Division of Water Environment aims to develop into an international forefront in water technology and to address many of China's urgent water pollution control and environmental protection issues of today. Through the integration of advanced technologies including modern biotechnology, chemical and information technologies, as well as developing and devising new materials, the researchers in Division of Water Environment conduct a variety of research directions involving advanced industrial wastewater treatment and urban sewage purification, novel theories and technologies for resource and energy recovery from wastewater, monitoring and mathematical simulation in water pollution control processes, and water reclamation technologies and theories.

The Division of Water Supply and Drainage (DWSD) focuses on the major national requirements and the frontiers of international scientific issues such as urban and rural municipal water infrastructures, urban water safety, and future urban water systems, and aims to advance the fundamental research, technology innovation, and social service involved in different fields, e.g., drinking water safety, water pollution control, and urban water infrastructures sustainability. Additionally, DWSD carries out the teaching and education activities in water supply and drainage fields, and is to cultivate undergraduate and graduate students with excellent international vision, industrial experience, and academic training.

The key research interests of DWSD include: 

(1) theories and technologies development in drinking water safety and health risk control;

(2) innovation in physicochemical and biological treatment technologies; 

(3) optimization and intellectualization of municipal and indoor water pipeline systems; 

(4) water quality improvement and water ecology in urban rivers and lakes; (5) resilient urban green water infrastructures and future urban water systems.

The research results are expected to provide important theoretical, technical, and management support for continuously improving the planning, design and operation of urban and rural water infrastructures, ensuring urban water safety and leading the construction of future urban water systems. Finally, DWSD strives to achieve implementation and industrialization of innovative technologies and provide technical services to governments, enterprise and social institutes.

Division of Soil and Groundwater Environment aims at the national strategic needs and the cutting-edge international research on soil and groundwater environment. With faculties of multidisciplinary background, the division conducts original and strategic research in theory and technology of soil and groundwater pollution control and remediation, risk assessment and management, safe utilization of soil and water resources, etc. Researchers strive to reveal the process and mechanism of soil and groundwater pollution, identify spatial and temporal variation of soil microbial community structure and functions with global change, develop the theory, technologies, materials and equipment for green and sustainable pollution prevention and remediation, establish methodology of related ecotoxicity and risk assessment, and draft the technological standards and specifications for assessment and remediation on contaminated sites. The research outcomes and findings have provided strong support to the scientific decision-making and promoted the improvement of soil and groundwater environmental quality via multidisciplinary effort in China.

The research of air pollution control seeks to solve urgent air pollution problems in China while keeping up with international research frontiers. It has carried out highlevel scientific research on the formation and emission of air pollutants, atmospheric transport and physicchemical processes of air pollution, simulation of air quality, and air pollution control technologies, strategies and countermeasures. It has been long engaged in the multi-scale research of new sciences and technologies of air pollution control, and assisted major national strategic decision making. The division of air pollution control has successfully completed a number of significant national research projects. The division has become a major force in the field of air pollution control and an important base for talent cultivation.

As a multidisciplinary research field integrating scientific research, engineering, and management services, the research of solid waste management and recycling is supported by new materials science, thermodynamics, microbiology, engineering chemistry, modern computational mathematics, and advanced management science. The main research areas include:

(1) Environment-friendly solid waste treatment and environmentally safe treatment of hazardous waste

(2) Resource technology for solid waste and biomass waste

(3) Remediation of sites contaminated by solid waste and hazardous waste

(4) Sustainable solid waste management and risk control.

A number of engineering centers and joint research centers have been set up at SOE, including the UNEP Basel Conventional Coordination Center for Asia and the Pacific and UNEP Stockholm Conventional Regional Center for Capacity-building and the Transfer of Technology in Asia and the Pacific.

Division of Environmental Chemistry manages to illustrate the chemical mechanism which leads to the occurrence and evolution of environmental problems, and to find appropriate chemical methods, technologies and advanced materials to prevent and control the environmental pollution. is devoted to approaching environmental problems from the chemistry perspective and solving regional and global environmental problems by using chemical and material methods. The main research fields include:

(1) Environmental pollution chemistry: investigate the analytical methods, pollution characteristics, transportation and transformation of emerging pollutants in multimedia.

(2) Environmental pollution control chemistry and materials: study the technology principles of efficient adsorption, advanced oxidation and reduction for effective removal or degradation of various emerging pollutants, and develop novel materials and equipments.

(3) Environmental risk assessment and control strategy for chemicals: investigate methods to evaluate the eco-environmental safety and measures to implement the Stockholm Convention.

SOE has established POPs Research Center, and Tsinghua Environmental Quality Test Center, which support the teaching, research and social service in the field of environmental chemistry.

The Division of Environmental Biology is dedicated to fundamental and advanced studies on natural eco/biological-system, biological engineering processes for environmental pollution control and bioremediation.

The faculty direct leading-edge research programs across a wide range of new fields:

(1) Exploitation of environmental microorganisms and microbial products for environmental pollution control and bioremediation；

(2) Novel biological technologies for organic pollutants control；

(3) Technology and mechanism for biodegradation and bioremediation of environmental pollutants；

(4) Water resource reclamation and safe reuse；

(5) Toxicity of environmental contaminants and risk assessment.

Environmental ecology mainly focuses on hot issues of the global ecological systems, as well as important environmental science and technology needs in China. Based on the basic principles of ecology and combined with research on environmental science, industrial ecology, ecotoxicology, pollution ecology, landscape science, conservation ecology, systems science and other disciplines, Division of Environmental Ecoology focuses on changes of human activities and their impacts on perturbation mechanism, influence effect and response regulations targeting ecological environment. The main research areas include:

(1) Theory and application of ecological civilization;

(2) Biodiversity conservation and ecosystem changes and monitoring;

(3) Industrial ecology and pollution prevention;

(4) Pollution ecology and ecotoxicology;

(5) Substances metabolism and human circulation science.

Focusing on environmental pollutants, environmental pathogenic microorganisms and the complex relation between human, animal and environmental health,the Division of Environmental Health conducts basic theoretical and key technological research on four major areas: occurrence and formation of environmental pollutants and pathogenic microorganisms in the environment, their migration, transformation or transmission mechanisms, environmental exposure and health risks, and environmental safety and risk control. In this way, it promotes the integrated innovation of environmental science, environmental engineering, and environmental management, cultivates interdisciplinary talents in environmental health, builds a platform for basic environmental health sciences and the cutting-edge technology development, and provides talents and technical support for the construction of the national environmental health governance system and the prevention and control of environmental safety during severe pandemics. Major research directions include:

(1) Screening, identification and toxicity mechanisms of toxic pollutants;

(2) Pollutant exposure science and health risks;

(3) Occurrence and transmission control of pathogenic microorganisms in the environment;

(4) Impact of atmospheric processes on the health effects of pollutants;

(5) Environmental health risk management and control of new pollutants.

Environmental system analysis is oriented to major national environmental decision-making needs, and is committed to basic research and application practice of environmental system assessment, simulation and optimization theoretical methods. The division of Environmental System Analysis has conducted a series of research work in areas such as regional environmental planning, water system planning and management, energy and global climate change, strategic environmental assessment, etc., providing comprehensive solutions to the problems of the social-economic-environmental complex system. The main research directions include:

(1) Water system planning and management, such as sustainable urban water environment system construction theory and methods, urban water system optimization operation and multi-facility coordinated regulation, sponge city construction planning and performance evaluation, etc.;

(2) Energy And global climate change, such as economic-energy-environment system simulation and policy evaluation, global climate change simulation and response, low-carbon transition and carbon neutral technology path, etc.;

(3) strategic environmental assessment, such as national major regional strategic environmental assessment, Industrial development strategy environmental assessment, water-energy-pollutant coupling system simulation and evaluation, etc. Relying on the Institute of Teaching and Research, the Asia-Pacific Water Safety Research Center of Tsinghua University, the Strategic Environmental Assessment Research Center of Tsinghua University and other institutions provide a good hardware and software environment for teaching, scientific research and social services in the field of environmental system analysis.

For the demand of ecological civilization and its supporting environmental governance system cultivation, Division of Environmental Management and Policy dedicates to theoretical innovation, policy measures optimization, management methodologies and tools development and practical application in the fields of environmental policy design & assessment, industrial ecology & circular economy, ecological and environmental big data, and environmental industry to provide scientific management and policy solutions for circular economy, carbon peaking and carbon neutrality, and environmental protection investment and financing, etc. The achievements have been applied to the innovation of decision-making and mechanisms by environmental management departments at all levels of government, the optimization of green development of environmental industries.

Addressing the major national strategic needs to build a beautiful China and achieve the "dual carbon" goals, the Division of Environmental Sustainability comprehensively applies the research thinking and modeling methods of frontier disciplines that value interdisciplinarity such as systems engineering, sustainability science, and complex systems science to study the interaction and coupling between human economic and social activities and the ecological environment from a holistic system perspective. It is committed to uncovering the complex interaction mechanism between human economic and social activities and the ecological environment; analyzing the safe and stable operating laws of environmental-economic-social complex systems at different scales; developing new models and tools for comprehensive analysis and management of complex systems; providing leading theories, methods and technical support for ecological environmental protection under the vision of sustainable development. Major research directions include:

(1) Study of the comprehensive economic and social metabolism process across sectors, including the spatiotemporal evolution of material and energy metabolism, the scientific laws of economic and social metabolism processes and their driving mechanisms.

(2) The theory and method of whole-process assessment of environmental impacts based on the whole life cycle concept: conducting research on the systematic assessment and control of ecological environmental impacts supporting sustainable development goals, and promoting the establishment of technical paths and management mechanisms for the accounting and realization of ecological product values.

(3) Conducting research on the analysis and optimal regulation of economic-social-environmental complex systems with multi-factor coupling, including analyzing the complex mechanisms and regulatory strategies of water-energy coupling, food-energy-water coupling, etc., and carrying out coordinated optimization of carbon and pollution.

(4) Designing production process based on ecological environment constraints and sustainable goals concepts, constructing ecological design principles and methods based on the harmonious coexistence of humans and nature, establishing assessment methods for carbon footprints and environmental footprints that connect multiple scales, and exploring technical paths and key strategies for industrial symbiosis.

(5) Based on scenario simulation and multi-objective optimal regulation research, conducting multi-dimensional comprehensive cross-sectoral and cross-media analysis of material stocks and flows, and establishing sustainable management policies that coordinate economic and social development and ecological environmental protection. It gives full play to the advantages of interdisciplinary integration and comprehensively applies frontier methods to lead ecological environmental management and sustainable development practices, providing scientific and technological support for promoting green and low-carbon transformation, achieving coordinated reduction of pollution and carbon emissions, and promoting the construction of ecological civilization.

Center for Water and Ecology, Tsinghua University aims at the international frontiers and national strategic needs, conducts theoretical exploration and technological innovation of water pollution control and water quality safety assurance, and strives to promote and realize the systematic combination of basic research and engineering applications. Key research directions include:

(1) Relationship and regulation of water quality and water ecology, focusing on the ecological response to changes in water quality and the ecotoxicological effects of trace pollutants, starting from the microscopic research of chemistry and microorganisms; focusing on the development of new methods, new chemicals, new equipment, and new processes for water ecological restoration and sustainable conservation.

(2) Safety guarantee of drinking water quality, including the main links of water source water quality assurance, safe preoxidation, conventional enhanced treatment, deep purification and safe transmission and distribution systems, with the core of water quality conversion process and risk control, to develop the scientific principles of drinking water safety assurance, and to develop key technologies , to establish an integrated technology system.

(3) The green process of water pollution control, conducting energy flow analysis of materials, and systematically study the energy consumption of material separation and conversion, energy recovery in the water treatment process, conversion of materials into energy, and energy utilization processes.