61 results about "River flood" patented technology

The invention relates to a quick river flood forecasting method based on a physical information neural network, and belongs to the field of river flood forecasting. The method comprises the following steps: on the basis of a traditional physical information neural network (PINN), introducing a boundary condition parameter as an input variable, and enabling the PINN to learn a flood wave propagation rule under different boundary conditions. Furthermore, on this basis, a physical information neural network flood fast forecasting framework (RFF-PINN) integrated with a hydrodynamic method is provided, a numerical solution based on grid discretization is reconstructed into a continuous function in a time-space domain through a piecewise polynomial interpolation method, residual error loss between network output and a hydrodynamic model simulation value is constructed, and therefore, a flood fast forecasting result is obtained. The network parameters are optimized in cooperation with the PDE loss, and the problem that the network parameter optimization effect is reduced due to the fact that the PDE loss of the complex flow state area is difficult to converge is solved. The method has the beneficial effect that the water depth change process of each section of the river channel under any boundary condition can be accurately and quickly predicted.

The invention relates to a mountain river flood dynamic rehearsal method, device and equipment based on big data fusion and a medium. The method comprises the following steps: acquiring a multi-source fusion data set of a target mountain river; based on the multi-source fusion data set, recognizing the flood type of the target mountain river in combination with a preset threshold rule to obtain the flood type and cause parameters; according to the flood type and the cause parameter, calculating a design flood peak flow value of each node in the target mountain river; according to each design flood peak flow value, performing section-by-section trial calculation through an energy equation to obtain a design flood surface line; and performing dynamic simulation processing on the flood routing process of the target mountain river based on the designed flood water surface line, and generating a flood routing dynamic simulation report of the target mountain river. The method can accurately adapt to the characteristics of diverse causes and complex propagation process of flood in a mountain river, and remarkably improves the refinement degree and reliability of flood rehearsal.

The invention discloses a river flood control influence analysis method based on a graph neural network, and the method comprises the following steps: S1, collecting terrain, hydrology, weather and water flow data, and constructing a graph structure model; s2, generating node and edge features, and forming a graph model; s3, inputting the graph model to a Laplacian network, and generating graph feature representation; s4, combining real-time data updating features, and constructing a dynamic graph model; s5, executing neighborhood sampling, and constructing a local subgraph; s6, inputting an attention mechanism, and generating an attention graph representation; s7, inputting a graph generation module, simulating a flood situation, and generating an expansion graph structure; and S8, training the dynamic graph model, and outputting a flood range, a risk level and flood control measures. According to the invention, graph modeling and reasoning integration of flood control analysis is realized.

The invention provides a hydrodynamic model-based mountain river flood diversion tunnel line and scale optimization design method, which comprises the following steps of: constructing a one-dimensional hydrodynamic mathematical model of a research area drainage basin by adopting MIKE11 software, and constructing a one-dimensional hydrodynamic model of the research area drainage basin according to the one-dimensional hydrodynamic mathematical model of the drainage basin, boundary conditions and calibrated comprehensive roughness; and calculating designed flood water surface lines of different frequencies of the urban section. According to the actual situation of a city, aiming at urban flood causes and main problems existing in a current flood control system, engineering measure schemes such as flood control reservoir construction, beach retreating and river returning, river regulation, embankment heightening and flood diversion channel building are proposed, and a flood diversion tunnel route and planning optimization research is developed on the basis of a hydrodynamic model. Numerical simulation of flood disasters is completed by means of the modern information technology, a complete disaster prevention and control system is established for achieving the purposes of scientization, high efficiency and automation of disaster prevention and relief decision, the urban flood prevention capacity can be comprehensively improved, and the life and property safety of the masses is guaranteed.

The invention discloses an embankment gushing risk evaluation method based on an embankment gushing formation mode, and the method comprises the steps: constructing the formation mode of the embankment gushing risk through employing the outboard flood occurrence probability as a triggering premise, employing a riverbed instability coefficient as a disaster-causing factor, and employing the stability degree of an embankment as a resistance capability; according to the calculation method for obtaining the embankment gushing risk according to the evaluation model, the embankment gushing risk can be quantitatively analyzed and calculated, the embankment gushing risk point can be effectively recognized, the weak river reach of the embankment can be defended in a targeted mode, passive water safety incident handling is changed into active water safety risk prevention and control, and the method is the key for guaranteeing the flood control safety of the river channel. And the method is universal for safety protection of other river dikes in the world, and has popularization significance.

The application relates to a river flood discharge capacity dynamic evaluation and hydrological early warning method. The method comprises the following steps: based on a parameter sensitive observation subset, sequentially updating an initial hidden variable in a low-dimensional hidden space through an unscented particle filter algorithm to obtain an optimized hidden variable, and inputting the optimized hidden variable into a river dynamic resistance field generator based on an initial dynamic roughness field to perform decoding processing to obtain a dynamic roughness field of a current period; based on the dynamic roughness field and a state sensitive observation subset, performing analysis and update processing on a state variable field of a hydrodynamic model through a deterministic ensemble Kalman filter algorithm to obtain an assimilated water level field and a flow velocity field; according to the water level field, the flow velocity field and the dynamic roughness field, the maximum flood discharge capacity of a section is calculated in combination with dike top elevation data, and a flood discharge capacity dynamic index is calculated based on the maximum flood discharge capacity of the section and a current actual flow. The method can realize real-time dynamic quantification of river flood discharge capacity and predictive evaluation of flood risk.

The invention discloses a device and a method for testing influence of river and canal flood on variable slope pipe network drainage and ground surface submerging, and relates to the field of urban flood. A water tank lifting assembly can ascend and descend, and a water tank can move relative to the water tank lifting assembly, so that the gradient of the water tank can be adjusted; the inspection well lifting assembly can ascend and descend and can move so that the gradient of the underground pipe network can be adjusted, the effluent weir comprises a weir plate which can move in the height direction of the testing device, and the weir plate is used for adjusting the water level in the river channel. Therefore, the gradient of the water tank is adjusted through the water tank lifting assembly, the gradient of the underground pipe network is adjusted through the inspection well lifting assembly, and the weir plate is used for adjusting the water level in the canal. The test device can accurately simulate the influence degree of the dynamic change of the water level of the canal on the drainage of the urban variable-gradient pipe network and the range and depth of surface submerging under the combined situation of different surface incoming flows and pipeline incoming flows, and provides decision support for urban flood risk management and urban drainage system design.

The present invention discloses a portable flow measuring device for hydrological testing, which belongs to the field of detection technology. The device includes a box A, a box B and a drive assembly. Radar flowmeters and acoustic Doppler flowmeters are installed on both sides of box B, and box A moves along a rod or rope through the drive assembly. The detection and balancing system collects environmental parameters in real time, such as water surface roughness, wind speed, particle content, water depth, etc., constructs radar and acoustic confidence models through normalization processing, dynamically allocates sensor weights in combination with the height change function, and finally outputs high-precision detection results through the flow rate model. The present invention solves the problem of insufficient reliability of a single sensor in a complex environment through multi-source data fusion and adaptive algorithms. It has the advantages of portability, robustness and high precision, and is suitable for river, flood and field hydrological monitoring.

The invention relates to the field of flood control risk prediction, in particular to a river flood control risk prediction analysis system based on a water conservancy model, and the system is provided with a twinborn monitoring module which is used for continuously obtaining water conservancy data of a target river region according to a preset monitoring frequency, and constructing a corresponding twinborn model; the feature recognition module is connected with the twinborn monitoring module and is used for analyzing collapse features based on a twinborn model; the type division module is connected with the feature recognition module and is used for evaluating a diffusion characterization value according to the collapse features in combination with the minimum distance between the edges of the adjacent sunken regions so as to divide the diffusion tendency types of the sunken regions; and the prediction analysis module is connected with the type division module and is used for adaptively detecting and analyzing the sunken area based on the diffusion tendency category, the detection efficiency of the dike breach is improved, and then support is provided for implementation of rapid plugging.

The invention belongs to the technical field of hydrological forecasting, and discloses a river flood forecasting method, system, equipment and medium based on a hydrological model, and the method comprises the steps: obtaining the historical hydrological data of a research area, carrying out the rainfall-runoff trend analysis of the research area based on the historical hydrological data, and obtaining the historical rainfall runoff data of the research area; interpolating the rainfall capacity of the research area based on rainfall data in the historical rainfall runoff data to obtain a rainfall spatial distribution diagram of the research area; performing watershed digitization by using watershed original DEM data of the research area to obtain river network form information after sub-watershed division, and calculating a CN value of each sub-watershed; constructing a river flood forecasting model; and inputting the real-time hydrological data of the research area into the river flood forecasting model for forecasting to obtain a forecasting result, and finishing forecasting. According to the technical scheme of the invention, a numerical weather forecasting and hydrological model coupled flood forecasting system can be constructed, and the forecasting period can be effectively prolonged.

The present application belongs to the technical field of water conservancy engineering, and provides a river flood control and drainage system, including a pump station, a screen cleaner, a sand pump, a first auger loosener and a crushing assembly; the sand pump and the first auger loosener are both arranged near the riverbed, and the sand pump is located between the gate of the pump station and the grille of the screen cleaner; the first auger loosener is located on the side of the screen cleaner away from the sand pump; the crushing assembly includes a first wolf tooth roller and a second wolf tooth roller, and the rotating shafts of the first wolf tooth roller and the second wolf tooth roller are both perpendicular to the riverbed. The river flood control and drainage system of the present application can use the crushing assembly to squeeze and crush the stones and large-volume debris mixed in the flood into small-volume fragments, and clean them through the screen cleaner; the first auger loosener is used to stir the sediment in the flood to avoid sedimentation, and at the same time, it is combined with the sand pump for cleaning, thereby solving the problem of cleaning sediment and stones during flood control and drainage, and improving the continuous operation capability of the facility.

The invention discloses a self-adjusting water gate structure based on a river flood season, which comprises a gate body, a gate plate capable of moving up and down is arranged in the gate body, the self-adjusting water gate structure further comprises a blocking assembly, a shifting assembly and a fishing assembly, the blocking assembly can move up and down along with the water surface, and part of the blocking assembly can float on the water surface; and the other part of the blocking assembly can be inserted into the water surface. During use, the gate body is installed in a water body, sundries such as branches can float on the water surface due to small buoyancy, the blocking assembly can block the sundries so as to prevent the sundries from penetrating through the gate body, and when the sundries are accumulated to a certain degree, the stirring assembly can stir the sundries so that the blocking assembly can rotate, and the sundries can be prevented from penetrating through the gate body. The blocking assembly is arranged on the water surface so that sundries floating on the water surface can be taken away from the water surface, then the fishing assembly can remove the sundries on the blocking assembly, and therefore the purpose of cleaning the sundries on the water surface is achieved, and after cleaning is completed, the blocking assembly is reset for use next time.

The present application relates to the technical field of river basin water environment management and water ecological evaluation, and particularly relates to a river flood season pollution impact evaluation method and system combining river basin spatial analysis and water ecological response. The method first collects water ecological data, pre-processes the water ecological data, calculates the water ecological metabolism background value before the non-flood season or the flood season pollution event based on the diurnal variation model of river dissolved oxygen concentration based on mass balance, calculates the theoretical lag time from rainfall to pollution peak value based on the correlation between the catchment area and the response time, and delimits the flood season pollution event window period. Based on the high-frequency monitoring data of the water ecology in the flood season pollution event window period, the water ecological metabolism response index is calculated, the disturbance intensity of the pollution event on the water ecological system metabolism function is evaluated, the non-point source pollution intensity index and the point source risk evaluation value are calculated, and the pollution source investigation suggestion is comprehensively generated. The present application effectively solves the problem of difficult definition of non-point source pollution responsibility in the flood season, and realizes the accurate identification of pollution sources.

The invention relates to the technical field of river channel flood discharge, and discloses a river channel flood discharge capacity improving method and device for a plain river network district, and the method comprises the steps: obtaining the upstream and downstream water surface ratio drop, the overflowing flow, the water level of regions on both banks and the submerging condition of both banks of a target flood discharge river channel in the plain river network district in a historical flood discharge period; the upstream and downstream water surface gradient, the overflowing flow, the water levels of the areas on the two banks and the submerging conditions of the two banks are analyzed, and the flood discharge level of the target flood discharge river channel is determined; if the flood discharge level of the target flood discharge river channel does not conform to the flood discharge capacity of the flood discharge river channel design, the pump station design flow and the pump station stage number are obtained, and a multi-stage relay water lifting pump station arrangement scheme is determined based on the pump station design flow and the pump station stage number; and the pump stations in the target flood discharge river channel are scheduled and operated by using the multi-stage relay water lifting pump station layout scheme. The flood discharge capacity of the river channel in the plain river network area is improved, and flood disaster loss and influence are reduced.

The invention relates to a water level real-time monitoring mechanism for river flood control. The water level real-time monitoring mechanism comprises a vertically-arranged monitoring column, a display part vertically and fixedly installed at the top of the monitoring column and an indication assembly installed between the monitoring column and the display part. A plurality of display areas are sequentially arranged on the display part from top to bottom; the indicating assembly comprises a vertical track fixedly installed on the monitoring column, a connecting rod slidably installed in the track, a buoyancy piece fixedly installed at the bottom of the connecting rod, and an indicating piece fixedly installed at the top end of the connecting rod and used in cooperation with the display piece. The system has the advantages that full-process automation from water level monitoring, visual warning and graded triggering to equipment self-maintenance is achieved, and the real-time performance and reliability of river flood prevention monitoring are remarkably improved.

This application discloses a river functional vulnerability assessment method, equipment, medium, and product, relating to the technical fields of water conservancy projects and river ecological assessment. The method comprises: obtaining basic river information; determining indicator data for river functional vulnerability assessment; constructing a judgment matrix for the indicator data using the analytic hierarchy process (AHP); calculating a weight vector for the indicator data based on the AHP; quantifying and assigning scores to the indicator data based on the basic river information and river flood control standards to obtain a scoring result; and calculating a comprehensive functional score for the river based on the weight vector and the scoring result. The comprehensive functional score is used to assess river functional vulnerability. By introducing the AHP and a multi-indicator scoring system, this application constructs a comprehensive evaluation system for river flood control, navigation, water supply, and ecology. This system can more scientifically and comprehensively reflect river functional vulnerability and provide a reference for river management and governance.

The present application relates to the technical field of hydrological simulation, and more particularly to a rainfall-runoff-concentration-evolution whole-process dynamic simulation system and method. The method comprises the following steps: obtaining basin topographic information and extracting basin boundaries; dividing grid cells according to the basin boundaries and setting river nodes using the grid cells; collecting rainfall data using a rain measurement radar; calculating runoff using the rainfall data; inputting the runoff into a pre-trained distributed concentration model for concentration analysis and recording the concentration flow; inputting the concentration flow and the river nodes into a river flood evolution model to perform river evolution simulation and generate river concentration data; determining the amount of water entering the main river according to the river concentration data; generating a flow time series according to the amount of water entering the main river; and predicting the flood peak flow based on the flow time series. The present application realizes accurate simulation of the hydrological process of a basin based on hydrological simulation technology, and improves the accuracy and timeliness of flood prediction and early warning.

The application discloses a navigation facility. The navigation facility comprises a deep navigation channel and a semi-submersible floating ship loader. The deep navigation channel is formed at the bottom of a normal navigation channel and passes through a bridge crossing a navigation channel. The semi-submersible floating ship loader is configured to float in the deep navigation channel with a controllable draught and is used for carrying a ship through the bridge crossing the navigation channel. The technical scheme provided by the application can solve the navigation requirement under the condition that the height of an existing bridge is limited, and also meets the requirements of not affecting the normal use of the bridge, river flood discharge in flood season, fish migration and the like.

A river flood prevention early warning system comprises a master control terminal and a monitoring terminal, the monitoring terminal comprises a vertical rod arranged on a reference plane, the vertical rod is connected with a radar water level gauge through a cross rod, and the radar water level gauge is located above a monitored liquid level; the vertical rod is a hollow rod, an alarm emitter and a storage battery are arranged at the position, higher than the datum plane, of an inner cavity of the vertical rod, the alarm emitter and the storage battery are not in contact, electric contact pieces are oppositely arranged on the adjacent sides of the alarm emitter and the storage battery, the position of the alarm emitter is fixed, and the storage battery is provided with a traction rope and is fixed to the hook through a water dissolving ribbon. And the storage battery can be electrically connected with the alarm transmitter after the water-soluble cable tie is broken. On the basis of existing flood prevention equipment, an alarm emitter and a storage battery which is used in cooperation with the alarm emitter and is fixed through a water dissolving ribbon are added, and after the water level reaches a certain height, after the water dissolving ribbon is dissolved, the storage battery can make contact with the alarm emitter, and then a water level early warning signal is sent out.

The invention belongs to the technical field of drainage, and particularly discloses a river flood prevention emergency rescue emergency drainage device which comprises a water suction pump, a water suction assembly is arranged at the end of a water suction pipe of the water suction pump, the water suction assembly comprises a square pipe, and two square frames are symmetrically installed on the surface of the square pipe; water inlet grooves are formed in the four end faces of the square frames correspondingly, first filter plates are installed in the water inlet grooves through rotating shafts, movable frames are movably installed on the surfaces of the square pipes and movably installed between the two square frames, and pushing plates are fixedly installed on the surfaces of the movable frames. A pushing plate is installed on the bottom of the square pipe, the pushing plate corresponds to an opening of the water inlet groove, supporting frames are installed at the two ends of the bottom of the square pipe, and a driving assembly is arranged between the two supporting frames and located under the square pipe. Therefore, the flood prevention and drainage efficiency and reliability are improved.

The invention discloses a river flood prevention protection device and a flood prevention protection method, and belongs to the technical field of river flood prevention. A river flood prevention protection device comprises a fixing frame, a flashboard is arranged in the fixing frame in a sliding mode, a hoist for lifting the flashboard is arranged on the fixing frame, a plurality of water permeable holes are formed in the flashboard, a blocking structure for blocking the water permeable holes is arranged on the downstream face of the flashboard, and a cleaning mechanism for cleaning garbage on the water surface is arranged on the upstream face of the flashboard. A lifting plate is slidably arranged in the gate plate, a lifting structure for lifting the lifting plate is arranged on the gate plate, and a transmission structure for driving the plugging structure to move is arranged between the lifting plate and the plugging structure. By the adoption of the river flood prevention protection device and method, the problems that an existing flood prevention device is fixed in height and poor in flood prevention and water passing effects can be solved; and garbage on the river surface can be intercepted and cleaned, and pollution of the garbage to a downstream river channel is relieved.

The application discloses a river overflow flood evolution rapid simulation method based on river self-adaptive segmentation and strong water quantity balance constraint, realizes rapid and fine simulation of river overflow flood in a basin through the following execution processes of basin basic data collection and processing, river overflow flood inundation rapid calculation model construction, river overflow flood rapid prediction and risk analysis, meets the requirements of 'four predictions' of basin flood control fine simulation simulation, real-time early warning and prediction, rapid scenario deduction and the like, and can also serve basin flood control planning and design.

The application provides a river flood season pollution intensity prediction and early warning method and system, relates to the technical field of water conservancy projects, and the method comprises the following steps: acquiring multi-source data in a basin, and preprocessing the multi-source data; constructing a hydrological water quality model for calculating the hydrological cycle process of the entire basin from the upstream to the downstream; calculating the point source and area source pollution load to obtain water quality concentration; constructing a prediction data set according to the water quality concentration, and training an XGBoost machine learning model by using the prediction data set; and predicting the pollutant concentration in the flood season under the influence of different meteorological conditions and carrying out over-standard concentration early warning by using the trained XGBoost machine learning model. The application can predict the short-term river water quality change peak value in advance by fusing meteorological prediction, a hydrological model and real-time monitoring data, realize early warning of water quality change, and finally integrate into a basin management decision platform to realize early regulation and control of the management department and pre-control of pollution.

The invention relates to the technical field of river channel flood control, in particular to a river channel control flood control method.The flood control device comprises a base, fixing assemblies are symmetrically arranged on the base, and the fixing assemblies can fix the base to the ground; the protection plate is arranged on the base, a plurality of flow guide grooves are formed in the protection plate, a limiting assembly connected with the protection plate is arranged on the base, and the limiting assembly can limit the rotating angle of the protection plate; the supporting mechanisms are symmetrically arranged on the base and connected with the protection plate, and the supporting mechanisms can move when the protection plate is impacted; the strength adjusting mechanism is arranged on the base and connected with the supporting mechanism, and the supporting mechanism can drive the strength adjusting mechanism to move so as to adjust the supporting state of the supporting mechanism on the protection plate; and the flow guide assembly is arranged on the base and connected with the strength adjusting mechanism and the protection plate.

The invention provides a multi-disaster multi-mode flood flow intelligent monitoring and early warning method, system and device, and relates to the field of disaster early warning. Establishing a rainstorm-runoff coupling model for predicting the surface runoff yield, the confluence time and the runoff peak value based on the soil water content, the vegetation coverage and the surface slope data under different rainfall capacities; constructing a river channel confluence coupling model based on the flow velocity, the water level and the section form of river channel section monitoring for predicting river channel flood confluence time, confluence amount and on-way water level change; judging whether there is a riverway confluence risk according to the real-time predicted riverway flood confluence time, confluence amount and on-way water level change; when the riverway confluence risk exists, the flood inundation range, the water depth distribution and the evolution speed are predicted through a pre-trained flood evolution coupling model based on the surface runoff, the confluence time and the change speed of the runoff peak value in combination with the landform data. According to the invention, the accuracy, timeliness and reliability of disaster early warning can be improved.

This invention discloses a dynamic assessment device and method for river flood risk and unmanned precision dredging, relating to the field of water conservancy and river management technology. The device includes: an unmanned high-frequency mapping unit, an intelligent analysis and decision-making unit, an unmanned precision dredging unit, and an on-shore sludge treatment and disposal unit. Each unit is bidirectionally connected to the intelligent analysis and decision-making unit. The unmanned high-frequency mapping unit is a lightweight unmanned surface vessel (USV) equipped with a multibeam echo sounder and other equipment to collect terrain data and construct models. The intelligent analysis and decision-making unit is deployed on-shore or in the cloud, processing data and issuing dredging commands. The unmanned precision dredging unit is a dynamically positioned USV integrating variable depth suction and other mechanisms. The on-shore sludge treatment and disposal unit receives and processes dredged sludge through a sealed structure. This invention features a multi-architecture compatible hardware layout and a dual-threshold PID precision dredging process, achieving centimeter-level depth control and closed-loop sludge transport, protecting the original riverbed soil layer, reducing energy consumption and management investment, and stabilizing the river's flood discharge capacity.

The invention relates to the technical field of water conservancy informatization and flood prevention and disaster reduction, in particular to a river flood routing simulation and flood prevention emergency decision support system and method.The system comprises edge space-time reference nodes deployed at key flood prevention nodes and a central decision correction server, and the data acquisition module is used for acquiring state data such as sluice opening and personnel transfer and executing a control instruction, and the control instruction is used for aligning heterogeneous data through a high-precision timestamp, constructing a digital twinning situation under a unified space-time reference, dynamically correcting a hydrodynamic model boundary condition based on an instruction execution deviation, and triggering resimulation and emergency decision updating. The invention provides a river flood routing simulation and flood prevention emergency decision support system and a river flood routing simulation and flood prevention emergency decision support method, which solve or at least alleviate the problem that a simulation result is disjointed from reality due to the lack of closed-loop feedback and unified time reference in simulation deduction and physical execution in an existing system.

The invention discloses a flood routing simulation method, device and equipment in a dike burst scene and a medium. The method comprises the following steps: receiving breach definition data for a target breach input by a user on a front-end interactive interface through clicking; judging whether the target breach is completely located in an initial calculation range of a river flood routing model or not on the basis of the breach definition data and the preprocessed breakwater burst exchange data; if yes, directly utilizing a pre-constructed river flood routing model to carry out analog simulation calculation of flood routing; if not, reconstructing a river flood routing model, and performing analog simulation calculation of flood routing; and transmitting an analog simulation calculation result to a front-end interaction interface, and outputting and displaying a dynamic result of flood routing simulation in a dynamic rendering manner. According to the embodiment of the invention, by collecting the basic data of the drainage basin, interactively setting the dike burst parameters, adjusting the simulation area and visualizing the simulation result in real time, the response speed and decision support capability of drainage basin dike burst flood simulation are improved.

The invention relates to the technical field of river flood routing, in particular to a dynamic display method for a river flood routing grid model based on a three-dimensional scene. The method comprises the following steps: obtaining a section data set of a river channel, river channel hydrological boundary condition data and river network topological relation data; constructing a four-point implicit grid according to four nodes of two continuous moments of adjacent sections in the section data set, and performing weighted differential discretization on the Saint-Venant equation set on the four-point implicit grid to obtain a standard differential form; substituting a preset linear hypothesis relational expression into a preset standard differential form, and deducing to obtain a recursion formula of the sensitivity coefficient and the correction coefficient; and determining an initial coefficient according to the hydrological boundary condition data of the upstream river channel, and calculating the coefficient of each section on the four-point grid section by section by using the initial coefficient and a recursion formula. According to the method, accurate recursion of the water level and the flow of each section is realized through four-point implicit grid construction and Saint-Venant equation weighted difference discrete calculation.