Urban Water Management for Future Cities

To mitigate the negative impacts of urban stormwater problems related to rapid urbanization in China, a new term “sponge city” was proposed, with related practices and implementation approaches examined in depth. The components and main goals of the sponge city concept and stormwater management criteria were introduced, while the relationship and difference between sponge cities in China and urban stormwater management systems in developed countries were compared and analyzed. Moreover, the policy and regulations that have been released were summarized, and recommendations for the future of sponge city development were provided.

Sponge City development is embedded in a realignment of urban development with a strict focus on water. In recent years, especially China has undertaken many concrete efforts and high investments in order to promote the Sponge City approach and to galvanize the decision makers to action. China aims at shaping water sponging cities to better cope with climate change and to especially mitigate negative impacts of extreme rainfalls on urban spaces. However, the advantages of green and spongy cities only will develop their full potential if operation and maintenance (O&M) are performed adequately and accurately. Especially, maintenance must be seen as a core element of asset management. In the Sponge City case, adapted preventive maintenance strategies should be pursued comprehensively considering the local (climatic) circumstances so that unnecessary performance losses and further negative side effects do not occur in the Sponge City infrastructure. Sufficient financial resources must be available for this task. In order to minimize future efforts and costs, the findings from previous maintenance activities will be crucial for design modifications or adjustments. Maintenance in Sponge City environments stimulates innovation, assures feedback, shows weak points, enhances reliability, and provides reason to improve the entire urban water system (including the underground infrastructure). If the implementation is successful, the Sponge City might be the starting point for further developments that fuel urban transformation.

Current planning situations in Europe and China include upgrading or replacing of existing WWTPs (mainly in Europe) and the construction of new WWTPs (mainly in China). Both planning situations are increasingly confronted with future uncertainties due to high system complexity and rapidly changing conditions. In contrast to this, the long service life of over 30 years and the high capital commitments required lead to entrenched wastewater treatment concepts fixed over decades by the first design decision. In order to complement established WWTP planning methods, a methodology of future-oriented strategic planning focusing on WWTPs is presented in this chapter. The main purpose of this methodology is to define, simulate and evaluate potential long-term technological strategies for a WWTP. The basic steps of the methodology include (i) defining long-term technology concepts and (ii) corresponding transformation paths of a WWTP under different future scenarios. Finally, the methodology allows (iii) an ongoing control of scenario assumptions and (iv) an early support to start adapting the defined long-term technological concepts to current conditions. By this, the methodology will support the finding of robust and economic transformation paths and evaluated construction steps.

The water-energy nexus describes the connection between water and energy. Here we focus on energy for water supply to urban areas of China. Electricity use is one of the main costs for water companies and tends to be the main source of greenhouse gas emissions during water supply. In a country where reducing energy use and emissions is now an important part of the national agenda, managing energy use will become a major focus for the water industry. This chapter provides an overview of energy use at each stage of water supply in China: sourcing and transfer, water treatment, central distribution, and distribution within high-rise buildings. We then focus specifically on water distribution, which is a major energy user, and use statistical data from four cities in China and Japan to draw conclusions on how city layout affects the energy needed to supply water.

The Tai Hu (Tai Lake) is used as a raw water reservoir for approximately ten million inhabitants predominantly in Jiangsu province, China. Algal/cyanobacterial blooms occur frequently in the eutrophic shallow lake and present a challenge for drinking water treatment. Furthermore, occasionally taste and odor (T&O) problems have been reported in drinking water. Due to the impacts of wastewater and surface water runoff, pesticides and emerging pollutants such as pharmaceutical compounds must be considered as well.

In our study, a large spectrum of emerging pollutants was analyzed in the northern part of Tai Hu. In a Zhushan Bay wetland, emerging pollutants such as perfluorooctanoic acid (PFOA) and the pharmaceuticals ibuprofen and diazepam were detected. Additionally, pesticides were present in the lake water in concentrations of 0.1–0.5 μg/L. The occurrence of antibiotic resistances at the microbial level was examined in water and sediment samples. In particular the antibiotic resistance genes sul1 and sul2, which encode for resistance against sulfonamide antibiotics, were detected in all samples. Furthermore, the tetracycline resistance gene tet(C) was detected frequently and tet(B) in 10% of the samples. Also, the genes bla _TEM and ermB were detected in Tai Hu samples encoding for resistances against beta-lactams and macrolides, respectively.

The T&O problems observed in drinking water of the Tai Hu region could not be attributed to the algae burden T&O compounds such as geosmin or 2-MIB. This study demonstrates the effects on the water treatment process caused by high amounts of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). The elevated concentration of organic compounds in raw water results in a short life span of ozone during advanced treatment. In the disinfection process, the remaining nitrogen-containing organic compounds undergo subsequent reactions. In particular, amino acids might trigger the formation of chloramine-type T&O compounds. Amino acids were detected in raw water samples taken at the inlets of the Tai Hu water treatment plants and were shown to be present in fluctuating concentrations. Most probably, lysis of algae cells during drinking water treatment due to oxidation processes such as pre-ozonation results in the release of intracellular compounds and elevated aqueous phase concentrations of DOC and DON (containing proteins, peptides, and amino acids). In laboratory experiments, it was shown that algae could be removed effectively by ultrafiltration, thus proving to be a suitable pretreatment process while avoiding cell disruption and subsequent formation of T&O compounds.

Based on analysis of Tai Hu field samples and laboratory experiments, pilot-scale proof-of-concept studies were developed. Future studies will focus on online monitoring of drinking water treatment performance including the precursors of T&O compounds. Also, the removal of emerging chemical and microbiological pollutants will be emphasized in order to ensure high-quality drinking water.

Maintenance of sewer networks is essential for their efficient and stable operation. Although sewer maintenance is basically the same regardless of network type, the specific situation of a particular network will determine how much and how often maintenance is needed. Therefore, the current state of a particular network must be described in detail to identify deficiencies and formulate targets of sewer maintenance which can be tailored to the network. In this article, we present the status quo of sewer networks and their maintenance in Germany and China and suggest how to maintain sewer networks in a customized way. In particular, we place special emphasis on adapting networks to current policy requirements in China using the concept of “sponge cities (海绵城市)” and the concept of “urban landscapes and ecological restoration (Shuangxiu 城市双修).”

This chapter gives an overview of real-time control (RTC) systems in sewer systems. The first sections introduce some of the fundamental concepts and terms of RTC and give a brief overview of German guideline documents on the design of RTC systems. Subsequent sections then describe a case study in Hildesheim, where a general global control system is implemented in the sewer network.

Wetland restoration efforts are increasing due to loss and degradation of many natural wetlands. Eco-cities’ harmony with nature is considered an essential goal for sustainable development worldwide. Among different methods for wetland restoration, the ‘near-natural’ method of ecological restoration has been widely proven to be an effective and practical method for eco-city construction. The development history of the near-natural method is here reviewed, and the nature and properties of the near-natural method are summarized. The differences between the near-natural method and constructed wetland method are analysed, while the phenomena and origin of pseudo-ecological engineering are presented. Finally, Zhushanhu wetland ecological restoration is used as an example to illustrate the design process of the near-natural method, and the ecological restoration results have shown that this method is more effective, sustainable and longer lasting than other methods and thus a practical prospect.

Today’s cities face the challenge of climate change adaptation worldwide. In this context, prevention of damage caused by flash floods plays an important role. This requires a cooperative pluvial flood risk management approach, which includes planning, technical, and administrative measures and involves preliminary flood risk analyses. This article outlines the main components of this risk management approach, which has proven its effectiveness in Europe. The recommendations formulated for this purpose are applicable or adaptable to regions with other constraints, such as China, for example.

With urbanization in China, the sewer system is increasing in scope, and as a result sewer pipe defects have appeared frequently and caused problems. For example, sewer pipe defects lead to the leakage of wastewater, which may pollute groundwater in northern China. On the other hand, underground water may flow into the sewer pipes in southern China as the underground water level is higher than the sewer pipe (unlike in northern China), which dilutes the inlet wastewater in terms of COD to the wastewater treatment plant, reducing the treatment and operating efficiency. As some large cities in China are gradually being equipped with CCTV devices, the demand for an evaluation method usable by Chinese operators is urgent. Therefore, an objective and comprehensive evaluation system should be established to avoid defects and provides real-time practical suggestions under the current conditions of China. Fuzzy mathematic methods in sewer condition evaluation were utilized to decrease the uncertainty during the evaluation process in some studies, but the reliabilities of the evaluations varied based on different fuzzy methods chosen. Thus, fuzzy mathematic methods were introduced in the whole process of evaluation to eliminate artificial errors and give more objective assessment results. A novel comprehensive sewer condition assessment method was also established.

An orderly wastewater disposal and associated wastewater management are important factors for human health and environmental protection. After a brief description of the development and the current situation of wastewater disposal in China, recommendations are given for future activities. The identified deficits in the operation and maintenance of the sewerage systems are currently a special focus of Chinese wastewater management. In many cities the reduction of external water also plays a role. Other areas of work will include measures for industrial wastewater, wastewater in rural areas, and, in the sense of “sponge city,” a different handling of rainwater in urban areas. The “smart cities” targeted in China will also be linked to changes in the conventional centralized wastewater disposal system. In addition, the reinforcement of wastewater recycling has a special significance.

Urban water systems will not be developed and managed in a sustainable way unless this is ensured through adequate regulation, organization, and finance, or in short “governance.” The following sections of this volume aim to explore the different government arrangements in China and in Germany with a view to identifying options for improvement and governance innovation in and beyond these countries. The present chapter is aimed at providing some groundwork for this comparative assessment including an overview of the major factual challenges and differences of urban water governance in China and Germany, a conceptual frame for comparative assessment, a synthesis of the key benchmarks of “good” and “sustainable” governance, and a brief outlook to the highlights presented in the following contributions.

This article reflects the past years of Sino-German cooperation in water governance. Starting with the challenging task of goal setting, both China and Europe have developed toward a holistic understanding of sustainability by setting emission-immission values, taking resilience into account and introducing bioindicators into legislation. Chinese traditions in health-conscious behavior as well as its new concept of “Beautiful China” link to European efforts of revitalizing rivers also for human health and recreation. Secondly, functional administrative structures are fundamental for legal implementation. Integrality and subsidiarity need to be taken absolutely seriously as decisive factors for success. In European countries it has been proven advantageous that only 1 ministry is primarily responsible for water resource management, whereas China manages its water resources jointly by up to 12 different ministries. As this basic structure remains the same from the national level down to the provinces, it guarantees a more similar overall framework than is the case in most European countries. Thirdly, two innovative tools are introduced that allow a holistic comparison, visualization, and evaluation of different water governance systems: within a comprehensive 3D process, model interactions between different stakeholders are represented. A universal indicator system for water governance is able to obtain measurable values to gauge internal performance of a specific water sector. Lastly, urban systems are chosen to exemplify application considerations.

To counter its high urban pluvial flood vulnerability, China has been promoting Sponge City Development, a critical urban transition that requires cross-boundary evolution, particularly among the urban planning and urban drainage sectors. This article analyzes the relevant causes of high urban pluvial flood vulnerabilities in Chinese cities and the enormous gaps between the status quo and the ambitious targets. To bridge the gaps, a three-tier solution system is proposed and is supported by a broad range of approaches, know-how, techniques, examples, concepts, and policies. Firstly, water-sensitive urban planning can minimize macroscale damage on the local hydrological cycle. For example, it is illustrated here how cities can preserve critical ecological infrastructure effectively while developing resiliently, compactly, and habitably, for example, through spatial development criteria, urban growth boundaries and multifunctional urban poly-centers. Furthermore, implementations of low-impact development (LID) facilities can ameliorate local hydrology and reduce runoff pollution. This research thoroughly analyzes the relevant risks and challenges while customizing solutions, e.g., LID planning, based on improved hydrology – hydraulic and water quality simulations, management train, and separated treatment. Lastly, urban sewer system can be improved cost-efficiently via improving top-level designs and also via fully releasing, utilizing, and activating the existing sewer system’s drainage and detention potential. Although the lessons and recommendations reviewed here are customized for Chinese cities, they can also be a reference for other fast-developing cities endangered by urban pluvial flooding.

China has serious problems in urban water resource management, which have profound social, economic, and political implications in China. It is necessary to analyze political and governmental policies, legal rules, technical standards, authorities and responsibilities of governmental agencies, and other issues related to the urban water resource management. The constitutional basis for urban water management mainly lies in the ownership and the division of governmental powers. The CPC and the legislative bodies, executive bodies, and judicial bodies of the government all have authorities and make rules for urban water management. Rules may take the form of national or local legislation, administrative regulations or rules, or technical standards. Relevant regulatory agencies mainly include the Ministry of Ecology and Environment, the Ministry of Water Resources, and similar local agencies. Planning and functional zoning, administrative permits, and technical standards are key regulatory tools for urban water management. The CPC and the government have adopted some important measures to improve urban water management.

This contribution depicts the governance arrangements for water resource management in the regions of the Tai Lake Basin and in the city of Wuhan. As to the Tai Lake Basin, the focus is on pollution control. It is shown that sustainable, integrated water management is strongly impeded by high fragmentation of the administrative competences and that adequate organizational integration and effective coordination instruments are lacking. The city of Wuhan is presented as an advanced example regarding the implementation of the “Sponge City” concept. It is shown that Wuhan has managed to establish a more integrated administrative arrangement for the purpose of water infrastructure development and a complex structure of objectives, standards, and responsibilities for the advancement of the Sponge City project. In order to place these examples of regional water governance into the wider national picture, we firstly provide a brief overview of the factual and institutional backdrop in China.

This contribution provides an overview about the German water protection law and about the legal strategies and instruments for water management. The analysis also includes the legal European approaches to water management and their relevance for the German legislation. The report emphasises the legal framework for waste water disposal which is laying down in federal and Länder law.

Water governance across Europe is mainly affected by the European Union Water Framework Directive 2000/60/EC (WFD), the key legislative instrument to protect and manage European water resources. The WFD requires EU member states to produce and implement river basin management plans, which are to be designed and updated via participatory processes. According to Article 14 WFD, all interested stakeholders shall be actively involved in order to push the effectiveness of the environmental impact of the WFD. However, 18 years after the WFD’s entry into force, 50% of EU waters are still lagging behind the “good status” objective of the Directive. Therefore, implementation shortcomings call for a greater focus on the principles of good water governance, which shall apply to water-related policy areas such as agriculture as well. Ensuring availability and sustainable management of water and sanitation for all is a necessary condition for ending poverty and hunger, improving quality of life and achieving most of the other ambitious goals proposed in the 2030 UN Agenda for Sustainable Development, especially goal 6 (clean water and sanitation).

In order to control water pollution of Tai Lake Basin, the Chinese government has implemented a series of economic, technological, and industrial policies during the past decades. This study aims to present the achievements and challenges of water pollution control in the Tai Lake Basin, focusing on the economic policies, such as pollution levy, green credit, ecological compensation, compensated use of pollution discharge rights and pollution discharge rights trading, and environmental pollution liability insurance. The results of this study indicate that China has made great progress of policy design and implementation, especially in Tai Lake Basin. These policies have prevented the deterioration of water quality in Tai Lake. At the same time, further improvements of their implementation are still needed in the future.

An earlier version of this chapter was published as “Dai L (2014) Exploring China’s approach to implementing ‘eco-compensation’ schemes: The Lake Tai watershed as case study considered through a legal lens. Water Int 39(5):755–773.” Copyright © International Water Resources Association, reprinted by permission of Taylor & Francis Ltd., www.tandfonline.com on behalf of International Water Resources Association.

Tai Lake is the third largest freshwater lake in China. Serious water pollution, especially trans-jurisdictional water pollution, problems are consistent issues in the region. To deal with these problems, four types of the eco-compensation mechanism are applied in this region: eco-compensation between governments, eco-compensation between governments and farmers, eco-compensation between governments and industry and eco-compensation among industries. This chapter analyses these four types of the eco-compensation mechanism from a legal perspective and sheds light on how the mechanism has been applied in China. It aims to provide valuable experiences for domestic water management and elsewhere in the world in protecting the provision of water-related ecosystem services.

Sustainable water management is still one of the major challenges of our times, and economic instruments may significantly contribute to a transition towards sustainability in water management. This chapter provides an overview on the current state of the implementation of sustainable water management in Germany. After introducing environmental policy instruments with a special focus on water pricing, the chapter gives an overview of topical challenges in Germany by looking in particular at the design of key policy instruments and the related need for reforms. The following points will be taken into consideration: contradictory requirements of water pricing, deficiencies of current tariffs against the background of changing demand structures, the role of environmental regulatory charges and the importance of a pending urban water sector transition. It will be shown that Germany’s water management is far from being completely “sustainable” – despite all the successes achieved to date.

The full cost of urban water use is all the cost paid directly or indirectly by urban society based on market price. According to the life cycle of urban water use, full cost can be divided into five parts: water intake cost, water making cost, water supply cost, water draining cost, and sewage treatment cost. In this study, an accounting method is constructed for calculating full cost of urban water use, and it has been proved reasonable and feasible. The case study of city A shows that city A’s full cost of urban water use reaches 6.23 Yuan/ton at least, while local domestic water price is only 2.05 Yuan/ton, which obviously does not cover full cost urban society pay for water use and undoubtedly cannot reflect the real value of urban water resource. It is suggested that water price should be made based on full cost so that the cost of urban water use could be explicit; thus, water price policy can play a more effective role in water resource allocation. Besides, full cost of urban water use accounting can effectively promote popularization and application of private-public partnership (PPP) mode in the field of water service. Lastly, it is necessary to improve information disclosure of full cost of urban water use to realize scientific and democratic management.

Assessing the economic impacts of flooding is a crucial part of identifying appropriate flood risk management options as required by the EU flood management directive. This chapter describes methods for assessing economic flood damage. To begin, some fundamental issues are discussed: Which types of economic flood damage should be taken into account? What kind of information is necessary in general for assessing flood damage in monetary terms, and what is the general procedure for calculating economic flood damage? Having clarified these questions, the methodological challenges posed by economic flood risk management are described. This includes the indirect impacts, i.e. induced loss to customers and suppliers of good and services damaged by floods, and intangible impacts, i.e. the impacts of flooding on mortality and morbidity and the environment. Ways to deal with the persistent uncertainty in damage and risk assessments are discussed in the following chapter. The findings in this chapter will be evaluated in relation to flood risk management practices in Germany, based on examples from Saxony.