Abstract:Based on continuous 10-year precipitation monitoring data from 2014 to 2023 in Xinfu District,a systematic analysis of the composition characteristics,pollution types,and sources of water-soluble ions in the atmospheric precipitation of the region was carried out.The results show that the precipitation in Xinfu District is generally neutral,and the electrical conductivity(EC)is influenced by a variety of environmental factors.The dominant anions in the precipitation are SO42-and NO3 ⁻,while the dominant cations are Ca2+and Na+,indicating that Ca2+and Na+are the main ions neutralizing the acidic substances in the precipitation.The SO42-/NO3⁻ ratio in the precipitation over the years ranges from 5.1 to 17.3(much greater than 3),showing typical coal-burning(sulfuric)pollution characteristics.Ion correlation and source contribution analysis confirmed that K+and Ca2+are primarily influenced by terrestrial inputs,Mg2+is affected by both marine and terrestrial sources,and 98.2%of Cl ⁻ originates from the ocean.SO42-and NO3 ⁻ are mainly from anthropogenic sources(with SO42-also influenced to some extent by the ocean),and the contribution of anthropogenic sources to NO3⁻ is as high as 98.0%.

Abstract:The Happy River and Lake Construction of Minghu Lake Project in Chuzhou,Anhui Province,is one of the first batch of Happy Rivers and Lakes construction projects initiated by the Ministry of Water Resources.The project practices the development philosophy of"lucid waters and lush mountains are invaluable assets".In response to the deficiencies in water environment quality,water ecological status,water resource allocation,water security assurance,and the inheritance of water culture in Minghu Lake,the project follows the principle of"overall planning and systematic governance"to carry out systematic and comprehensive governance of the Minghu Lake watershed.This paper analyzes and discusses the implementation plan for the Happy River and Lake construction of Minghu Lake from the perspectives of river-lake system governance,management and protection capability enhancement,and support for regional watershed development,aiming to provide ideas and references for promoting high-quality watershed water conservancy development,enhancing people's sense of gain and happiness,and enriching the connotation of river and lake water culture.

Abstract:In order to comprehensively understand the aquatic ecological condition of the Miyun Reservoir,this paper systematically analyzes the eutrophication level,phytoplankton,macrophytes,zooplankton,and benthic organisms based on the monitoring data from 2021 to 2023 in the reservoir area.The results show that,as of 2023,both the reservoir area and the incoming water bodies are at a moderate level of eutrophication.A total of 7 phyla and 79 genera of phytoplankton were identified in the reservoir,with dominant species in the year being Asterionella formosa,Synura petersenii,and Anabaena flos-aquae.A total of 54 species of macrophytes were found,with an increase in species diversity(18 additional species)and improved coverage.The disappearance or extinction phenomenon is gradually recovering.The total density of zooplankton increased,but species diversity decreased,with dominant species mainly belonging to the Phylum Rotifera,and the species density showed significant seasonal variation.Benthic organisms are primarily pollution-tolerant species,with higher numbers and species in relatively shallow areas compared to deep areas.However,the species composition is simple,and mollusks are rare.The study results provide theoretical support and data for the eutrophication control and aquatic ecological protection of the Miyun Reservoir.

Abstract:The secondary development of reservoirs is of great significance for improving economic benefits.Through technical improvements,the Central Guizhou Water Conservancy Hub Project adopted the approach of replacing the"ecological discharge facility cone valve"with an"ecological hydroelectric generator"(hereinafter referred to as"machine substitution for valve").This method fully utilized water resources for power generation,increasing the economic benefits of the project while replacing high-head energy dissipation measures.By employing a reasonable scheduling and operation method that alternated water discharge with the originally approved large units,the ecological water demand of downstream rivers was met.Following program demonstration,the technical and economic aspects were found to be reasonable and feasible.The modification was approved by relevant departments,and the system has been in operation for many years,generating considerable revenue.Operational practice confirmed that using the reservoir's ecological water energy for power generation through"machine substitution for valve"significantly increased economic benefits and enriched the avenues for secondary development of reservoirs,providing valuable experience for similar projects.

Abstract:Extreme rainfall events can lead to an increase in pollutant concentrations in semi-closed water bodies,thereby increasing the risk of eutrophication.This paper selected three intense rainfall events in the Phase Ⅱ of the Songzhuang Flood Retention Area in Beijing,where the rainfall intensity exceeded 120 mm/h during the summer of 2023-2025.The trends of water quality indicators such as ammonia nitrogen,total phosphorus,chemical oxygen demand,electrical conductivity,and turbidity were analyzed based on monitoring data.The results show that various water quality parameters changed to different extents before and after the intense rainfall events.Compared to the median values before the rainfall,the peak median values of water quality parameters during the three intense rainfall events showed the following changes:ammonia nitrogen concentration increased by 40％,total phosphorus concentration increased by 21％,chemical oxygen demand increased by 11％,electrical conductivity decreased by 10％,and turbidity increased by 452％.The study results indicate that intense rainfall has a significant impact on the water quality of semi-closed water bodies,providing valuable reference for pollution prevention and water quality management in semi-closed water bodies under extreme weather conditions.

Abstract:As a border hub and multi-ethnic settlement,the central urban area of Mengla County faces multiple challenges including water source quality risks,insufficient water supply capacity,and rural drinking water safety,with the contradiction between water supply and demand becoming increasingly prominent.Focusing on the development needs of 2035,this paper conducts water supply-demand analysis and allocation research,aiming to establish a safe,reliable,efficient,and intensive multi-source complementary water supply system with quality-based and categorized water distribution to support the sustainable development of towns in border ethnic areas.The per capita daily water consumption method,quota method,and land-use index method are adopted for categorized water demand forecasting.Water availability is calculated based on long-term hydrological series data.Scheme comparison and demonstration are carried out through multi-source water supply comparison,supply-demand balance analysis,quality-based water allocation,and total water use control verification.The results indicate that under the P=95%extreme dry year scenario in 2035,the total water demand of the central urban area is 19.289 million m3,while the total available water supply from existing and planned sources is 14.843 million m3,resulting in a deficit of 4.446 million m3.The Mandan Reservoir is unsuitable as a domestic water source due to unstable water quality caused by non-point source pollution.With the newly constructed Nanxihe Reservoir supplying 4.446 million m3 annually,combined with the Mandan Reservoir,Manzhang Reservoir,Nanxihe Water Diversion Project,and reclaimed water,the multi-source allocation scheme can fully guarantee all types of water demand.This scheme meets the regional total water use control requirements and is technically sound and economically feasible.

Abstract:As an important component of reservoir hubs,dams serve as a crucial physical barrier for regulating reservoir water levels.Due to their favorable economic efficiency and construction convenience,earth-rock dams are widely used.The structural design of earth-rock dams is constrained by various stability issues,among which seepage stability and anti-sliding stability are particularly prominent.During the structural design process of earth-rock dams,it is necessary to consider the operating conditions of the reservoir dam and carry out verification of seepage stability and anti-sliding stability through numerical simulation.Based on an actual engineering example,this paper conducts verification of seepage stability and anti-sliding stability of an earth-rock dam using the GeoStudio numerical simulation platform,which can provide reference for similar engineering verification.

Abstract:The flood diverting hub of Lugou Bridge on the Yongding River is located 982 meters upstream from Lugou Bridge,spanning the Yongding River.This hub was completed and put into operation in 1987 and has been in operation for nearly 40 years.It is a key part of the Yongding River flood control system and a national-level flood control priority project.During the process of reinforcing and eliminating hidden risks of the flood diversion hub,epoxy coatings were used as repair and anti-carbonation materials for the concrete structure.The treated hydraulic structures show good quality,effectively slowing down the carbonation rate of the concrete structure.This paper introduces the epoxy coating repair construction process and relevant technical parameters using the reinforcement and risk elimination project of the Lugou Bridge flood diversion hub on the Yongding River as a case study,which can serve as a reference for similar projects in the future.

Abstract:The Shishan North Park Industrial Zone in Foshan City is significantly affected by frequent heavy rainfall,inadequate drainage systems,and low-lying terrain in some areas,resulting in prominent waterlogging problems.By analyzing the current situation and causes of waterlogging accumulation in the industrial zone,this paper proposes comprehensive treatment measures including source reduction,drainage system optimization,and flood control and waterlogging prevention capacity enhancement,and evaluates the implementation effects of the treatment projects.The results show that after comprehensive treatment,the waterlogging problem in the industrial zone has been alleviated.The research results can provide reference for waterlogging treatment in similar areas.

Abstract:Wu'an City,located on the eastern foothills of the Taihang Mountains in Hebei Province,has a complex terrain and experiences concentrated summer rainfall,making it prone to extreme flooding.Therefore,conducting flood disaster analysis is essential for flood control safety.This paper takes Huoshui Township in Wu'an City as the study area,and through designing rainstorm flood calculations,evaluating current flood control capacity,and analyzing warning indicators,systematically analyzes and quantifies the disaster risk and flood control capacity of four typical villages.The results show that Huoshui Village,where three rivers converge,forms a flood peak gathering point,with a 100-year return period flood peak flow of 824 m³/s.Its flood control capacity is the weakest,significantly lower than that of other villages.The warning indicators show that soil moisture significantly affects the critical rainfall,with Huoshui Village requiring a higher critical rainfall due to its large drainage area,while Baiwangzhuang,due to its small watershed area and large terrain drop,is most sensitive to rainfall.The research results provide technical support and references for refining flood disaster prevention plans for Wu'an City and other mountainous counties.

Abstract:In recent years,clean energy industries such as wind power and photovoltaic power generation in Chengde City have developed rapidly.However,the accompanying problems of soil and water conservation and ecological disturbance caused by project construction have gradually emerged,exacerbating regional soil erosion to a certain extent.Taking the entire area of Chengde City as the research object,the study area is divided into Bashang Plateau,Jieba Mountainous Area,and Yanshan Mountainous Area.Through investigating representative clean energy projects,the characteristics of soil erosion and ecological restoration status during construction and after completion in different regions are summarized.On this basis,targeted management countermeasures and treatment measures are proposed,which can provide reference for soil erosion prevention and regional ecological restoration in similar clean energy project construction.

Abstract:To address the inefficiencies of traditional water conservancy construction supervision models,including delayed information transmission and difficulties in multi-department coordination,an intelligent construction site platform was developed based on technologies such as artificial intelligence,geographic information systems,big data,and the Internet of Things.The platform includes core functional modules such as video surveillance,dust monitoring,personnel attendance,and inspection and testing.It enables intelligent recognition of construction activities,real-time monitoring of environmental parameters,dynamic management of on-site personnel,and full-process traceability of inspection and testing.Research shows that the application of the intelligent construction site platform has realized visual monitoring of the entire construction process,intelligent risk early warning,and dynamic multi-party coordination management,enhancing the ability to identify quality and safety hazards and effectively controlling construction schedule deviations.It provides intelligent and refined management methods for water conservancy project construction.

Abstract:Kenli District is a region severely lacking in water resources.To effectively alleviate the water supply-demand contradiction in the district,the No.4 Reservoir is planned to be utilized for water storage and regulation,with an expansion of its capacity.The analysis and calculations cover aspects such as the water supply range,supply targets,water demand in the project area,available water supply,and water volume regulation,leading to the determination of the capacity expansion for the No.4 Reservoir.The total reservoir capacity is 4.07 million m3,with a dead storage capacity of 500,000 m3,a usable storage capacity of 3.56 million m3,and an outflow of 3.2 million m3.The research results provide a basis for the scale of the No.4 Reservoir capacity expansion project in Kenli District and offer a reference for similar capacity expansion projects in irrigation and water supply scale analysis.

Abstract:River health evaluation is an important foundation for comprehensively promoting the construction of happy rivers and lakes.Taking the Jiayi River in Luoding City,Guangdong Province as an example,this paper constructs a mountain river health evaluation system with"basin""water""biology"and"social service function"as the criterion layers,and evaluates the health status of the Jiayi River.The results show that the score of the"basin"criterion layer is 88.42,the"water"criterion layer is 82.83,the"biology"criterion layer is 81.60,the"social service function"criterion layer is 83.26,and the comprehensive evaluation score is 84.13.According to the river and lake health evaluation standard classification,the Jiayi River belongs to Class II rivers and lakes.On this basis,the scoring results of each indicator under"basin""water""biology"and"social service function"are further analyzed,the main existing problems of the Jiayi River at the current stage are sorted out,and corresponding countermeasures are proposed.

Abstract:This paper systematically summarizes the main design points of the main water conveyance canal of the Xixiayuan Water Conservancy Hub,including the determination of channel cross-sectional form and dimensions,the arrangement of slope lining and jointing structures,and the determination of canal crest elevation based on hydraulic calculations.A typical unfavorable section is selected to carry out anti-sliding and anti-seepage stability analysis of the canal,so as to verify the rationality of the design scheme.On this basis,through anti-freezing design and protective measures for locally special canal sections,the service life and durability of the canal are further improved.The results show that the designed section meets relevant code requirements under different working conditions,which can provide assurance for the safe and stable operation of the project in the later stage.The research results are of great significance for improving regional water resources allocation efficiency,ensuring food security,and perfecting the modern water network system.

Abstract:River-crossing bridges are an important component of urban infrastructure,playing a significant role in strengthening regional connectivity and promoting integrated transportation development.River-crossing bridge construction is closely related to river flood control safety.With the acceleration of urbanization and the increase in extreme climate events,the flood control impact issues of river-crossing bridge engineering have become increasingly prominent.Addressing the impact of river-crossing bridge construction on flood conveyance safety,river regime stability,and levee safety,this paper takes the Dahewan Huaihe River Bridge in Bengbu City as the research object,proposes corresponding compensation measures to mitigate the adverse effects of bridge construction on the river channel and levees.The research results can provide reference for river-crossing bridge engineering.

Abstract:As a critical drinking water source for Tianjin and Tangshan cities,Panda Reservoir was investigated to accurately understand the phytoplankton community structure,spatiotemporal distribution,and current aquatic ecological status,and to clarify water nutritional state and algal bloom risk.From May to October annually(with intensified monitoring during the August cyanobacteria high-incidence period),10 sampling sections were established in the reservoir area for qualitative and quantitative phytoplankton surveys,with multiple water environmental parameters measured synchronously.A total of more than 128 species belonging to 8 phyla were identified,with Cyanophyta showing the highest proportion in community composition;Pseudanabaena,Scenedesmus,and Chlamydomonas were determined as the dominant species.The phytoplankton in the reservoir area exhibited obvious seasonal succession characteristics,and the water body was classified as cyanobacteria-diatom type.Water quality evaluation results indicate that the reservoir water quality was rated as Class II,meeting or exceeding Class III water standards;although slight algal bloom risk existed in local waters,the cyanobacteria outbreak trend had been effectively curbed.This study provides basic data and scientific basis for aquatic ecological monitoring,water source protection,and algal risk prevention and control in the reservoir area.

Abstract:Shandong Province currently has 5,241 small reservoirs,mostly distributed in hilly areas.Once a major danger situation that may cause dam break occurs,insufficient preparation,inadequate measures,and untimely emergency rescue will seriously threaten the lives and property of downstream people.To analyze the impact of dam-break floods from small reservoirs in hilly areas,this paper takes the Sanba Reservoir in Zouping,Binzhou as an example,constructs a two-dimensional dam-break flood numerical simulation model,simulates the flood evolution process under the condition of over-standard flood overtopping and instantaneous dam break,analyzes the impact of dam-break floods at different moments on downstream commercial areas,residential areas,and major infrastructure,and calculates the inundation area,flow velocity,and peak arrival time of the dam-break flood.The research results can provide reference for flood control project construction and non-engineering measure management,facilitate maximizing the comprehensive benefits of flood control projects and hold primary significance for flood control and disaster mitigation.

Abstract:Aiming at the characteristics of small and medium rivers,including strong flood suddenness,short confluence time,and great difficulty in forecast and early warning,this paper explores rapid forecast and early warning methods for small and medium river floods.Taking a hydrological station in Zhejiang Province as an example,historical flood process data of the basin are collected,and regression analysis is used to analyze the correlation between peak-generating rainfall,rainfall duration,and water level rise,constructing a forecast water level quick-reference table based on a linear regression model.Meanwhile,the upstream-downstream water level correlation method is used,combined with mathematical function relationships,to rapidly derive the peak water level at downstream hydrological stations.The research results can provide reference for defense dispatch of small and medium river floods.

Abstract:Aiming at the common problem of coordination between water supply and ecology faced by reservoir ecological water replenishment in humid southern regions,this paper takes Jiaohua Reservoir as the research object and constructs a multi-scenario regulation model.The coupled effects of initial water level,replenishment start month,and ecological replenishment volume on water supply guarantee and ecological benefits are systematically analyzed,with the objective of identifying the optimal regulation strategy under the constraint of water supply satisfaction rate≥95%.The results indicate that 155 m is the effective implementation threshold for ecological water replenishment,175 m is the full-strategy water supply security threshold,and the period from February to April constitutes the optimal replenishment window,with March yielding the best comprehensive benefits.Based on the initial water level,three stages of high,medium,and low are divided,and a differentiated dynamic regulation scheme is proposed.A coupled regulation model of ecological replenishment volume,replenishment start month,and minimum initial storage capacity is established.The phased dynamic regulation strategy proposed in this study achieves a balance between water supply safety and ecological benefits,providing technical support for ecological regulation of similar reservoirs in the Xiangjiang River basin.