the local population.
Graph 4.3 Results of COD indicators in West Lake
Turbidity Average Limit of QCVN 08
CODAverageLimit of QCVN 08
The COD indicators of water samples from West Lake are below the QCVN 08 standards, with the highest measurement recorded at only 12.5 mg/l in sample 1 In contrast, the permissible levels for QCVN 08 B1 and B2 range from 30 to 50 mg/l This indicates that the water quality in West Lake is acceptable.
Graph 4.4 Results of NH 4 + indicators in West Lake
With this table, the NH4 + indicators of water samples taken in West Lake are above of QCVN
The water quality indicators for purpose B1 and B2 reveal alarming results, with the lowest measurement at 7.21 mg/l, exceeding the permitted level of QCVN 08 by seven times The highest measurement reached 9.64 mg/l, which is over nine times the allowed limit These findings indicate severe pollution, rendering the water unsuitable for living purposes.
Graph 4.5 Results of PO 4 3- indicators in West Lake
The PO4 3- levels in West Lake are all below 0.1, indicating a very low concentration of phosphates in the water, which is a positive sign for the lake's health.
Graph 4.6 Results of TSS indicators in West Lake
TSSAverageLimit of QCVN 08
The Total Suspended Solids (TSS) indicators in West Lake are below the standards set by QCVN 08 for water usage categories B1 and B2 The maximum TSS level recorded is 53, which slightly exceeds the QCVN 08 level B1, indicating that the water quality in West Lake remains acceptable.
Graph 4.7 Results of coliform indicators in West Lake
In this table, the indicators about coliform show that this indicator at all the positions meet the standards of QCVN 08 B1 and QCVN 08 B2
Coliform Average Limit of QCVN 08
For TDS, the results analyzing water samples of West Lake show that this indicator atmeet the standards 38:2011/BTNMT and 39:2011/BTNMT
Graph 4.9 Results of BOD 5 indicators in West Lake
And the last indicator, BOD5, is also meet all the standards of QCVN 08 for purpose B1 and B2 of all 3 place
Major impacts of water contamination on the ecological functions and living quality
Table 4.2 Knowledge of people about water quality of West Lake
Knowledge about water quality of West Lake
The survey results indicate a general consensus that the water quality of West Lake is not clean, with a notable 25% of respondents unaware of its quality Additionally, a significant number of participants expressed concerns about severe pollution in West Lake.
BOD5AverageLimit of QCVN08
Table 4.3 Impacts affecting the water quality of West Lake Impacts that affecting the water quality of West Lake
Numbers of people know about it
People live near the lake 17 35.2
The survey indicates that a significant 35.2% of respondents believe that the behavior of residents near West Lake significantly impacts its water quality Additionally, 18.7% attribute pollution to the awareness levels of local businesses and individuals While some participants suggested that visitor activities and entertainment contribute to water quality issues, these are not seen as the primary causes The main concern lies with untreated wastewater from restaurants, boats, and residential areas that is directly discharged into the lake, posing a serious threat to its purity.
West Lake's severe pollution is primarily attributed to human actions and a lack of awareness Daily, the lake resembles a massive dumping ground as residents and visitors irresponsibly discard various types of waste Despite the presence of public trash bins, many individuals opt to throw their garbage directly into the water for convenience Additionally, the frequent use of bamboo poles for fishing contributes to the degradation of the lake's environment, exacerbating the pollution crisis.
The condition of West Lake is deteriorating due to the accumulation of waste from floating houses and restaurants, particularly around Thuy Khue Street in Tay Ho District, Hanoi Business owners appear to neglect the environmental impact of their activities, leading to a buildup of sludge, tobacco shells, cans, wrappers, and plastic waste This pollution not only produces unpleasant odors but also creates an environment conducive to the growth of dirt and bacteria, threatening local wildlife and the overall health of the lake.
Authorities have yet to take action regarding the pollution affecting West Lake, as residents like Ms Hong express concerns about the deteriorating water quality She notes that the introduction of floating yacht houses and the continuous expansion of nearby restaurants contribute to the unpleasant smell and increasing pollution in the lake.
Solutions
The thesis demonstrates that the water from West Lake is unsuitable for daily use by local residents due to declining water quality, driven by nearby operational activities and economic development To address this issue and improve the water quality of West Lake, several solutions are proposed.
4.4.1 Locations and characteristics of the waste generator discharged to West Lake
The residential area surrounding the lake encompasses Thuy Khue Street, Lac Long Quan Road, Au Co Road, Yen Phu Street, and Trich Sai Road It is essential to assess the location, population density, water quality standards, and the percentage of water waste in this region to ensure sustainable development and effective resource management.
The lake features three boats: the Taboo bar boat and the Tay Long 2 and Tay Long 3, which are utilized for tourism It is essential to assess the customer numbers, the effectiveness of wastewater treatment systems, and the interaction of these boats with the lake environment to ensure sustainable tourism practices.
In the vicinity of the lake, establishments like Maxx Coffee and Poseidon Coffee offer delightful dining experiences while prioritizing sustainability It is essential to explore how these restaurants manage wastewater and their interactions with the lake ecosystem, ensuring environmental responsibility in their operations.
The study reveals that individuals in the area engage in significant business activities without an adequate water treatment system, leading to littering around residential zones and West Lake Therefore, it is crucial to prioritize education aimed at raising awareness for environmental protection.
+ Organizing the contests to research about knowledge of environmental protection and West Lake water quality, create governmental agencies and community
+ Providing some educational contents about the awareness of environmental protection in schools and extracurricular meetings villages
4.4.3 Enhancing the management capacity of local authorities
Local authorities play a crucial role in community management, yet the effectiveness of management in the study area is hindered by the limited capacity of certain officials To address this issue, it is essential to focus on enhancing the leadership, expertise, and scientific knowledge of these officials through targeted training programs Additionally, organizing extracurricular meetings at the local level, featuring participation from experts and environmental organizations, can further support capacity building and improve community management.
The policies are to open the way for the project, the model is implemented smoothly,
In addition it helps to contribute, promote and replicate of the project
- The planning policies of using the cultivation land along the river, particularly forest land
- Preferential policies for organizations, households with actively participate in the environmental protection and development of forests
- Policies to support capitals and techniques to the infrastructural construction to protect the dike and river bank
- Policies on environmental management and forest management
Scientists emphasize the urgent need to upgrade the sewer system surrounding West Lake and other lakes in Hanoi to ensure the complete collection and prevention of wastewater runoff Implementing these improvements is crucial for restoring the lakes to their pristine condition reminiscent of the 1960s Additionally, these measures are essential for conserving the biodiversity of species within West Lake.
Preserving and conserving the green space around Westlake is a collective responsibility that extends beyond scientists and local authorities; it requires an increased awareness and active participation from the community to maintain the area's cleanliness and ecological health.
CONCLUSIONS 26 REFERENCES
From the time do the student thesis proposal, internship and do the field trips in the area of West Lake, this thesis proposal make clear some points:
The West Lake area is set to become the city's central hub, leading to a surge in business activities Consequently, the number of restaurants and cafes is rapidly rising, attracting more residents from other regions to settle in the area.
In addition, awareness of people to protect the lake is not good Those things make West Lake becomes more and more polluted
West Lake is being considered for B1 or B2 classification to enhance its appeal for tourism and business While certain chemical, biological, and physical indicators, such as pH and NH4+, slightly exceed the B1 and B2 standards, they remain within acceptable limits.
Generally, water quality of West Lake become polluted gradually because of business, waste water flow directly to the river, and bad awareness of people live around.