Urban underground water level monitoring equipment and urban underground water level monitoring and early warning method

Abstract

The invention provides urban underground water level monitoring equipment and an urban underground water level monitoring early warning method.The monitoring equipment comprises a filter pipe, the bottom end of the filter pipe is inserted into the ground of a to-be-detected area, the top end of the filter pipe extends out of the ground of the to-be-detected area, a hole is formed in the part, extending into the ground, of the filter pipe, and the part, located in the hole, of the filter pipe is coated with geotechnical cloth; the buoy extends into the filter pipe from the top end of the filter pipe, and the top of the buoy is provided with an indicator; the transparent pipe is mounted at the top end of the filter pipe through a sleeve, the lower half part of the sleeve is arranged at the top end of the filter pipe in a sleeving manner, and the upper half part of the sleeve is arranged at the bottom end of the transparent pipe in a sleeving manner; the ruler is installed on the inner wall of the transparent tube, scale marks are arranged on the ruler, and the top end of the indicator corresponds to the scale marks.

Description

Technical Field

[0001] This application relates to the field of groundwater level monitoring technology, and in particular to an urban groundwater level monitoring device and an urban groundwater level monitoring and early warning method. Background Technology

[0002] In the field of urban groundwater level monitoring, traditional methods mainly rely on electronic sensors or manual measuring equipment. Electronic sensors (such as pressure level gauges or ultrasonic rangefinders) require continuous power supply, data transmission systems, and regular calibration, resulting in high costs, susceptibility to environmental influences, and a high failure rate, especially with heavy maintenance burdens during long-term monitoring. Manual measurement methods often use measuring ropes or electronic inductive rangefinders, requiring the opening of the monitoring well's sealing device. The measurement process requires multiple people to work together, and the operation is cumbersome (such as wiping the probe and restoring the seal), which is not only inefficient but may also damage the sealing of the monitoring point, affecting data accuracy. In addition, existing equipment is often structurally complex and difficult to adapt to the installation requirements of different geographical conditions, such as in densely populated urban areas or remote suburbs, where equipment transportation and adjustment are difficult. Summary of the Invention

[0003] The purpose of this invention is to solve the above-mentioned problems by providing an urban groundwater level monitoring device and an urban groundwater level monitoring and early warning method.

[0004] The technical solution of this application is implemented as follows: In a first aspect, this application provides an urban groundwater level monitoring device, the monitoring device comprising: The filter tube is inserted into the ground of the area to be tested at its bottom end and extends out of the ground of the area to be tested at its top end. The part of the filter tube that extends into the ground has holes, and the part of the filter tube with holes is covered with geotextile. A buoy extends into the filter tube from the top of the filter tube, and the top of the buoy has an indicator beacon; A transparent tube is installed at the top of the filter tube via a sleeve, with the lower half of the sleeve fitted over the top of the filter tube and the upper half fitted over the bottom of the transparent tube. A scale is installed on the inner wall of a transparent tube, and the scale has graduation marks, with the top of the indicator corresponding to the graduation marks.

[0005] The advantages or beneficial effects of the above technical solutions include at least the following: Secondly, this application also provides a groundwater level monitoring device and the monitoring method thereof, which includes: Groundwater level monitoring equipment is distributed and installed in the areas to be monitored, and a dynamic threshold for warning water level is established based on the seasonal characteristics and historical hydrological patterns of the area; when the monitored water level reaches or exceeds the dynamic threshold, a graded warning is activated.

[0006] The process of establishing a dynamic threshold for early warning water levels based on historical hydrological patterns and seasonal characteristics of the region includes the following steps: S1. Obtaining Seasonal Baseline Thresholds: Obtain the highest and lowest safe groundwater levels for the region; group by season and obtain the 90% confidence interval for the average water level under different seasons to obtain the water level fluctuation boundary in the normal season; introduce a safety redundancy coefficient α to determine the upper limit threshold H of the seasonal baseline. base，S，UP and seasonal baseline lower limit threshold H base，S，low ; S2. Perform functional zone correction: Divide the urban area into multiple functional zones according to water level risk sensitivity, and set an upper limit correction coefficient K for each functional zone. func,up and lower limit correction factor K func,low Through the seasonal benchmark upper limit threshold H base,S,up Correction coefficient K for the upper limit of the corresponding functional area func,up The upper limit threshold H after functional correction is calculated. func,up The seasonal baseline lower limit threshold H base,S,low The lower limit correction coefficient K of the corresponding functional area func,low The lower limit threshold H after functional correction is calculated. func,low ; S3. Under normal operating conditions, the upper limit threshold H after the function is corrected. func,up And the lower limit threshold H after functional correction func,low As the final dynamic early warning threshold; under extreme operating conditions, an extreme operating condition correction coefficient K is introduced. extreme , respectively with the functionally corrected upper limit threshold H func,up And the lower limit threshold H after functional correction func,low Multiplying these values ​​yields the final dynamic warning threshold under extreme conditions, which is the final upper limit threshold H. func,up and the final lower limit threshold H func,low ; The groundwater level monitoring equipment is the same as described in claim 1 or 2.

[0007] The advantages or beneficial effects of the above technical solutions include at least the following: The monitoring equipment and intelligent early warning methods, combined organically, constitute a highly efficient, reliable, and intelligent urban groundwater level monitoring and early warning system, bringing significant benefits: The monitoring equipment employs a purely mechanical structure (filter tube, buoy, and telescopic standard rod), requiring no power supply or complex electronic components, offering advantages such as low cost, durability, and simple maintenance. Its unique sealed design (transparent tube and sleeve connection) ensures the stability of the monitoring environment, while the intuitive scale reading method lowers the operational threshold, allowing for measurements to be completed by a single person, greatly improving efficiency. This equipment provides a stable and reliable data source for subsequent accurate early warning systems.

[0008] The monitoring method breaks through the limitations of the traditional fixed threshold model. By introducing seasonal benchmarks, functional zone corrections, and extreme condition coefficients, a dynamically adjustable early warning threshold is established. This makes the early warning signals more scientific and accurate, effectively reducing false alarms and missed alarms. Combined with the blue, yellow, orange, and red tiered early warning mechanism, it can trigger tiered response measures from "attention" to "city-level emergency response," achieving optimized allocation of emergency resources and proactive risk management. Reliable, low-cost equipment makes it possible to densely deploy monitoring points over large areas, providing a massive, real-time data foundation for early warning methods. Advanced early warning methods, on the other hand, fully leverage the value of the data collected by the equipment, transforming simple water level readings into decision-making information with guiding significance. The combination of these two approaches achieves a leap from "passive monitoring" to "proactive early warning," making it particularly suitable for the management of modern cities with complex terrain and functions.

[0009] The equipment itself is flexibly adjustable (e.g., the standard pole can be detached and extended) to adapt to different monitoring depths and can be simplified for use in non-sealed scenarios, making it highly versatile. The early warning method uses an extreme condition correction coefficient to enable the system to temporarily activate stricter thresholds under abnormal conditions such as heavy rain and drought, demonstrating good adaptability and anti-interference capabilities, and ensuring the safety of the city under extreme weather conditions. Attached Figure Description

[0010] The accompanying drawings illustrate exemplary embodiments of the present application and, together with the description thereof, serve to explain the principles of the present application. These drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of this specification.

[0011] Figure 1 A schematic diagram of the monitoring device of this invention installed underground is shown in an embodiment of the invention; Figure 2 A schematic diagram of the standard rod and connector according to an embodiment of the present invention is shown; Reference numerals: 10, filter tube; 20, buoy; 21, indicator; 211, standard rod; 2111, external thread section; 212, iron plate; 213, nut; 214, indicator head; 30, transparent tube; 31, scale; 40, sleeve. Detailed Implementation

[0012] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While some embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this application. It should be understood that the drawings and embodiments of this application are for illustrative purposes only and are not intended to limit the scope of protection of this application.

[0013] It should be noted that, where there is no conflict, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0014] It should be understood that the term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc., mentioned in this application are used only to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0015] It should be noted that the terms "one" and "more" used in this application are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0016] The names of the messages or information exchanged between multiple devices in the embodiments of this application are for illustrative purposes only and are not intended to limit the scope of these messages or information.

[0017] Reference Figure 1 A city groundwater level monitoring device, the monitoring device comprising: The filter tube 10 is inserted into the ground of the area to be tested at its bottom end and extends out of the ground of the area to be tested at its top end. The part of the filter tube 10 that extends into the ground has holes. The part of the filter tube 10 with holes is covered with geotextile. The geotextile can prevent sand and gravel from entering the filter tube 10 through the holes. A buoy 20 extends into the filter tube 10 from its top end, and has an indicator 21 at its top. The indicator 21 includes a standard rod 211 and a connector. The standard rods 211 are detachably connected to each other via the connector, with the bottommost standard rod 211 fixedly connected to the buoy 20. The connector includes iron plates 212 and nuts 213. The iron plates 212 are arranged in pairs, and there are two nuts 213 welded to the inner sides of the upper and lower ends of the two iron plates 212. The end of the standard rod 211 has an external thread section 2111 that matches the nut 213, allowing the entire indicator 21 to extend or retract in the height direction for easy installation and disassembly. Furthermore, an indicator head is installed at the top of the uppermost standard rod, corresponding to the scale markings for easy observation of the degree readings by the user.

[0018] The transparent tube 30 is installed at the top of the filter tube 10 through the sleeve 40. The lower half of the sleeve is fitted onto the top of the filter tube 10, and the upper half is fitted onto the bottom of the transparent tube 30. A scale 31 is installed on the inner wall of the transparent tube 30. The scale 31 has graduation marks, and the top of the indicator 21 corresponds to the graduation marks.

[0019] The specific installation steps for the aforementioned urban groundwater level monitoring equipment are as follows: 1. Installation of PVC filter pipe 10: Use a 110mm diameter drilling machine to drill a hole in the ground until the designed groundwater level depth is reached. Select a 70mm PVC filter pipe 10, make holes in the side wall of the filter pipe 10, wrap it with geotextile, and then insert it into the drilled hole. Fill the holes in the filter pipe 10 with fine sand and then seal them. Ensure that the upper end of the PVC filter pipe 10 protrudes at least 200mm above the ground. After the buoy 20 and standard rod 211 are installed, install the transparent tube 30. First, ensure that the inside of the filter pipe 10 is clean, and ensure that it is vertical during installation to ensure that the buoy 20 can move up and down with the water level.

[0020] 2. Installation of Plastic Buoy 20 and Galvanized Standard Rod 211: The plastic buoy 20 is made of 3mm thick HDPE hollow plastic with dimensions of ɸ50mm*1000mm, and its top is connected to the galvanized standard rod 211. The galvanized standard rod 211 is made of ɸ5 galvanized round steel, with threads at both ends, the thread length being approximately 50mm. The galvanized standard rods 211 are connected by a connector, which is made of two M5 nuts 213 welded to a 2mm thick iron sheet, with a 60mm distance between the outer ends of the two nuts 213. The length of the standard rod 211 screwed into the nuts 213 is not less than 25mm, and the ends are tightly connected without gaps to ensure that the length and size meet the requirements. At the top of the standard rod 211, a circular plastic plate indicator 21 is made of plastic sheet and firmly glued to the standard rod 211 for observing the reading at the top of the standard rod 211.

[0021] 3. Installation of the transparent plastic tube: The transparent plastic tube is made of 5mm thick plexiglass through heat processing, with a height of 1500mm and a diameter the same as the PVC filter tube 10. Its main function is to maintain the sealing performance and allow direct observation of the reading of the indicator 21 on the plastic plate at the top of the standard rod 211. The lower end of the transparent plastic tube is connected to the PVC filter tube 10 using an ɸ65 PVC sleeve 40, which is then tightly wrapped with rubber sealing material and secured with pipe clamps to ensure no air leakage.

[0022] 4. Fabrication and installation of aluminum ruler 31: Vertically fix the aluminum ruler 31 onto the transparent plastic tube. The ruler 31 is 1000mm long, and its bottom is aligned with the base of the transparent tube 30. The surface of the ruler 31 is decorated with red and black colors, each color being 10mm wide, achieving centimeter-level accuracy.

[0023] 5. Water Level Measurement Method: When the groundwater level changes, the plastic buoy 20 and the standard rod 211 sink synchronously, transmitting the change to the plastic plate indicator 21 at the top. The plastic plate indicator 21 reflects the water level drop on the scale 31. By calculating the correction length of the standard rod 211, plastic buoy 20, and standard rod 211 under their own weight, the relative height difference between the groundwater level and the plastic plate indicator 21 can be calculated. Then, when the surveyor reads the horizontal line of sight on the scale 31, by calculating the height difference between this reading and the plastic plate indicator 21, and combining it with the previously calculated value, the groundwater level elevation can be calculated, thus achieving the purpose of monitoring the groundwater level.

[0024] Embodiments of the present invention also provide a groundwater level monitoring method. The monitoring method includes: Groundwater level monitoring equipment is distributed and installed in the area to be monitored. A dynamic threshold for the warning water level is established based on the seasonal characteristics and historical hydrological patterns of the area. When the monitored water level reaches or exceeds the dynamic threshold, a graded warning is activated. The groundwater level monitoring equipment is as described above, and the position of the indicator head 114 can be measured using a position sensor.

[0025] Specifically: when the water level approaches the threshold, a blue alert is activated, indicating that water level changes require attention; the monitoring frequency is increased and reminders are pushed to the monitoring platform; When the water level reaches the threshold, a yellow alert is activated, which is to warn of changes in water level; local response measures are initiated (such as opening drainage pumps in high water areas and replenishing water in low water areas) and the local street office is notified; When the water level exceeds the threshold by less than 10%, an orange alert will be activated. The orange alert indicates an emergency and will close underground spaces in high-risk areas (such as subway entrances and exits to prevent flooding). When the water level exceeds the threshold by more than 10%, a red alert is activated. The red alert is an extreme situation that triggers a city-level emergency response and halts groundwater extraction.

[0026] The process of establishing a dynamic threshold for early warning water levels based on the historical hydrological patterns and seasonal characteristics of the region includes the following steps: S1. Obtaining Seasonal Baseline Thresholds: Obtain the highest and lowest safe groundwater levels for the area. The highest safe water level includes the highest safe water level for subways and underground utility tunnels, while the lowest safe water level includes the lowest water level for maintaining wetlands and river recharge. Group the groundwater by season and obtain the 90% confidence interval for the average water level in different seasons to obtain the water level fluctuation boundary for regular seasons. Introduce a safety redundancy coefficient α to determine the upper limit threshold H of the seasonal baseline. base，S，UP and seasonal baseline lower limit threshold H base，S，low ; S2. Perform functional zone correction: Divide the urban area into multiple functional zones according to water level risk sensitivity, and set an upper limit correction coefficient K for each functional zone. func,up and lower limit correction factor K func,low Through the seasonal baseline upper limit threshold H base,S,up Correction coefficient K for the upper limit of the corresponding functional area func,up The upper limit threshold H after functional correction is calculated. func,up Through the seasonal baseline lower limit threshold H base,S,low The lower limit correction coefficient K of the corresponding functional area func,low The lower limit threshold H after functional correction is calculated. func,low ; The formula for calculating the seasonal baseline upper limit is: H base，S，UP =min(H S，90%up (highest safe water level) / α; The formula for calculating the seasonal baseline lower limit is: H base，S，low =max(H S，90%low (Minimum safe water level) / α; Among them, H S This is the historical average; H base，S，UP H is the upper limit of the seasonal baseline threshold; base，S，low is the lower limit of the seasonal baseline threshold; S is the seasonal factor; S3. Under normal operating conditions, adjust the upper limit threshold H after functional modification. func,up And the lower limit threshold H after functional correction func,low As the final dynamic early warning threshold; under extreme operating conditions, an extreme operating condition correction coefficient K is introduced. extreme , respectively with the upper limit threshold H after functional correction func,up And the lower limit threshold H after functional correction func,low Multiplying these values ​​yields the final dynamic warning threshold under extreme conditions, which is the final upper limit threshold H.func,up and the final lower limit threshold H func,low ; Final upper limit threshold H func,up The formula is H func,up =H base，S，UP ×K extreme ; Final lower limit threshold H func,low The formula is H func,low =H func,low ×K extreme ; And the extreme working condition correction factor K extreme It will expire within 48 hours after the warning is lifted.

[0027] Among them, the various functional areas include: For subway or utility tunnel areas, the upper limit correction factor is 0.7-0.8, and the lower limit correction factor is 1.2-1.3. For core business districts or high-density residential areas, the upper limit adjustment factor is 0.8-0.9, and the lower limit adjustment factor is 1.0-1.1. For ordinary residential areas or science and education zones, the upper limit adjustment factor is 0.9-1.0, and the lower limit adjustment factor is 0.9-1.0. For suburban ecological zones, the upper limit correction factor is 1.1-1.2, and the lower limit correction factor is 0.8-0.9. For remote suburbs, the upper limit correction factor is 1.2-1.3, and the lower limit correction factor is 0.7-0.8.

[0028] In step S3, extreme operating conditions include extreme rainstorm conditions and extreme drought conditions; Among them, the extreme condition correction coefficient K for extreme rainstorm-type working conditions extreme The value ranges from 0.6 to 0.8; the extreme condition correction factor K corresponds to extreme drought conditions. extreme The value ranges from 0.8 to 0.9; the seasons include spring, summer, autumn and winter; when the season is spring, the value of S is 1; when the season is summer, the value of S is 2; when the season is autumn, the value of S is 3; when the season is spring and winter, the value of S is 4.

[0029] Based on the aforementioned monitoring and early warning methods, taking M City in southern China, which experiences heavy rainfall, as an example, excessively high groundwater levels can easily lead to water seepage in subway tunnels and flooding in the core area; meanwhile, industrial water use is stable in summer, and excessively low water levels may cause ground subsidence in the old city area. This calculation focuses on the summer of 2024 (S2, June-August), covering three typical functional areas in M ​​City: along Metro Line 3 (core sensitive area), the city center business district (core commercial area / high-density residential area), and the suburban wetland park (suburban ecological area).

[0030] Historical groundwater level data: Monthly average groundwater level data from 20 representative monitoring wells across the entire M city during the summer of the past 10 years (2014-2023) were collected. After removing outliers such as the "sudden rise of 1.5m in water level" caused by sensor malfunction in 2020 and the "sudden drop of 0.8m in water level" caused by temporary pipeline rupture in 2022, the following statistics were obtained: Historical average summer water level: 5.2m; 90% confidence interval for historical summer water level: upper limit (H) S,90%up =6.0m (excluding the highest 5% of extreme values ​​between 6.1 and 6.3m), lower limit \(H S,90%low =4.3m (excluding the lowest 5% of extreme values ​​between 4.0 and 4.2m); Obtain the hard boundary of urban safe water level (based on M City's "Groundwater Resources Protection Plan (2021-2030)"): Upper limit of infrastructure seepage resistance (subway tunnels, underground pipe corridors): 6.2m; Lower limit of ecological water level (river recharge, green space moisture retention): 3.5m; Determine the safety redundancy coefficient: The core area of ​​City M has dense infrastructure and high risk control requirements, so take α=1.15 (which meets the range of "1.1-1.2"). Substitute into the formula to calculate: Summer baseline upper limit threshold: H base,S2,up =min(H S,90%up (Safety hard boundary upper limit) / α=min(6.0,6.2) / 1.15≈5.2m; Summer baseline lower limit threshold: H base,S2,low =max(H S,90%low (Safety hard boundary lower limit) × α = max(4.3, 3.5) × 1.15 ≈ 4.9m The final threshold is calculated based on the functional area type: 1. Core sensitive areas, such as along Metro Line 3, with an upper limit correction factor K. func,up Set to 0.75, lower limit correction factor K func,low Set to 1.25; Calculate the corrected upper limit H func,up 5.2 × 0.75 = 3.9 m; Calculate the corrected upper limit H func,low : 4.9 × 1.25 = 6.1m.

[0031] 2. Core business districts, such as city center commercial areas (pedestrian streets), with an upper limit adjustment factor K. func,up Set to 0.85, lower limit correction factor K func,low Set to 1.05; Calculate the corrected upper limit H func,up 5.2 × 0.85 = 4.42 m; Calculate the corrected upper limit Hfunc,low : 4.9 × 1.05 = 5.145m.

[0032] 3. Suburban ecological zones, such as suburban wetland parks, with an upper limit correction factor K. func,up Set to 1.15, lower limit correction factor K func,low Set to 0.85; Calculate the corrected upper limit H func,up 5.2 × 1.15 = 5.98 m; Calculate the corrected upper limit H func,low : 4.9 × 0.85 = 4.165m.

[0033] Under normal operating conditions, the above calculation structure can be used to provide early warning of water levels. However, in extreme operating conditions, an extreme operating condition correction factor needs to be added. If City M issues a "red alert for heavy rain" and triggers extreme condition correction: Determine the correction factor for extreme operating conditions: Take K extreme =0.7; 1. Core sensitive area, calculate the upper limit threshold H under extreme operating conditions. func,up =3.9×0.7≈2.73m; Calculate the lower limit threshold H under extreme operating conditions func,low =6.1×0.7≈4.27m; 2. In the core business district, calculate the upper limit threshold H for extreme operating conditions. func,up =4.42×0.7≈3.094m; Calculate the lower limit threshold H under extreme operating conditions func,low =5.145×0.7≈3.6015m; 3. For suburban ecological zones, calculate the upper limit threshold H for extreme operating conditions. func,up =5.98×0.7≈4.186m; Calculate the lower limit threshold H under extreme operating conditions func,low =4.165×0.7≈2.9155m.

[0034] Based on the above calculations, an alarm will be issued when the water level reaches the corresponding value.

[0035] In the description of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0036] Those skilled in the art should understand that the above embodiments are merely for illustrative purposes and are not intended to limit the scope of this application. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of this application.

Claims

1. A groundwater level monitoring device, characterized in that: The monitoring equipment includes: The filter tube is inserted into the ground of the area to be tested at its bottom end and extends out of the ground of the area to be tested at its top end. The part of the filter tube that extends into the ground has holes, and the part of the filter tube with holes is covered with geotextile. A buoy extends into the filter tube from the top of the filter tube, and the top of the buoy has an indicator beacon; A transparent tube is installed at the top of the filter tube via a sleeve, with the lower half of the sleeve fitted over the top of the filter tube and the upper half fitted over the bottom of the transparent tube. A scale is installed on the inner wall of a transparent tube, and the scale has graduation marks, with the top of the indicator corresponding to the graduation marks.

2. The groundwater level monitoring equipment according to claim 1, characterized in that: The indicator includes a standard rod and a connector, the standard rods being detachably connected to each other via the connector, wherein the lowest standard rod is fixedly connected to the buoy; The connector includes an iron plate and a nut. The iron plates are arranged in pairs, and there are two nuts welded to the inner sides of the upper and lower ends of the two iron plates. The end of the standard rod has an external thread section that is adapted to the nut. The top of the standard rod at the very top is also equipped with an indicator head, which corresponds to the scale markings.

3. A method for monitoring and early warning of urban groundwater levels, characterized in that: The monitoring method includes: Groundwater level monitoring equipment is distributed and installed in the areas to be monitored, and a dynamic threshold for warning water level is established based on the seasonal characteristics and historical hydrological patterns of the area; when the monitored water level reaches or exceeds the dynamic threshold, a graded warning is activated. The process of establishing a dynamic threshold for early warning water levels based on historical hydrological patterns and seasonal characteristics of the region includes the following steps: S1. Obtaining Seasonal Baseline Thresholds: Obtain the highest and lowest safe groundwater levels for the region; group by season and obtain the 90% confidence interval for the average water level under different seasons to obtain the water level fluctuation boundary in the normal season; introduce a safety redundancy coefficient α to determine the upper limit threshold H of the seasonal baseline. base，S，UP and seasonal baseline lower limit threshold H base，S，low ; S2. Perform functional zone correction: Divide the urban area into multiple functional zones according to water level risk sensitivity, and set an upper limit correction coefficient K for each functional zone. func,up and lower limit correction factor K func,low Through the seasonal benchmark upper limit threshold H base,S,up Correction coefficient K for the upper limit of the corresponding functional area func,up The upper limit threshold H after functional correction is calculated. func,up The seasonal baseline lower limit threshold H base,S,low The lower limit correction coefficient K of the corresponding functional area func,low The lower limit threshold H after functional correction is calculated. func,low ; S3. Under normal operating conditions, the upper limit threshold H after the function is corrected. func,up And the lower limit threshold H after functional correction func,low As the final dynamic early warning threshold; under extreme operating conditions, an extreme operating condition correction coefficient K is introduced. extreme , respectively with the functionally corrected upper limit threshold H func,up And the lower limit threshold H after functional correction func,low Multiplying these values ​​yields the final dynamic warning threshold under extreme conditions, which is the final upper limit threshold H. func,up and the final lower limit threshold H func,low ; The groundwater level monitoring equipment is the same as described in claim 1 or 2.

4. The urban groundwater level monitoring and early warning method according to claim 3, characterized in that: The various functional areas include: For subway or utility tunnel areas, the upper limit correction factor is 0.7-0.8, and the lower limit correction factor is 1.2-1.

3. For core business districts or high-density residential areas, the upper limit adjustment factor is 0.8-0.9, and the lower limit adjustment factor is 1.0-1.

1. For ordinary residential areas or science and education zones, the upper limit adjustment factor is 0.9-1.0, and the lower limit adjustment factor is 0.9-1.

0. For suburban ecological zones, the upper limit correction factor is 1.1-1.2, and the lower limit correction factor is 0.8-0.

9. For remote suburbs, the upper limit correction factor is 1.2-1.3, and the lower limit correction factor is 0.7-0.

8.

5. The urban groundwater level monitoring and early warning method according to claim 4, characterized in that: ； The formula for calculating the upper limit of the seasonal benchmark is: H base，S，UP =min(H S，90%up (highest safe water level) / α; The formula for calculating the lower limit of the seasonal benchmark is: H base，S，low =max(H S，90%low (Minimum safe water level) / α; Among them, H S This is the historical average; H base，S，UP H is the upper limit of the seasonal baseline threshold; base，S，low is the lower limit of the seasonal baseline threshold; S is the seasonal factor.

6. The urban groundwater level monitoring and early warning method according to claim 5, characterized in that: Final upper limit threshold H func,up The formula is H func,up =H base，S，UP ×K extreme ; Final lower limit threshold H func,low The formula is H func,low =H func,low ×K extreme ; And the extreme condition correction coefficient K extreme It will expire within 48 hours after the warning is lifted.

7. The urban groundwater level monitoring and early warning method according to claim 6, characterized in that: In step S3, the extreme operating conditions include extreme rainstorm conditions and extreme drought conditions; Among them, the extreme condition correction coefficient K for extreme rainstorm-type working conditions extreme The value ranges from 0.6 to 0.8; the extreme condition correction factor K corresponds to extreme drought conditions. extreme The value ranges from 0.8 to 0.

9.

8. The urban groundwater level monitoring and early warning method according to claim 3, characterized in that: The highest safe water level includes the highest safe water level for subways and underground utility tunnels; The minimum safe water level includes the minimum water level required to maintain wetland and river replenishment.

9. The urban groundwater level monitoring and early warning method according to claim 3, characterized in that: The seasons include spring, summer, autumn, and winter; When the season is spring, S takes the value of 1; when the season is summer, S takes the value of 2; when the season is autumn, S takes the value of 3; when the season is spring and winter, S takes the value of 4.

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