A method for evaluating water supply safety factor

Abstract

The invention relates to the technical field of water resource safety assessment, and discloses a water supply safety factor assessment method, comprising the following steps: determining a research area and an assessment level year for water supply safety factor assessment, and obtaining assessment data of the research area in the assessment level year; judging whether there is hydraulic connection between surface water source projects in the research area, and if there is hydraulic connection, calculating the repeated calculation amount of water supply capacity of the surface water source projects in the research area; calculating the water supply capacity of the surface water source projects in the research area; calculating the effective water supply capacity of the research area; calculating the water supply safety factor of the research area in the assessment level year; constructing a water supply safety factor safety assessment standard, and determining the safety level of the water supply safety factor of the research area in the assessment level year; the method improves the accuracy of water supply safety analysis and the reliability of water supply capacity analysis in the research area by introducing the water supply safety factor to conduct safety assessment on the regional water supply system.

Description

Technical Field

[0001] The present invention relates to the technical field of water resource safety assessment, and in particular to a method for evaluating a water supply safety factor. Background Art

[0002] In traditional water resource allocation, the water supply capacity of water supply infrastructure is an important basis for analyzing the available water supply. In order to prevent the water supply infrastructure system from being unable to function normally and causing a water supply crisis when facing extreme climate events or emergencies, the concept of water supply safety factor is introduced to reflect the resilience of the urban and rural water supply infrastructure system, especially its adaptability to special situations such as drought years, consecutive drought years or sudden water pollution events.

[0003] The water supply safety coefficient refers to the ratio of effective water supply capacity to water consumption within a certain area, reflecting the overall degree of urban and rural water supply security. Among them, the effective water supply capacity refers to the part of the water supply capacity that does not include groundwater over-exploitation and ecological water use in the river, reflecting the overall water supply capacity of water conservancy projects under the premise of ensuring the health of the river ecosystem.

[0004] Although rainfall is relatively abundant in the karst mountainous areas, water resources are unevenly distributed in time and space, making them difficult to develop and utilize. Affected by the special topography and landforms, they are prone to droughts and often alternate between drought and floods. The construction of the water supply infrastructure system faces many difficulties, such as high fields and low water content, poor water storage and retention capacity, and unfavorable conditions for large reservoirs. Engineering water shortage has become a prominent shortcoming that restricts economic and social development.

[0005] Compared with plain areas, karst mountainous areas are mainly supplied by surface water sources. The special topography has a significant impact on the scale and structure of the water supply capacity of surface water source projects, which is mainly reflected in the decentralized construction of most water supply projects, insufficient water supply from backbone water sources, a large proportion of water diversion and lifting projects, low water source guarantee rate, and some unconventional water sources still have water supplied by non-water supply projects. Therefore, the particularity of karst mountainous areas needs to be fully considered in the evaluation of water supply safety factors.

[0006] Although water supply safety factors are occasionally mentioned in national and local plans for water conservancy development, water security, and water network construction, there is no unified concept or calculation method for water supply safety factors, no recognized standard for safety evaluation levels, and a lack of specialized research on the particularities of water supply safety factors in karst mountainous areas. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention provides a method for evaluating water supply safety factor.

[0008] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0009] A water supply safety factor evaluation method comprises the following steps:

[0010] S1. Determine the research area and evaluation level year for water supply safety factor evaluation, and obtain the evaluation data of the research area in the evaluation level year;

[0011] S2. Based on the evaluation data of the study area in the evaluation level year obtained in step S1, determine whether there is a hydraulic connection between the surface water source projects in the study area. If there is a hydraulic connection, calculate the repeated calculation amount of the water supply capacity of the surface water source projects in the study area;

[0012] S3, calculating the water supply capacity of the surface water source project in the study area according to the repeated calculation amount of the water supply capacity of the surface water source project in the study area calculated in step S2 and the evaluation data of the study area in the evaluation level year obtained in step S1;

[0013] S4, calculating the effective water supply capacity of the study area according to the evaluation data of the study area in the evaluation level year obtained in step S1 and the water supply capacity of the surface water source project in the study area calculated in step S3;

[0014] S5. Calculate the water supply safety factor of the study area in the evaluation level year according to the annual water consumption of the study area and the effective water supply capacity of the study area calculated in step S4;

[0015] S6. Construct a safety evaluation standard for water supply safety factor, and determine the safety level of the water supply safety factor of the study area calculated in step S5 in the evaluation level year.

[0016] Furthermore, step S1 specifically includes:

[0017] Determine the research area and evaluation level year for water supply safety factor evaluation, where the evaluation level year includes the current level year and the planned level year, specifically:

[0018] If the evaluation level year is the current level year, the evaluation data of the current level year including the development and utilization of water resources, water supply infrastructure and river and lake ecosystem conditions shall be obtained;

[0019] Among them, the development and utilization of water resources include the annual water consumption and water supply structure of the study area;

[0020] The water supply infrastructure includes the number, scale, location and designed annual water supply capacity of surface water source projects, groundwater source projects and unconventional water sources in the study area. Surface water source projects include water storage projects and water diversion and lifting projects. Water diversion and lifting projects include water diversion projects, water lifting projects and water diversion projects.

[0021] Among them, the status of river and lake ecosystems includes the amount of ecological water use squeezed out of rivers and groundwater overexploitation in the study area;

[0022] If the evaluation level year is the planning level year, then the evaluation data for the planning level year shall include the development and utilization of water resources, water supply infrastructure, and river and lake ecosystem conditions, as well as evaluation data on the target requirements for total water use control, groundwater over-exploitation management, limited and reduced extraction, and river and lake ecological flow protection, as well as water demand forecast results.

[0023] Furthermore, step S2 specifically includes:

[0024] S21, according to the evaluation data of the surface water source projects in the evaluation data of the study area in the evaluation level year obtained in step S1, obtain the spatial relationship between the surface water source projects, and judge whether there is a hydraulic connection between the surface water source projects, such as upstream and downstream, and inflow and outflow. If so, execute step S22, otherwise, execute step S23;

[0025] Among them, hydraulic connection refers to the relationship between water supply and discharge between surface water source projects;

[0026] S22. Calculate the repeated calculation of the water supply capacity of the surface water source projects in the study area, that is:

[0027]

[0028] Among them, D s represents the repeated calculation of the water supply capacity of the surface water source project in the study area, o represents the number of locations where the surface water source project has hydraulic connection in the study area, and D sk It represents the repeated calculation of the water supply capacity of the surface water source project with hydraulic connection at the kth position in the study area under the average water inflow over many years;

[0029] S23. The repeated calculation of water supply capacity of surface water source projects in the study area is 0.

[0030] Furthermore, step S3 specifically includes:

[0031] According to the repeated calculation of the water supply capacity of the surface water source project in the study area calculated in step S2 and the scale of the water storage project and the water diversion and water transfer project in the evaluation data of the study area in the evaluation level year obtained in step S1, the water supply capacity adjustment coefficient is set to calculate the water supply capacity of the surface water source project in the study area, that is:

[0032]

[0033] Among them, C s represents the water supply capacity of the surface water source project in the study area under the average water inflow over many years, m represents the number of scale levels of the water storage project, C ri represents the water supply capacity of the water storage project of scale i in the study area under the average water inflow over many years, αri represents the water supply capacity adjustment coefficient of the water storage project with scale i in the study area, n represents the number of scale levels of water diversion and lifting projects, C dj represents the water supply capacity of the water diversion project of scale j in the study area under the average water inflow over many years, β dj It represents the water supply capacity adjustment coefficient of the water diversion project with a scale of j in the study area.

[0034] Furthermore, the specific process of setting the water supply capacity adjustment coefficient is as follows:

[0035] The larger the scale of the surface water source project, the smaller the impact of the topography of the study area on the water supply capacity of the surface water source project, and the larger the water supply capacity adjustment coefficient of the surface water source project is set. When the topography of the study area has no impact on the water supply capacity of the surface water source project, the water supply adjustment coefficient is set to 1.

[0036] Furthermore, step S4 specifically includes:

[0037] According to the water supply capacity of groundwater source projects, water supply capacity of unconventional water sources, groundwater overexploitation, ecological water use in rivers in the evaluation data of the study area in the evaluation level year obtained in step S1, and the water supply capacity of surface water source projects in the study area calculated in step S3, the effective water supply capacity of the study area is calculated, that is:

[0038] C w =C s +C g +C n -W go -W eo

[0039] Among them, C w represents the effective water supply capacity of the study area, C g Indicates the water supply capacity of the groundwater source project, C n Indicates the water supply capacity of unconventional water sources, W go represents the amount of groundwater overdraft, W eo Indicates the amount of ecological water usage in the river.

[0040] Furthermore, step S5 specifically includes:

[0041] According to the annual water consumption of the study area and the effective water supply capacity of the study area calculated in step S4, the water supply safety factor of the study area in the evaluation level year is calculated, that is:

[0042]

[0043] Among them, P represents the water supply safety factor of the study area in the evaluation level year, W urepresents the annual water consumption in the study area.

[0044] Furthermore, the annual water consumption in the study area is:

[0045] If the evaluation level year is the current level year, the annual water consumption of the study area is the annual water consumption of the study area in the current level year;

[0046] If the evaluation level year is the planning level year, the annual water consumption of the study area is calculated using the following formula:

[0047]

[0048] Among them, W d W represents the total water demand of the study area under the multi-year average water inflow in the planning level year. r It represents the total water consumption control index value of the study area in the planning level year.

[0049] Furthermore, step S6 specifically includes:

[0050] S61. Classify the water supply safety factor into safety levels and establish a water supply safety factor evaluation standard, specifically:

[0051] When S ≥ 1.8, the water supply in the study area is safe;

[0052] When 1.5≤S<1.8, the water supply in the study area is safe;

[0053] When 1.0≤S<1.5, the water supply in the study area is basically safe;

[0054] When 0.85≤S<1.0, the water supply in the study area is unsafe;

[0055] When S < 0.85, the water supply in the study area is extremely unsafe;

[0056] S62. According to the water supply safety factor evaluation standard constructed in step S61, determine the safety level of the water supply safety factor of the study area calculated in step S5 in the evaluation level year.

[0057] The present invention has the following beneficial effects:

[0058] A water supply safety factor evaluation method proposed in the present invention introduces a water supply safety factor to improve the adaptability and resilience of the water supply infrastructure system; conducts a safety evaluation of the regional water supply system by calculating the water supply safety factor to improve the accuracy of the water supply safety analysis in the study area; and sets a water supply capacity adjustment coefficient to improve the reliability of the water supply capacity analysis in the study area. The method has good operability and replicability, and realizes an objective evaluation of the water supply safety status in the study area, so as to be used for the water supply capacity and supply-demand balance analysis in the study area in water resources allocation. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 The figure is a flow chart of a water supply safety factor evaluation method proposed in the present invention. DETAILED DESCRIPTION

[0060] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0061] like Figure 1 As shown, a water supply safety factor evaluation method includes the following steps S1-S6:

[0062] S1. Determine the research area and evaluation level year for water supply safety factor evaluation, and obtain the evaluation data of the research area in the evaluation level year.

[0063] In this embodiment, the study area is a karst mountain area, and relevant evaluation data of the study area in the evaluation level year are obtained so as to be used in the subsequent steps to calculate the water supply safety factor.

[0064] Specifically, step S1 includes:

[0065] Determine the research area and evaluation level year for water supply safety factor evaluation, where the evaluation level year includes the current level year and the planned level year, specifically:

[0066] If the evaluation level year is the current level year, then the evaluation data for the current level year shall include the development and utilization of water resources, water supply infrastructure, and river and lake ecosystem conditions.

[0067] Among them, the development and utilization of water resources include the annual water consumption and water supply structure in the study area.

[0068] Among them, the water supply infrastructure situation includes the number, scale, location and designed annual water supply capacity of surface water source projects, groundwater source projects and unconventional water sources in the study area. Surface water source projects include water storage projects and water diversion and regulation projects. Water diversion and regulation projects include water diversion projects, water lifting projects and water diversion projects.

[0069] Among them, the status of river and lake ecosystems includes the amount of ecological water usage in rivers and the amount of groundwater over-exploitation in the study area.

[0070] If the evaluation level year is the planning level year, then the evaluation data for the planning level year shall include the development and utilization of water resources, water supply infrastructure, and river and lake ecosystem conditions, as well as evaluation data on the target requirements for total water use control, groundwater over-exploitation management, limited and reduced extraction, and river and lake ecological flow protection, as well as water demand forecast results.

[0071] S2. Based on the evaluation data of the study area in the evaluation level year obtained in step S1, determine whether there is a hydraulic connection between the surface water source projects in the study area. If there is a hydraulic connection, calculate the repeated calculation amount of the water supply capacity of the surface water source projects in the study area.

[0072] In this embodiment, if there is no hydraulic connection between surface water source projects, the sum of the water supply capacities of individual surface water source projects is the water supply capacity of the surface water source projects in the study area, that is, there are no duplicate calculation items in the regional water supply capacity; if there is a hydraulic connection between surface water source projects, the sum of the water supply capacities of individual surface water source projects is the water supply capacity of the surface water source projects in the study area. Before that, the surface water source projects in the study area are analyzed to deduct the duplicate calculation items in the water supply capacity of the surface water source projects in the study area.

[0073] Specifically, step S2 specifically includes S21-S23:

[0074] S21. Based on the evaluation data of surface water source projects in the evaluation data of the study area in the evaluation level year obtained in step S1, obtain the spatial relationship between the surface water source projects, and determine whether there is hydraulic connection between the surface water source projects in terms of upstream and downstream, inflow and outflow. If so, execute step S22; otherwise, execute step S23; wherein the hydraulic connection is the relationship between water supply and discharge between surface water source projects.

[0075] In this embodiment, information such as the location and water supply direction of each surface water source project can be obtained from the evaluation data, and the spatial relationship between the surface water source projects can be obtained by using the geographic information system.

[0076] S22. Calculate the repeated calculation of the water supply capacity of the surface water source projects in the study area, that is:

[0077]

[0078] Among them, D s represents the repeated calculation of the water supply capacity of the surface water source project in the study area, o represents the number of locations where the surface water source project has hydraulic connection in the study area, and D sk It represents the repeated calculation of the water supply capacity of the surface water source project with hydraulic connection at the kth position in the study area under the average water inflow over many years.

[0079] In this embodiment, D s The unit is 100 million m3 , D sk The unit is 100 million m 3 .

[0080] S23. The repeated calculation of water supply capacity of surface water source projects in the study area is 0.

[0081] S3. Calculate the water supply capacity of the surface water source projects in the study area based on the repeated calculation of the water supply capacity of the surface water source projects in the study area calculated in step S2 and the evaluation data of the study area in the evaluation level year obtained in step S1.

[0082] In this embodiment, the impact of the topography and landforms of the study area, i.e., the karst mountain area, on the water supply capacity of the surface water source project is related to the scale of the surface water source project. The larger the scale, the stronger its ability to resist drought, and the less its water supply capacity is affected by the topography of the karst mountain area. On the contrary, small water source projects such as ponds, cellars, and small reservoirs are very likely to dry up completely or the water level will drop when encountering drought, which seriously affects their water supply capacity. Therefore, according to the type and scale of the surface water source project, the water supply capacity adjustment coefficient of the surface water source project is set to more objectively characterize the water supply capacity of surface water source projects of different types and scales that are adapted to the characteristics of the karst mountain area.

[0083] Specifically, step S3 includes:

[0084] According to the repeated calculation of the water supply capacity of the surface water source project in the study area calculated in step S2 and the scale of the water storage project and the water diversion and water transfer project in the evaluation data of the study area in the evaluation level year obtained in step S1, the water supply capacity adjustment coefficient is set to calculate the water supply capacity of the surface water source project in the study area, that is:

[0085]

[0086] Among them, C s represents the water supply capacity of the surface water source project in the study area under the average water inflow over many years, m represents the number of scale levels of the water storage project, C ri represents the water supply capacity of the water storage project of scale i in the study area under the average water inflow over many years, α ri represents the water supply capacity adjustment coefficient of the water storage project with scale i in the study area, n represents the number of scale levels of water diversion and lifting projects, C dj represents the water supply capacity of the water diversion project of scale j in the study area under the average water inflow over many years, β dj It represents the water supply capacity adjustment coefficient of the water diversion project with a scale of j in the study area.

[0087] In this embodiment, the water supply capacity adjustment coefficient is set according to the project scale and the characteristics of the karst mountain area.s The unit is 100 million m 3 , C ri The unit is 100 million m 3 , C dj The unit is 100 million m 3 .

[0088] Specifically, the specific process of setting the water supply capacity adjustment coefficient is:

[0089] The larger the scale of the surface water source project, the smaller the impact of the topography of the study area on the water supply capacity of the surface water source project, and the larger the water supply capacity adjustment coefficient of the surface water source project is set. When the topography of the study area has no impact on the water supply capacity of the surface water source project, the water supply adjustment coefficient is set to 1, specifically:

[0090] The scale of the water storage project is a storage capacity greater than or equal to 1 billion m 3 When the water supply capacity adjustment coefficient of the water storage project is 1, the scale of the water diversion project is that the annual water diversion volume is greater than or equal to 1 billion m 3 When the water supply capacity adjustment coefficient of the water diversion and lifting project is 1;

[0091] The scale of the water storage project is a storage capacity greater than or equal to 1 and less than 1 billion m 3 When the water supply capacity adjustment coefficient of the water storage project is 1, the scale of the water diversion project is that the annual water diversion volume is greater than or equal to 3 and less than 1 billion m 3 When the water supply capacity adjustment coefficient of the water diversion and lifting project is 1;

[0092] The scale of the water storage project is a storage capacity greater than or equal to 0.1 and less than 100 million m 3 When the water supply capacity adjustment coefficient of the water storage project is 0.95, the scale of the water diversion project is that the annual water diversion volume is greater than or equal to 1 and less than 300 million m 3 When the water supply capacity adjustment coefficient of the water diversion and lifting project is 0.95;

[0093] The scale of the water storage project is a storage capacity greater than or equal to 0.01 and less than 0.1 billion m 3 When the water supply capacity adjustment coefficient of the water storage project is 0.9, the scale of the water diversion project is that the annual water diversion volume is greater than or equal to 0.3 and less than 100 million m 3 When the water supply capacity adjustment coefficient of the water diversion and lifting project is 0.9;

[0094] The scale of the water storage project is a storage capacity greater than or equal to 0.001 and less than 0.01 billion m 3 When the water supply capacity adjustment coefficient of the water storage project is 0.85, the scale of the water diversion project is that the annual water diversion volume is greater than or equal to 0.1 and less than 0.3 billion m 3 When the water supply capacity adjustment coefficient of the water diversion and lifting project is 0.85;

[0095] The scale of the water storage project is less than 0.001 billion m 3 When the water supply capacity adjustment coefficient of the water storage project is 0.8, the scale of the water diversion and lifting project is less than 100 million m3 of water per year. 3 At this time, the water supply capacity adjustment coefficient of the water diversion project is 0.8.

[0096] In this embodiment, the water supply capacity adjustment coefficient of the surface water source project in the karst mountain area is set, as shown in Table 1:

[0097] Table 1 Water supply capacity adjustment coefficient of surface water source projects in karst mountainous areas

[0098]

[0099] S4. Calculate the effective water supply capacity of the study area based on the evaluation data of the study area in the evaluation level year obtained in step S1 and the water supply capacity of the surface water source project in the study area calculated in step S3.

[0100] In this embodiment, the effective water supply capacity of the study area includes the water supply capacity of surface water source projects, groundwater source projects, and unconventional water sources, excluding the part occupied by groundwater over-exploitation and ecological water use in the river.

[0101] Specifically, step S4 includes:

[0102] According to the water supply capacity of groundwater source projects, water supply capacity of unconventional water sources, groundwater overexploitation, ecological water use in rivers in the evaluation data of the study area in the evaluation level year obtained in step S1, and the water supply capacity of surface water source projects in the study area calculated in step S3, the effective water supply capacity of the study area is calculated, that is:

[0103] C w =C s +C g +C n -W go -W eo

[0104] Among them, C w represents the effective water supply capacity of the study area, C g Indicates the water supply capacity of the groundwater source project, C n Indicates the water supply capacity of unconventional water sources, W go represents the amount of groundwater overdraft, W eo Indicates the amount of ecological water usage in the river.

[0105] In this embodiment, C w The unit is 100 million m 3 , C g The unit is 100 million m3 , C n The unit is 100 million m 3 , W go The unit is 100 million m 3 , W eo The unit is 100 million m 3 .

[0106] S5. Calculate the water supply safety factor of the study area in the evaluation level year based on the annual water consumption of the study area and the effective water supply capacity of the study area calculated in step S4.

[0107] Specifically, step S5 includes:

[0108] According to the annual water consumption of the study area and the effective water supply capacity of the study area calculated in step S4, the water supply safety factor of the study area in the evaluation level year is calculated, that is:

[0109]

[0110] Among them, P represents the water supply safety factor of the study area in the evaluation level year, W u represents the annual water consumption in the study area.

[0111] In this embodiment, W u The unit is 100 million m 3 .

[0112] Specifically, the annual water consumption in the study area is:

[0113] If the evaluation level year is the current level year, the annual water consumption of the study area is the annual water consumption of the study area in the current level year.

[0114] If the evaluation level year is the planning level year, the annual water consumption of the study area is calculated using the following formula:

[0115]

[0116] Among them, W d W represents the total water demand of the study area under the multi-year average water inflow in the planning level year. r It represents the total water consumption control index value of the study area in the planning level year.

[0117] In this embodiment, W d The unit is 100 million m 3 , W r The unit is 100 million m 3 .

[0118] In this embodiment, when the total water demand is less than the total water consumption control index value, the annual water consumption of the study area is the total water demand; when the total water demand is greater than or equal to the total water consumption control index value, the annual water consumption of the study area is the total water consumption control index value to meet the requirements of the most stringent water resources management or water resources rigid constraint system.

[0119] S6. Construct a safety evaluation standard for water supply safety factor, and determine the safety level of the water supply safety factor of the study area calculated in step S5 in the evaluation level year.

[0120] Specifically, step S6 specifically includes S61-S62:

[0121] S61. Based on the data distribution of the ratio of water supply capacity to annual water consumption in various provinces across the country, the water supply safety factor is divided into safety levels and the water supply safety factor evaluation standard is constructed, which is as follows:

[0122] When S ≥ 1.8, the water supply in the study area is safe.

[0123] When 1.5≤S<1.8, the water supply in the study area is safe.

[0124] When 1.0≤S<1.5, the water supply in the study area is basically safe.

[0125] When 0.85≤S<1.0, the water supply in the study area is unsafe.

[0126] When S<0.85, the water supply in the study area is extremely unsafe.

[0127] S62. According to the water supply safety factor evaluation standard constructed in step S61, determine the safety level of the water supply safety factor of the study area calculated in step S5 in the evaluation level year.

[0128] When the calculated water supply safety factor P of the study area in the evaluation level year is in the corresponding interval of the constructed water supply safety factor evaluation standard S, the safety level of the water supply safety factor of the study area in the evaluation level year is obtained.

[0129] In this embodiment, taking Zunyi City, Guizhou Province as an example, the evaluation level year is selected as the current level year 2021, and a water supply safety factor evaluation method proposed in the present invention is used for experiments. Zunyi City is located at the junction of Guizhou, Chongqing and Sichuan provinces. The terrain is high in the west and low in the east, high in the middle and low in the north and south. The Dalou Mountain Range stretches from southwest to northeast, with an altitude of generally 1000 to 1600m. There are more mountains and fewer plains. Mountains account for 61.9%, inter-mountain plains and river valley basins account for 7.4%, and hills account for 30.7%. Karst landforms account for 75% of the city's land area, forming more ridge valleys, gentle hill valleys, peaks and valleys, and valleys from mountains. Affected by factors such as topography, high mountains and low water, and uneven temporal and spatial distribution of water resources, the water supply security guarantee capacity is insufficient, and it is one of the areas in Guizhou Province with serious engineering water shortages. By the end of 2021, Zunyi City has built water supply projects covering county towns, industrial and agricultural parks, most townships and rural safe drinking water projects. The total water supply in the city in 2021 is 2.386 billion m 3 , of which the water supply from surface water sources, groundwater sources and unconventional water sources were 2.352 billion m 3 (accounting for 98.6%), 13 million m 3 , 210 million m 3 Of the water supply from surface water sources, 60.8% comes from water storage projects, and 39.2% comes from water diversion and water transfer projects. All the water supply from groundwater sources is shallow groundwater. The water supply from unconventional water sources is mainly recycled water.

[0130] The spatial relationship analysis of surface water source projects was carried out through the geographic information system (ArcGIS). At present, there are three water supply projects with hydraulic connection, including Nanjiao Reservoir, Beijiao Reservoir and Tianmenhe Reservoir. Therefore, the subtotal of repeated calculation of water supply capacity of surface water source projects in Zunyi City is 16 million m 3 .

[0131] Without considering the impact of karst mountain topography on the water supply capacity of surface water source projects and the repeated calculation of the water supply capacity of surface water source projects, the number and water supply capacity of water storage projects and water diversion projects of different scales in Zunyi City are shown in Table 2. After deducting the repeated calculation of the water supply capacity of surface water source projects, the water supply capacity of surface water source projects is 0.16 billion m 3 After that, the total water supply capacity of Zunyi City's surface water source project is 2.47 billion m 3 .

[0132] Table 2 Statistics of water supply capacity of surface water source projects in Zunyi City in 2021

[0133]

[0134] By setting the water supply capacity adjustment coefficient of the surface water source project in the karst mountain area, as shown in Table 1, considering the impact of the karst mountain topography on the water supply capacity of the surface water source project, the water supply capacity of the water storage project in Zunyi City is 1.42 billion m 3 The water supply capacity of the diversion and lifting project is 739 million m 3 , further deducting the repeated calculation of the water supply capacity of surface water source projects by 16 million m 3 After that, the total water supply capacity of Zunyi City's surface water source projects was 2.143 billion m 3 .

[0135] The annual water consumption in Zunyi in 2021 is 2.386 billion m 3 The water supply capacity of Zunyi's underground water source project in 2021 is 12.8 million m 3 The water supply capacity of unconventional water sources is 25 million m 3 There is no over-exploitation of groundwater at present; the construction of the reservoir in the last century did not take into account the ecological flow discharge facilities, and after review, 0.65 billion m3 of ecological water in the river was occupied. 3 If the impact of karst mountain topography on the water supply capacity of surface water source projects is not taken into account, the water supply capacity of surface water source projects in Zunyi City is 2.47 billion m 3 The regional water supply capacity is 2.443 billion m 3 , the water supply safety factor is 1.02. According to the constructed water supply safety factor evaluation standard, the safety evaluation result of the water supply safety factor of Zunyi City is a low-level basic safety. According to the method proposed by the present invention, after considering the influence of the karst mountain topography on the water supply capacity of the surface water source project, the water supply capacity of the surface water source project in Zunyi City is calculated to be 2.143 billion m 3 The regional water supply capacity is 2.115 billion m 3 The water supply safety factor is 0.89. According to the constructed water supply safety factor evaluation standard, the safety evaluation result of Zunyi City’s water supply safety factor is unsafe, which is more in line with the actual situation and characteristics of water supply infrastructure and water supply safety conditions in karst mountainous areas.

[0136] In summary, the water supply safety factor evaluation method proposed in the present invention introduces a water supply safety factor to improve the adaptability and resilience of the water supply infrastructure system; by calculating the water supply safety factor and conducting a safety evaluation of the regional water supply system, it provides new practical technical means for understanding the current status of urban and rural water supply safety and discovering existing weak links, and planning the overall scale design of new water supply infrastructure; at the same time, according to the characteristics of the karst mountainous area, the water supply capacity of the surface water source project is analyzed to improve the accuracy of the water supply safety analysis in the karst mountainous area. Therefore, the present invention has good operability and replicability, and realizes a more objective evaluation of the water supply safety status of the study area, which can be used for the water supply capacity and supply and demand balance analysis of the study area in water resources allocation.

[0137] The present invention uses specific embodiments to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

[0138] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A method for evaluating water supply safety factor, characterized in that: The following steps are involved: S1. Determine the research area and evaluation level year for water supply safety factor evaluation, and obtain the evaluation data of the research area in the evaluation level year; Wherein, step S1 specifically includes: Determine the research area and evaluation level year for water supply safety factor evaluation, where the evaluation level year includes the current level year and the planned level year, specifically: If the evaluation level year is the current level year, the evaluation data of the current level year including the development and utilization of water resources, water supply infrastructure and river and lake ecosystem conditions shall be obtained; Among them, the development and utilization of water resources include the annual water consumption and water supply structure of the study area; The water supply infrastructure includes the number, scale, location and designed annual water supply capacity of surface water source projects, groundwater source projects and unconventional water sources in the study area. Surface water source projects include water storage projects and water diversion and lifting projects. Water diversion and lifting projects include water diversion projects, water lifting projects and water diversion projects. Among them, the status of river and lake ecosystems includes the amount of ecological water use squeezed out of rivers and groundwater overexploitation in the study area; If the evaluation level year is the planning level year, the evaluation data for the planning level year shall include the development and utilization of water resources, water supply infrastructure, and river and lake ecosystem conditions, as well as the target requirements for total water use control, groundwater over-exploitation management, limited and reduced extraction, and river and lake ecological flow protection, as well as evaluation data on water demand forecast results; S2. Based on the evaluation data of the study area in the evaluation level year obtained in step S1, determine whether there is a hydraulic connection between the surface water source projects in the study area. If there is a hydraulic connection, calculate the repeated calculation amount of the water supply capacity of the surface water source projects in the study area; Wherein, step S2 specifically includes: S21, according to the evaluation data of the surface water source projects in the evaluation data of the study area in the evaluation level year obtained in step S1, obtain the spatial relationship between the surface water source projects, and judge whether there is a hydraulic connection between the surface water source projects, such as upstream and downstream, and inflow and outflow. If so, execute step S22, otherwise, execute step S23; Among them, hydraulic connection refers to the relationship between water supply and discharge between surface water source projects; S22. Calculate the repeated calculation of the water supply capacity of the surface water source projects in the study area, that is: Among them, D s represents the repeated calculation of the water supply capacity of the surface water source project in the study area, o represents the number of locations where the surface water source project has hydraulic connection in the study area, and D sk It represents the repeated calculation of the water supply capacity of the surface water source project with hydraulic connection at the kth position in the study area under the average water inflow over many years; S23. The repeated calculation of water supply capacity of surface water source projects in the study area is 0; S3, calculating the water supply capacity of the surface water source project in the study area according to the repeated calculation amount of the water supply capacity of the surface water source project in the study area calculated in step S2 and the evaluation data of the study area in the evaluation level year obtained in step S1; S4, calculating the effective water supply capacity of the study area according to the evaluation data of the study area in the evaluation level year obtained in step S1 and the water supply capacity of the surface water source project in the study area calculated in step S3; S5. Calculate the water supply safety factor of the study area in the evaluation level year according to the annual water consumption of the study area and the effective water supply capacity of the study area calculated in step S4; S6. Construct a safety evaluation standard for water supply safety factor, and determine the safety level of the water supply safety factor of the study area calculated in step S5 in the evaluation level year.

2. The water supply safety factor evaluation method according to claim 1, characterized in that: Step S3 specifically includes: According to the repeated calculation of the water supply capacity of the surface water source project in the study area calculated in step S2 and the scale of the water storage project and the water diversion and water transfer project in the evaluation data of the study area in the evaluation level year obtained in step S1, the water supply capacity adjustment coefficient is set to calculate the water supply capacity of the surface water source project in the study area, that is: Among them, C s represents the water supply capacity of the surface water source project in the study area under the average water inflow over many years, m represents the number of scale levels of the water storage project, C ri represents the water supply capacity of the water storage project of scale i in the study area under the average water inflow over many years, α ri represents the water supply capacity adjustment coefficient of the water storage project with scale i in the study area, n represents the number of scale levels of water diversion and lifting projects, C dj represents the water supply capacity of the water diversion project of scale J in the study area under the average water inflow over many years, β dj It represents the water supply capacity adjustment coefficient of the water diversion project with a scale of j in the study area.

3. The water supply safety factor evaluation method according to claim 2, characterized in that: The specific process of setting the water supply capacity adjustment coefficient is: The larger the scale of the surface water source project, the smaller the impact of the topography of the study area on the water supply capacity of the surface water source project, and the larger the water supply capacity adjustment coefficient of the surface water source project is set. When the topography of the study area has no impact on the water supply capacity of the surface water source project, the water supply adjustment coefficient is set to 1.

4. The water supply safety factor evaluation method according to claim 2, characterized in that: Step S4 specifically includes: According to the water supply capacity of groundwater source projects, water supply capacity of unconventional water sources, groundwater overexploitation, ecological water use in rivers in the evaluation data of the study area in the evaluation level year obtained in step S1, and the water supply capacity of surface water source projects in the study area calculated in step S3, the effective water supply capacity of the study area is calculated, that is: C w =C s +C g +C n -W go -W eo Among them, c w represents the effective water supply capacity of the study area, C g Indicates the water supply capacity of the groundwater source project, C n Indicates the water supply capacity of unconventional water sources, W go represents the amount of groundwater overdraft, W eo Indicates the amount of ecological water usage in the river.

5. The water supply safety factor evaluation method according to claim 4, characterized in that: Step S5 specifically includes: According to the annual water consumption of the study area and the effective water supply capacity of the study area calculated in step S4, the water supply safety factor of the study area in the evaluation level year is calculated, that is: Among them, P represents the water supply safety factor of the study area in the evaluation level year, W u represents the annual water consumption in the study area.

6. The water supply safety factor evaluation method according to claim 5, characterized in that: The annual water consumption in the study area is: If the evaluation level year is the current level year, the annual water consumption of the study area is the annual water consumption of the study area in the current level year; If the evaluation level year is the planning level year, the annual water consumption of the study area is calculated using the following formula: Among them, W d W represents the total water demand of the study area under the multi-year average water inflow in the planning level year. r It represents the total water consumption control index value of the study area in the planning level year.

7. The water supply safety factor evaluation method according to claim 5, characterized in that: Step S6 specifically includes: S61. Classify the water supply safety factor into safety levels and establish a water supply safety factor evaluation standard, specifically: When S ≥ 1.8, the water supply in the study area is safe; When 1.5≤S<1.8, the water supply in the study area is safe; When 1.0≤S<1.5, the water supply in the study area is basically safe; When 0.85≤S<1.0, the water supply in the study area is unsafe; When S < 0.85, the water supply in the study area is extremely unsafe; S62. According to the water supply safety factor evaluation standard constructed in step S61, determine the safety level of the water supply safety factor of the study area calculated in step S5 in the evaluation level year.

Images