Urban drought monitoring and early warning method based on water source topological structure

Abstract

The invention discloses an urban drought monitoring and early warning method based on a water source topological structure. The method comprises the steps that the urban water supply source topological structure is constructed, the water supply amount of an urban water supply plant in the drought period is calculated, the water demand amount of water using objects in urban water supply areas in the drought period is calculated, and the urban drought monitoring and early warning level is determined. According to the method, the water supply and demand is finely calculated by constructing the water source topological association, so that the partitioned accurate early warning is realized, and the accuracy and practicability of urban drought monitoring and early warning are remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of urban water resource management and drought prevention and mitigation technology, and specifically relates to an urban drought monitoring and early warning method based on water source topology. Background Technology

[0002] With the intensification of global climate change, the increasing frequency and intensity of droughts pose a serious threat to the stability of urban water supply systems. Cities, as densely populated and industrially concentrated core areas, have diverse water demands encompassing residential life, industrial production, public services, and ecological environment maintenance, making them highly dependent on water resources. Drought not only directly impacts the safety of daily drinking water for residents but can also lead to industrial shutdowns, ecological degradation, and consequently trigger a chain reaction of economic losses and social risks. Therefore, establishing a precise and efficient urban drought monitoring and early warning system has become a core requirement for ensuring urban water security.

[0003] However, existing urban drought monitoring and early warning methods have significant technical limitations and are difficult to adapt to the actual needs of complex urban water supply systems:

[0004] ① Ignoring the hydraulic connections between water sources leads to one-sided water supply calculations: Traditional methods often use the overall urban water supply as the sole criterion for judgment, failing to consider the complex topological relationships of urban water sources—such as the water supply links between different water sources like reservoirs, river intakes, and groundwater wells and water plants; the regulatory role of water conservancy facilities like sluice gates and pumping stations in water delivery; and the precise matching relationship between water plants and different water supply areas and water users. This fragmented calculation makes it impossible to accurately assess the actual water supply capacity of each water source during drought periods, easily leading to deviations in water supply forecasts and thus affecting the accuracy of early warnings.

[0005] ② The calculation of water demand is crude and lacks classification adaptability: Existing technologies do not subdivide the differentiated demand characteristics of different water users in the city (such as domestic water use, industrial water use, public water use, and ecological water use). They only use a uniform water use index to estimate water demand during drought periods, and do not introduce drought correction coefficients to adapt to changes in water use behavior under drought conditions (such as residential water conservation and industrial production restrictions). This "one-size-fits-all" method of calculating water demand makes it difficult to reflect the real demand of different areas and different types of water use, resulting in a distortion of supply and demand balance analysis.

[0006] ③ The early warning level is determined in a single way, lacking spatial precision: Traditional early warning systems often determine drought levels based on the city as a whole, without considering the differences in water source security and water demand characteristics of different water supply areas to create zoned early warnings. When local areas of the city (such as areas relying on a single river source) experience water shortages, the overall early warning system cannot identify local risks in a timely manner, which can delay the implementation of targeted emergency response measures and reduce the city's ability to manage drought in a refined manner.

[0007] In summary, existing urban drought monitoring and early warning methods suffer from insufficient accuracy due to neglecting water source topological relationships, inaccurate water demand classification, and lack of spatial segmentation in early warning. This makes it difficult to effectively support the precise prevention and control of urban drought disasters. There is an urgent need for a technical solution that can integrate the entire water source chain relationship, segment water demand types, and achieve precise regional early warning to address the aforementioned technical pain points. Summary of the Invention

[0008] To overcome the problems of existing technologies, this invention proposes an urban drought monitoring and early warning method based on water source topology. This method combines urban water supply source topology with urban drought monitoring, which has the technical effect of improving the accuracy of urban drought monitoring and early warning.

[0009] The objective of this invention is achieved as follows:

[0010] This invention provides a method for urban drought monitoring and early warning based on water source topology, comprising the following steps:

[0011] Step 1: Construct the urban water supply source topology

[0012] S11, Obtain basic data of various water supply-related elements: the various water supply-related elements include reservoirs, river intakes, groundwater wells, river systems, water collection points, sluice gates, pumping stations, water plants, water supply areas, and water users;

[0013] S12, organize the basic data of the various water supply-related elements and establish a relational basic database table;

[0014] S13. Based on the aforementioned relational database tables, establish a relationship table between river systems and reservoirs, river intakes, sluice gates, and pumping stations by combining river system codes; establish a relationship table between reservoirs / river intakes / groundwater wells and water plants by combining reservoir / river intake / groundwater well codes; and establish a relationship table between water plants, water supply areas, and water users by combining water plant codes. Construct the urban water supply source topology through the above three types of relationship tables.

[0015] Step 2: Calculate the water supply capacity available to the city's water supply plants during the dry season.

[0016] Calculate the available water volume during the drought period for reservoir water, river water, and groundwater, respectively. Then, combine the urban water supply source topology structure constructed in step 1 to calculate the available water volume for urban water supply plants during the drought period.

[0017] Step 3: Calculate the daily water demand of water users in the urban water supply area during the dry season.

[0018] Obtain the unit water consumption quota, scale of water users and drought correction coefficient for different water users in the city, and calculate the daily water demand of water users in the urban water supply area during the drought period.

[0019] Step 4: Determine the urban drought monitoring and early warning level.

[0020] Based on the criteria for judging urban drought, the number of days of water supply guarantee in different water supply areas of the city is calculated. When the number of days of water supply guarantee is between 30 and 45 days, it is the drought emergency period; when the number of days of water supply guarantee is less than 30 days, it is the drought critical period, thereby determining the urban drought monitoring and early warning level.

[0021] Furthermore, in step 1, the basic data of the reservoir, river intake, and groundwater well includes name, code, latitude and longitude, administrative region, river, and characteristic parameters of different types of water supply sources; the basic data of the river system includes name, code, latitude and longitude, administrative region, and river level; the basic data of the water catchment point, sluice gate, pumping station, and water plant includes name, code, latitude and longitude, administrative region, and river; the basic data of the water supply area includes name, code, latitude and longitude, water supply plant, and water user category; the basic data of the water user includes name, area, unit water quota, population, industrial added value, building and tertiary industry added value, and green area.

[0022] Furthermore, the characteristic parameters of the different types of water supply sources include the total reservoir capacity, dead reservoir capacity, annual regulating reservoir capacity, maximum water supply capacity, water intake capacity of river intake projects, and exploitable groundwater well capacity.

[0023] Furthermore, in step 2, the formula for calculating the available water supply during the drought period of the reservoir is as follows:

[0024] W1 = S t +S t-1 -W r -L t

[0025] In the formula, W1 represents the water supply available from the reservoir during the dry season, and S... t S represents the inflow of water into the reservoir on a given day. t-1 W represents the water level stored in the reservoir the previous day. r For dead storage capacity or adjustable storage capacity, L t Evaporation and leakage loss on a certain day;

[0026] The formula for calculating the available water volume during the dry season of the river channel is as follows:

[0027] W2=(Z t ~Q t )×Δt-S r

[0028] In the formula, W2 represents the available water volume during the dry season in the river channel, and Z... t ~Q tThe current water intake level corresponds to the runoff volume, Δt is the water intake time, and S is the flow rate. r For the ecological baseline flow of the river;

[0029] The formula for calculating the available groundwater supply during the dry season is as follows:

[0030] W3=(S a -S b )μ k

[0031] In the formula, W3 represents the available groundwater supply during the dry season, and S... a S represents groundwater recharge. b Groundwater discharge, μ k This is the exploitability coefficient of groundwater;

[0032] The formula for calculating the water supply capacity of the urban water supply plant during the dry season is as follows:

[0033]

[0034] In the formula, W4 represents the amount of water that the urban water supply plant can provide during the dry season.

[0035] Furthermore, in step 3, the formula for calculating the daily water demand of the water users in the urban water supply area during the dry season includes:

[0036] Q1=(d1×R1) / 1000×α k1

[0037] Q2=(d2×R2) / 1000×α k2

[0038] Q3=(d3×R3) / 365×α k3

[0039] Q4=(d4×R4) / 365×α k4

[0040]

[0041] In the formula, Q1 to Q4 represent urban domestic water consumption, public water consumption, industrial water consumption, building water consumption, and tertiary industry water consumption, respectively; d1 to d4 represent urban domestic water consumption, public water consumption, industrial water consumption, building water consumption, and tertiary industry water consumption quotas, respectively; R1 to R4 represent urban resident population, green space area, industrial added value, and building and tertiary industry added value, respectively; and α represents urban resident population, green space area, industrial added value, and building and tertiary industry added value, respectively. k1 ~α k4 These are drought correction coefficients for different water users, and Q5 represents the daily water demand of water users in the urban water supply area during the drought period.

[0042] Furthermore, in step 4, the formula for calculating the number of days of guaranteed water supply in different water supply areas of the city is as follows:

[0043] D ys =W4 / Q5

[0044] In the formula, D ys W4 represents the number of days that the urban water supply area can guarantee water supply, W5 represents the amount of water that the urban water supply plant can supply during the dry season, and Q5 represents the daily water demand of the water users in the urban water supply area during the dry season.

[0045] The urban drought monitoring and early warning method based on water source topology provided by this invention significantly improves the accuracy and practicality of urban drought monitoring and early warning by constructing water source topological associations, refining the calculation of urban water supply and demand during drought periods, and achieving precise regional early warning. Specific beneficial effects are as follows:

[0046] 1. Constructing a complete water source topology for accurate water supply capacity assessment: This invention, for the first time, integrates all elements of the urban water supply system, including reservoirs, river intakes, groundwater wells, river systems, sluices, pumping stations, water plants, water supply areas, and water users, into a complete urban water supply source topology structure by establishing a relational database and related tables. This structure clearly reflects the hydraulic relationships and control logic between each water source and water plant, water plant and water supply area, and water supply area and water users. Combined with differentiated water supply calculation models for reservoirs, rivers, and groundwater (e.g., considering dead / regulating reservoir capacity, river ecological base flow, and groundwater exploitability coefficient), it can accurately quantify the actual water supply capacity of each water plant and area during drought periods. This solves the technical pain point of the traditional "fragmented" water supply assessment method and provides accurate water supply data support for early warning.

[0047] 2. Subdividing Water Demand Types and Adjustment Coefficients for Precise Matching of Actual Needs: This invention sets unit water quotas and water scale parameters for different water users, including urban residents, industry, public facilities, and ecological users, and introduces drought adjustment coefficients to adapt to changes in water use behavior under drought conditions. By calculating the drought-period water demand of each water user group and then summing the results to obtain the total water demand of each water supply area, it achieves "categorized and differentiated" calculation of water demand, avoiding the bias of the "extensive" water demand estimation in traditional methods. This makes the supply and demand balance analysis more closely aligned with the real needs of different areas and water use types in the city, providing accurate water demand data for subsequent early warning level determination.

[0048] 3. Achieving precise regional early warning and improving the targeting of emergency dispatch: Based on the calculation results of regional water supply and demand under the water source topology, this invention introduces "number of days of guaranteed water supply" as the core early warning indicator, and combines it with urban drought discrimination standards (30-45 days is the emergency period of drought, less than 30 days is the critical period of drought) to independently determine the early warning level of each water supply area. This "regional" early warning can accurately identify the differences in drought risk in different areas within the city (e.g., the early warning level may be different for areas relying on reservoir water sources and areas relying on groundwater sources), enabling city managers to formulate targeted emergency measures for high-risk areas (e.g., cross-regional water transfer, local water conservation control), avoiding the limitations of traditional "holistic" early warning that cannot identify local risks, and significantly improving the refined management capabilities and emergency dispatch efficiency of urban drought response.

[0049] 4. Supporting long-term urban water security management with broad application value: The water source topology database and supply-demand calculation model constructed in this invention can not only be used for monitoring and early warning during drought periods, but also serve as a basic tool for daily urban water resource management—for example, for optimizing routine water source scheduling, assessing water use efficiency, and improving the resilience of water supply systems. Its technical solution is adaptable to cities of different sizes and with different water source structures (such as cities primarily reliant on reservoirs or cities with mixed water supply from multiple sources), exhibiting strong versatility and scalability. It can provide long-term technical support for urban water resource security and drought disaster prevention, with broad application prospects. Attached Figure Description

[0050] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0051] Figure 1 This is a flowchart illustrating the urban drought monitoring and early warning method based on water source topology as described in an embodiment of the present invention;

[0052] Figure 2 The constructed urban water source topology of Fujian Province is shown.

[0053] Figure 3 This paper presents the constructed urban drought monitoring and early warning system for Fujian Province based on water source topology. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments disclosed herein will be described in further detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0055] Example 1:

[0056] like Figure 1As shown in the figure, this embodiment provides a method for urban drought monitoring and early warning based on water source topology, including the following steps:

[0057] Step 1: Construct the urban water supply source topology

[0058] S11, Obtain basic data on various water supply-related elements: These elements include reservoirs, river intakes, groundwater wells, river systems, water catchment points, sluice gates, pumping stations, water plants, water supply areas, and water users; the basic data for reservoirs, river intakes, and groundwater wells includes their names, codes, latitude and longitude, administrative regions, rivers, and characteristic parameters of different types of water sources (including total reservoir capacity, dead storage capacity, annual regulating capacity, and maximum water supply capacity; water intake capacity of river intake projects; and exploitable groundwater wells). The basic data of the river system includes name, code, latitude and longitude, administrative region and river level; the basic data of the water catchment point, sluice gate, pumping station and water plant includes name, code, latitude and longitude, administrative region and river; the basic data of the water supply area includes name, code, latitude and longitude, water supply plant and water user category; the basic data of the water user includes name, area, unit water quota, population, industrial added value, building and tertiary industry added value and green area.

[0059] S12, organize the basic data of the various water supply-related elements and establish a relational basic database table.

[0060] S13. Based on the aforementioned relational database tables, establish a relationship table between river systems and reservoirs, river intakes, sluice gates, and pumping stations by combining river system codes; establish a relationship table between reservoirs / river intakes / groundwater wells and water plants by combining reservoir / river intake / groundwater well codes; and establish a relationship table between water plants, water supply areas, and water users by combining water plant codes. Construct the urban water supply source topology through the above three types of relationship tables.

[0061] Step 2: Calculate the water supply capacity available to the city's water supply plants during the dry season.

[0062] Calculate the available water volume during the drought period for reservoir water, river water, and groundwater, respectively. Then, combine the urban water supply source topology structure constructed in step 1 to calculate the available water volume for urban water supply plants during the drought period.

[0063] The formula for calculating the available water supply from the reservoir during the drought period is as follows:

[0064] W1 = S t +S t-1 -W r -L t

[0065] In the formula, W1 represents the water supply available from the reservoir during the dry season, and S... t S represents the inflow of water into the reservoir on a given day. t-1 W represents the water level stored in the reservoir the previous day. r For dead storage capacity or adjustable storage capacity, L t Evaporation and leakage loss on a certain day;

[0066] The formula for calculating the available water volume during the dry season of the river channel is as follows:

[0067] W2=(Z t ~Q t )×Δt-S r

[0068] In the formula, W2 represents the available water volume during the dry season in the river channel, and Z... t ~Q t The current water intake level corresponds to the runoff volume, Δt is the water intake time, and S is the flow rate. r For the ecological baseline flow of the river;

[0069] The formula for calculating the available groundwater supply during the dry season is as follows:

[0070] W3=(S a -S b )μ k

[0071] In the formula, W3 represents the available groundwater supply during the dry season, and S... a S represents groundwater recharge. b Groundwater discharge, μ k This is the exploitability coefficient of groundwater;

[0072] The formula for calculating the water supply capacity of the urban water supply plant during the dry season is as follows:

[0073]

[0074] In the formula, W4 represents the amount of water that the urban water supply plant can provide during the dry season.

[0075] Step 3: Calculate the daily water demand of water users in the urban water supply area during the dry season.

[0076] To obtain the unit water consumption quota, scale of different water users in the city, and drought correction coefficient, the daily water demand of water users in the urban water supply area during the drought period is calculated. The calculation formula includes:

[0077] Q1=(d1×R1) / 1000×α k1

[0078] Q2=(d2×R2) / 1000×α k2

[0079] Q3=(d3×R3) / 365×α k3

[0080] Q4=(d4×R4) / 365×α k4

[0081]

[0082] In the formula, Q1 to Q4 represent urban domestic water consumption, public water consumption, industrial water consumption, building water consumption, and tertiary industry water consumption, respectively; d1 to d4 represent urban domestic water consumption, public water consumption, industrial water consumption, building water consumption, and tertiary industry water consumption quotas, respectively; R1 to R4 represent urban resident population, green space area, industrial added value, and building and industrial added value, respectively; α k1 ~α k4 These are drought correction coefficients for different water users, and Q5 represents the daily water demand of water users in the urban water supply area during the drought period. The drought correction coefficients and quotas for non-water users are determined based on historical urban water use data.

[0083] Step 4: Determine the urban drought monitoring and early warning level.

[0084] Based on the criteria for identifying urban drought, the number of days of guaranteed water supply in different water supply areas of the city is calculated using the following formula:

[0085] D ys =W4 / Q5

[0086] In the formula, D ys The number of days that the city's water supply area can guarantee water availability.

[0087] When the number of days with guaranteed water supply is between 30 and 45 days, it is considered an emergency period of drought (severe drought); when the number of days with guaranteed water supply is less than 30 days, it is considered a critical period of drought (extreme drought), thus determining the urban drought monitoring and early warning level.

[0088] Application examples:

[0089] Taking Fujian Province as an example, the method described in Example 1 was used to construct the urban water source topology of Fujian Province, such as... Figure 2 As shown, the map intuitively displays the relationships between reservoirs, river intakes, groundwater wells, and water plants, as well as the relationships between water plants and urban water supply areas, and enables interaction with the map. Based on this, using the method described in Example 1, the drought-period water supply capacity of urban water plants in various prefecture-level cities of Fujian Province and the daily drought-period water demand of water users in urban water supply areas were calculated, and the drought warning level for cities in Fujian Province was determined. The results are as follows: Figure 3 As shown, this method can be used for urban drought monitoring and early warning.

[0090] Finally, it should be noted that the above is only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention (such as the application of various formulas, the order of steps, etc.) without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for urban drought monitoring and early warning based on water source topology, characterized in that, The method includes the following steps: Step 1: Construct the urban water supply source topology S11, Obtain basic data of various water supply-related elements: the various water supply-related elements include reservoirs, river intakes, groundwater wells, river systems, water collection points, sluice gates, pumping stations, water plants, water supply areas, and water users; S12, organize the basic data of the various water supply-related elements and establish a relational basic database table; S13. Based on the aforementioned relational database tables, establish a relationship table between river systems and reservoirs, river intakes, sluice gates, and pumping stations by combining river system codes; establish a relationship table between reservoirs / river intakes / groundwater wells and water plants by combining reservoir / river intake / groundwater well codes; and establish a relationship table between water plants, water supply areas, and water users by combining water plant codes. Construct the urban water supply source topology through the above three types of relationship tables. Step 2: Calculate the water supply capacity available to the city's water supply plants during the dry season. Calculate the available water volume during the drought period for reservoir water, river water, and groundwater, respectively. Then, combine the urban water supply source topology structure constructed in step 1 to calculate the available water volume for urban water supply plants during the drought period. Step 3: Calculate the daily water demand of water users in the urban water supply area during the dry season. Obtain the unit water consumption quota, scale of water users and drought correction coefficient for different water users in the city, and calculate the daily water demand of water users in the urban water supply area during the drought period. Step 4: Determine the urban drought monitoring and early warning level. Based on the criteria for judging urban drought, the number of days of water supply guarantee in different water supply areas of the city is calculated. When the number of days of water supply guarantee is between 30 and 45 days, it is the drought emergency period; when the number of days of water supply guarantee is less than 30 days, it is the drought critical period, thereby determining the urban drought monitoring and early warning level.

2. The urban drought monitoring and early warning method based on water source topology according to claim 1, characterized in that, In step 1, the basic data of the reservoir, river intake, and groundwater well includes name, code, latitude and longitude, administrative region, river, and characteristic parameters of different types of water supply sources; the basic data of the river system includes name, code, latitude and longitude, administrative region, and river level; the basic data of the water catchment point, sluice gate, pumping station, and water plant includes name, code, latitude and longitude, administrative region, and river; the basic data of the water supply area includes name, code, latitude and longitude, water supply plant, and water user category; the basic data of the water user includes name, area, unit water quota, population, industrial added value, building and tertiary industry added value, and green area.

3. The urban drought monitoring and early warning method based on water source topology according to claim 2, characterized in that, The characteristic parameters of different types of water supply sources include the total reservoir capacity, dead storage capacity, annual regulating capacity, and maximum water supply capacity of reservoirs, the water intake capacity of river intake projects, and the exploitable amount and water intake capacity of groundwater wells.

4. The urban drought monitoring and early warning method based on water source topology according to claim 1, characterized in that, In step 2, the formula for calculating the available water supply during the drought period of the reservoir is as follows: W1=S t +S t-1 -W r -L t In the formula, W1 represents the water supply available from the reservoir during the dry season, and S... t S represents the inflow of water into the reservoir on a given day. t-1 W represents the water level stored in the reservoir the previous day. r For dead storage capacity or adjustable storage capacity, L t Evaporation and leakage loss on a certain day; The formula for calculating the available water volume during the dry season of the river channel is as follows: W2=(Z t ~Q t )×Δt-S r In the formula, W2 represents the available water volume during the dry season in the river channel, and Z... t ~Q t The current water intake level corresponds to the runoff volume, Δt is the water intake time, and S is the flow rate. r For the ecological baseline flow of the river; The formula for calculating the available groundwater supply during the dry season is as follows: W3=(S a -S b )μ k In the formula, W3 represents the available groundwater supply during the dry season, and S... a S represents groundwater recharge. b Groundwater discharge, μ k This is the exploitability coefficient of groundwater; The formula for calculating the water supply capacity of the urban water supply plant during the dry season is as follows: In the formula, W4 represents the amount of water that the urban water supply plant can provide during the dry season.

5. The urban drought monitoring and early warning method based on water source topology according to claim 1, characterized in that, In step 3, the formula for calculating the daily water demand of water users in the urban water supply area during the dry season is as follows: include: Q1=(d1×R1) / 1000×α k1 Q2=(d2×R2) / 1000×α k2 Q3=(d3×R3) / 365×α k3 Q4=(d4×R4) / 365×α k4 In the formula, Q1 to Q4 represent urban domestic water consumption, public water consumption, industrial water consumption, building water consumption, and tertiary industry water consumption, respectively; d1 to d4 represent urban domestic water consumption, public water consumption, industrial water consumption, building water consumption, and tertiary industry water consumption quotas, respectively; R1 to R4 represent urban resident population, green space area, industrial added value, and building and industrial added value, respectively; α k1 ~α k4 These are drought correction coefficients for different water users, and Q5 represents the daily water demand of water users in the urban water supply area during the drought period.

6. The urban drought monitoring and early warning method based on water source topology according to claim 1, characterized in that, In step 4, the formula for calculating the number of days of guaranteed water supply in different water supply areas of the city is as follows: D ys =W4 / Q5 In the formula, D ys W4 represents the number of days that the urban water supply area can guarantee water supply, W5 represents the amount of water that the urban water supply plant can supply during the dry season, and Q5 represents the daily water demand of the water users in the urban water supply area during the dry season.

Images