What are the criteria for judging the five categories of poor water quality?

1.Color. The quality of the water can be judged by the color.

2.Smell. You can tell by the smell.

3.Taste. Drinking water can be judged.

Comprehensive Water Quality Labelling Index (WQI).

In 2006, the third round of Shanghai's three-year action plan for environmental protection took pollution interception and control as the fundamental measure, and continued to deepen the comprehensive improvement of the city-managed rivers in the central urban area and the backbone rivers in the suburbs. According to the Technical Specifications for Routine Evaluation of Water Quality of Inland Rivers and Water Systems in Shanghai (Trial), the comprehensive water quality identification index is used as the assessment index. On the basis of a comprehensive analysis of the pollution status of various types of water quality indicators, the comprehensive water quality identification index method selects representative key pollution factors, combines the functional zone standards of each water body, and calculates a comprehensive coefficient, i.e., the water quality identification index, to reflect the water quality status of the river.

The Comprehensive Water Quality Labelling Index (WQI) consists of integer places, three or four significant decimal places:

wqi = where: wqi — Composite Water Quality Labelling Index;

x1 — Integrated water quality level;

x2 — The position of the composite water quality in the water quality change interval of the grade, calculated and determined according to the formula according to the principle of rounding;

x3 — the number of individual water quality indicators participating in the comprehensive water quality assessment, which are inferior to the water environment functional zone target;

x4 — Comparison of the comprehensive water quality category with the water function zone category, depending on the pollution level of the comprehensive water quality, x4 is one or two significant digits.

The comprehensive water quality labeling index generally includes two parts: first, the comprehensive water quality index, which is calculated from the comprehensive water quality labeling index; Second, the identification code is x3 and x4 in the comprehensive water quality identification index, which is obtained by judgment on the basis of obtaining the comprehensive water quality index.

The criteria for judging the comprehensive water quality level evaluation are shown in Table 1.

Comprehensive water quality level evaluation.

The judgment is based on the comprehensive water quality level.

Kind. Inferior and black and smelly.

Note: This is the Composite Water Quality Index.

The qualitative evaluation criteria for comprehensive water quality are shown in Table 2.

Qualitative evaluation basis for water quality.

Judgment Criteria Qualitative evaluation conclusions.

x2 is not 0 x2 is 0

f- x1 1 f- x1-1 1 excellent.

x1=f x1-1=f Good.

x1-f=1 x1-f-1=1 Mild contamination.

x1-f=2 x1-f-1=2 Moderately polluted.

X1-F 3 X1-F-1 3 Heavily Polluted.

Note 1: x1 is an integer of the Comprehensive Water Quality Labelling Index.

Note 2: x2 is the first decimal place of the CWI Index.

Note 3: F is the category of water functional area.

The four categories of water quality standards are based on agricultural and industrial water requirements. In addition to being suitable for agricultural and some industrial water, it can be used as domestic drinking water after proper treatment.

According to the current status of groundwater quality, human health benchmark value and groundwater quality protection objectives in China, and with reference to the highest requirements of domestic drinking water, industrial and agricultural water quality, groundwater quality is divided into five categories. They are:

1. Class It mainly reflects the natural low background content of groundwater chemical components. Suitable for a variety of uses;

2. Class It mainly reflects the natural background content of groundwater chemical components. Suitable for a variety of uses;

3. Category is based on the benchmark value of human health. It is mainly suitable for centralized drinking water sources and industrial and agricultural water;

4. Category is based on agricultural and industrial water requirements. In addition to being suitable for agricultural and some industrial water, it can be used as domestic drinking water after proper treatment.

5. Category is not suitable for drinking, and other water can be selected according to the purpose of use.

Legal basis

Water Law of the People's Republic of China

Article 32 The competent administrative departments of water resources, in conjunction with the administrative departments of environmental protection, relevant departments and the people of relevant provinces, autonomous regions and municipalities directly under the Central Government, shall, in accordance with the comprehensive planning of river basins, water resources protection planning and the requirements of economic and social development, draw up the water function zoning of important rivers and lakes determined by the State, and report them for approval. The water function zoning of other rivers and lakes across provinces, autonomous regions and municipalities directly under the Central Government shall be formulated by the relevant river basin management agencies in conjunction with the people's water administrative departments, environmental protection administrative departments and other relevant departments of the provinces, autonomous regions and municipalities directly under the Central Government where the rivers and lakes are located, and shall be reviewed and approved by the water administrative departments of the relevant provinces, autonomous regions and municipalities directly under the Central Government in conjunction with the administrative departments of environmental protection, and shall be submitted to the competent departments or their authorized departments for approval.

The water function zoning of rivers and lakes other than those provided for in the preceding paragraph shall be drafted by the local people's water administrative departments at or above the county level in conjunction with the people's environmental protection administrative departments and relevant departments at the same level, and shall be submitted to the people's departments at the same level or their authorized departments for approval, and shall be reported to the water administrative departments at the next higher level and the administrative departments of environmental protection for the record.

The people's water administrative departments at or above the county level or river basin management agencies shall, in accordance with the requirements of the water function zone for water quality and the natural purification capacity of the water body, verify the pollutant-holding capacity of the waters, and submit opinions to the administrative departments for environmental protection on limiting the total amount of pollutant discharge in the waters.

The local people's water administrative departments and river basin management agencies at or above the county level shall monitor the water quality status of the water function area, and if it is found that the total discharge of key pollutants exceeds the control index, or the water quality of the water function area does not meet the requirements of the water quality function, it shall promptly report to the relevant people to take governance measures and notify the administrative department of environmental protection.

The quality of water flush balance in China is classified as: I, II, III, IV, V and inferior V, a total of five categories.

Class 1 water quality: good water quality. Groundwater only needs to be disinfected, and surface water can be used for drinking after simple purification (such as filtration) and disinfection.

Class II water quality: The water quality is slightly polluted. After conventional purification treatment (such as flocculation, sedimentation, filtration, disinfection, etc.), the water quality can be used for domestic drinking.

Class III water quality: It is suitable for the second-level protection zone of centralized drinking water sources, general fish protection area and swimming area.

Four types of water quality: suitable for general industrial protection areas and recreational water areas that are not in direct contact with the human body.

Category 5 water quality: It is applicable to the agricultural water use area and the water area with general landscape requirements, and exceeds the water quality standard of the five categories.

The body of water is basically useless.

The environmental quality standards for surface water are divided into five categories: class, class water quality, class water quality, class water quality, and class water quality.

1. The class is mainly applicable to source water and national nature reserves.

2. It is mainly suitable for first-class protection areas of centralized surface water sources of domestic drinking water, habitats of rare aquatic organisms, fish and shrimp production grounds, and feeding grounds for juvenile fish.

3. It is mainly applicable to fishery waters and swimming areas such as centralized drinking water surface water source secondary protection areas, fish and shrimp wintering grounds, migratory channels, aquaculture areas, etc.

4. It is mainly applicable to general industrial water areas and recreational water areas that are not in direct contact with the human body.

5. The category is mainly applicable to agricultural water areas and general landscape requirements of waters.

Legal basis: "Surface Water Environmental Quality Standards" (GB3838-2002) 3The classification of water functions and standards is divided into five categories according to the environmental functions and protection objectives of surface water waters. Category I is mainly applicable to source water and national nature reserves;

Category I is mainly suitable for first-class protection areas of centralized surface water sources of domestic drinking water, habitats of rare aquatic organisms, spawning grounds for fish and shrimp, and feeding grounds for juvenile fish.

It is mainly suitable for fishery waters and swimming areas such as centralized domestic drinking water surface water source secondary protection areas, fish and shrimp wintering grounds, swimming channels, aquaculture areas, etc.;

Class V is mainly applicable to general industrial water areas and recreational water areas that are not in direct contact with the human body;

Category V is mainly applicable to agricultural water use areas and waters with general landscape requirements.

Corresponding to the above-mentioned five types of water functions of surface water, the standard values of the basic items of surface water environmental quality standards are divided into five categories, and the standard values of the corresponding categories are implemented for different functional categories. The standard value of the higher water function category is stricter than the lower standard value of the water function category. If the same water area has multiple types of functions, the standard value corresponding to the highest functional category shall be performed.

The realization of water function and the achievement of functional category standards have the same meaning.

Category: Mainly applicable to source water, national nature reserves;

Category: Mainly suitable for centralized drinking water, surface water source first-class protection area, rare aquatic organisms habitat, fish and shrimp spawning grounds, juvenile fish feeding grounds, etc.;

Category: Mainly suitable for centralized drinking water, surface water source secondary protection area, fish and shrimp wintering, return channel, aquaculture area and other fishery waters and swimming areas;

Category: Mainly suitable for general industrial water areas and recreational water areas that are not in direct contact with the human body;

Category: Mainly applicable to agricultural water use areas and general landscape requirements of waters.

Water Quality Monitoring:

All regions should conduct regular testing of groundwater quality. The test method shall be implemented in accordance with the national standard GB 5750 "Standard Inspection Method for Drinking Water".

Local groundwater monitoring departments shall set up monitoring points in groundwater areas of different quality categories for water quality monitoring, and the frequency of monitoring shall not be less than twice a year (in the wet and dry periods).

The monitoring items are: pH, ammonia nitrogen, nitrate, nitrite, volatile phenols, cyanide, arsenic, mercury, chromium (hexavalent), total hardness, lead, fluorine, cadmium, iron, manganese, total dissolved solids, permanganate index, sulfate, chloride, coliforms, and other items that reflect major water quality problems in the region.

The above content reference:

It is classified according to the chemical composition of groundwater, and classified in accordance with the "Environmental Quality Standards for Surface Water".

Specific classification methods:

The four evaluation methods commonly used in the comprehensive evaluation of groundwater quality: single factor evaluation method, F-value scoring method, fuzzy comprehensive evaluation method and gray correlation analysis method, taking the detection data of groundwater quality samples in the main mining horizon as an example, the above four evaluation methods are used to comprehensively evaluate the quality of groundwater quality samples, and then compare and comprehensively analyze the evaluation results of different evaluation methods.

The results show that although the single-factor evaluation method cannot reflect the actual water quality of the water body, it can directly reflect the degree of exceedance of each individual index in the water quality sample, and can obviously determine the main pollution index. The F-value scoring method can accurately reflect the actual water quality status only when there is a clear classification of various individual indicators, and there are more or no over-standard indicators, but it highlights the most serious pollution index level. However, the fuzzy comprehensive evaluation method and the grey correlation analysis method can make more scientific and effective use of the detection data of water quality samples, and eliminate the shortcomings of using the simple evaluation method that can only use one numerical index value as the dividing line.

Five categories of surface moisture in China:

Class I water quality: mainly applicable to source water, national nature reserves.

Class II water quality: It is mainly suitable for centralized domestic drinking water, first-class protection areas of surface water sources, habitats of rare aquatic organisms, spawning grounds for fish and shrimp, and feeding grounds for juvenile fish.

Three types of water quality: It is mainly suitable for centralized domestic drinking water, secondary protection areas of surface water sources, fish and shrimp wintering and return channels, aquaculture areas and other fishery waters and swimming areas.

Four types of water quality: mainly suitable for general industrial water areas and recreational water areas that are not in direct contact with the human body;

Five types of water quality: Mainly suitable for agricultural water use areas and general landscape requirements of water.

Specific indicators of inferior five types of water quality: dissolved oxygen concentration (DO) = 15, ammonia nitrogen concentration (NH3-N) >=, pH value 6-9.

The items involved in the standards of the inferior five types of water shed materials include nutrient salt cations, suspended solids, microbial pollution, organic pollutants, heavy metal anions, disinfection by-products, etc.

The Inferior Category 5 water quality standards apply to all kinds of water environments, artificial rivers and lakes, artificial lakes and marshes and other water systems, as well as water systems used by humans, including industrial production water, mining water, groundwater, agricultural irrigation water, etc.

Water Quality Classification Concept:

Class (Class I surface water) is mainly applicable to source water and national nature reserves.

Class II surface water is mainly suitable for first-class protection areas of centralized domestic drinking water surface water sources, habitats of rare aquatic organisms, fish and shrimp production grounds, and bait grounds for juvenile fish.

Class III surface water is mainly suitable for fishery waters and swimming areas such as centralized domestic drinking water surface water sources, secondary protection areas, fish and shrimp wintering grounds, migratory passages, aquaculture areas, etc.

Class (four types of surface water) is mainly applicable to general industrial water use areas and recreational water areas that are not in direct contact with the human body.

Class (five types of surface water) is mainly suitable for agricultural water use areas and general landscape water areas. <>