The theme of the 32nd World Water Day in 2024 is "Promoting Peace with Water", and the 37th China Water Week, which is also held at the same time, is "Using Water Resources with Meticulousness and Strictly Managing Water Resources". This demonstrates the strategic role of water resources in promoting sustainable economic and social development in China.
Leakage of the urban public water supply system pipeline network not only causes waste and pollution of water resources, but also directly affects the health and safety of residents in water use. On a global scale, major cities are actively controlling the leakage of urban public water supply networks, and the level of leakage treatment and control is constantly improving. Asian countries such as Japan and Singapore, due to their small regional scale and appropriate leakage control measures, have maintained a leakage rate of 3% -4% in recent years. Some cities in Europe and other countries have a long history of pipeline networks, and with efforts, the leakage rate is controlled between 5% -35%.
China's management of water resources is also continuously becoming stricter, and the requirements for the leakage rate of water supply networks are constantly increasing. From the target of 10% proposed in 2015 to the goal of controlling the leakage rate within 9% by 2025 proposed in 2022. According to the "China Urban and Rural Construction Statistical Yearbook" (2021), the comprehensive leakage rate of public water supply in cities and county towns in China was 12.68% in 2021, which still falls short of expectations.
Reducing water supply network leakage is a long-term and arduous task in urban water supply construction and management. At the same time, addressing leakage is a complex system engineering that involves facility updates, zoning measurement, water supply optimization and scheduling, water supply intelligence, and institutional mechanism innovation and optimization. In the practice of leakage management and control in water supply enterprises, effectively improving the stability and safety of pipeline network operation, optimizing the water quality, measurement, and quantity of people's water use, greatly improving the quality of water use for residents, is the process of comprehensively improving the level of urban water supply and people's livelihood services in China.
01 Carry out leakage control and systematically improve the level of urban water supply
The urban water supply network is a very large underground connector, and leakage problems may occur in various links, such as municipal transmission and distribution networks, secondary water supply systems in residential areas, and measuring instruments. There are various complex factors that cannot be predicted or even controlled. In addition, pipeline leakage is generally difficult to detect, and the consequences are very serious. Therefore, for most water supply enterprises, the governance and control of pipeline leakage has always been a thorny problem.
Although the work of water supply leak detection was carried out early in our country and the methods of management and maintenance are constantly developing, in the past when technology was lacking, to find these leakage points underground, we can only rely on experienced leak inspectors to walk with both feet and ears. With the continuous development of information technology in recent years, water supply enterprises have utilized information technology and data processing methods for pipeline management, especially with the development of big data, Internet of Things and other technologies. Water supply enterprises have combined leak control management with smart water management platforms to achieve comprehensive optimization of water supply quality.
Water supply services are a work that is tailored to local conditions, and water supply enterprises in different regions have formed different practices based on their actual local conditions. In 2023, the Ministry of Housing and Urban Rural Development released a replicable policy mechanism list for urban public water supply network leakage control, introducing some regional experience and achievements in leakage control, such as promoting the renovation of old water supply networks, establishing a sound water use zoning measurement system, and intelligent construction of water supply networks.
In terms of updating and renovating old water supply networks, due to the long service time of the network, complex pipes, and outdated water supply infrastructure, leakage problems are more concentrated in old residential areas, which can easily cause unstable water quality and pressure for a few residents. Therefore, the water supply renovation of old residential areas is not only the foundation of urban leakage control, but also an important work to improve the quality of water use for residents. In recent years, China has continuously accelerated the renovation of urban shantytowns and dangerous houses, and promoted the renovation of old residential areas. During the process, water supply enterprises also actively updated and upgraded the pipeline network and facilities of old residential areas, and improved and enhanced the water quality of the communities.
For example, it is mentioned in the list that the water supply departments of Tangshan City in Hebei Province and Fujin City in Heilongjiang Province have simultaneously implemented household water meter renovation, pipeline network renovation, and old municipal water supply pipeline renovation in the renovation project of old residential areas. This has effectively solved the problems of unstable water quality and insufficient water pressure in some old residential areas while reducing pipeline leakage; Lichuan City, Hubei Province conducts a comprehensive evaluation of the water supply network situation, continuously formulates and organizes the implementation of renovation plans for old pipelines every year, and continuously ensures the safety of urban water supply and the improvement of water supply quality in leakage control and management.
In establishing a sound water use zoning and metering system. Partition metering management refers to dividing the entire urban public water supply network into several water supply areas, monitoring and analyzing the flow changes in each partition, evaluating pipeline leakage, and providing timely feedback. It is an important means of leakage control. Zoning measurement requires a comprehensive survey and evaluation of the pipeline network within the water supply range, and the installation of node flow meters as a hardware foundation. After implementing zoning measurement, the water company can more accurately carry out pipeline maintenance and services based on the leakage water volume and distribution in different areas.
In 2019, the water supply department of Wuxi City, Jiangsu Province launched a water management system for zoning and measurement. The installation of remote flow meters in pipelines and the construction of community DMA (adding high-precision electronic remote water meters) provide a scientific basis for leakage control. In 2021, the leakage rate of Wuxi pipeline network was 9.3%, and in 2022 it was 8.2%, achieving a continuous decrease in leakage rate.
On the basis of the established three-level measurement zoning system, Fuzhou Municipal Water Supply Co., Ltd. has further adopted a more refined elastic zoning management. based on the leakage assessment results and leakage control situation between the secondary zoning and the community DMA, a flexible measurement zoning with adjustable boundaries, controllable scope, and regional grid can be established, forming a two-way feedback mechanism for measurement zoning and leakage control. Combined with the zoning policy of leakage control, it effectively reduces construction costs and management and maintenance costs. Combined with measures such as renovation and replacement, the treatment effect is obvious, and the leakage rate has decreased from 25.7% in 2017 to 5.3% in 2023.
In terms of intelligent construction of water supply networks, digital development has become a new driving force for various industries in recent years, and the value of data resources in the water supply industry has also been realized. In terms of leakage control of water supply networks, many effective management systems and solutions have been developed. At the same time, water supply enterprises can also use intelligent construction to achieve fine control of the entire water supply process, such as water quantity scheduling, water pollution emergency, and emergency response to sudden accidents. This not only achieves important breakthroughs in leakage control, but also greatly improves the quality of water safety.
02 Funding source is a challenge, hindering the process of leakage control
At present, national policies have clearly defined the requirements for improving the overall level of leakage control, and various regions are still accumulating experience. Under the gap with the goal, some problems are also exposed.
There is a high demand for renovation funds. Due to the weak foundation, the treatment of water supply network leakage usually requires the updating and renovation of infrastructure, equipment, and instruments, with a large one-time investment. According to the calculation of E20 Water Supply Research Center, the total funding demand for the renovation of water supply networks in China during the 14th Five Year Plan period is approximately 150 billion yuan, which is allocated to 30 billion yuan annually.
The source of funds needs to be strengthened and guaranteed. Although some pilot projects are proposed to be appropriately supported by central budget funds in the leakage control policies issued by the country, a research report on the application and development trend of municipal water supply industry pipes (2021) released by the E20 Water Supply Research Center indicates that the funds for pipeline network renewal and renovation have always been borne by water supply enterprises, and only in a few cases will the government make contributions.
As the main operating entity for long-term pipeline protection, water supply enterprises have a leakage rate that is related to national level assessment and business indicators. Faced with the characteristics of large investment in leakage control and long capital cycles, relying solely on water supply enterprises will inevitably exacerbate water price inversion in the long run, which is not conducive to the quality improvement and healthy development of residential water use.
Industry professionals in the water supply industry have stated that in response to funding difficulties, water supply enterprises should continue to promote renovation and maintenance, continuously improve water supply quality, and mainly rely on increasing water fee income and obtaining external financial support. The newly introduced water supply pricing policy in 2021 has strengthened the connection between leakage rate and water prices. The part with a leakage rate exceeding 10% is the extra cost borne by the water supply enterprise and cannot be solved by adjusting the water price. Leakage management will inevitably become a long-term and arduous task for water supply enterprises. Water supply enterprises must innovate and optimize the effectiveness of leakage management on the basis of guarantee.
The leakage rate in this city has reached 6%, and the water supply service has achieved "5A"
The built-up area of Fuzhou has a long history, and water supply construction started in the 1950s. Due to the limitations of construction technology conditions and the development of materials and equipment technology at that time, many municipal pipelines and water supply systems in old residential areas are already overwhelmed, and the situation of pipeline leakage is becoming increasingly serious.
As early as 2009, Fuzhou Municipal Water Supply Co., Ltd. began receiving water supply from residential areas within the scope of the current situation in accordance with the guidance of the Municipal Party Committee and Government in serving the people's livelihood. It implemented the working principle of "meter reading to households and service to terminals", and changed the billing method from general meter billing to charging to end users. Internal leakage in the residential areas was also borne by the water supply enterprise. In 2011, Fuzhou became one of the first provincial capital cities in China to comprehensively collect household data, while being affected by old residential areas. In 2012, the leakage rate of the water supply network in Fuzhou also reached a historical high of 42%. Fuzhou Water Supply Co., Ltd. quickly carried out leakage control work on the water supply network, continuously carrying out a grid like investigation of underground pipelines, transforming and replacing mismatched and over aged pipelines, improving the operation status of the water supply network, and laying a good foundation for subsequent work. After years of governance, the leakage rate of the water supply network in Fuzhou has been decreasing year by year, from 25.7% in 2017 to 5.3% in 2023. The speed and effectiveness of leakage control are obvious.
In terms of management, Fuzhou Municipal Water Supply Co., Ltd. has always actively promoted the management of public water supply network leakage, continuously optimized the scientific and reasonable management system and system for public water supply network leakage treatment, identified key problems according to local conditions, planned and implemented projects to control pipeline leakage, systematically solved pipeline leakage problems, adhered to the balance of problem orientation and goal orientation, and adopted a system governance, step-by-step implementation, targeted management, and key breakthroughs as the basic work ideas, adopting a multi pipe system leakage control strategy. Through policy and institutional guidance, standard and normative guidance, key project implementation, and advanced technological support, Fuzhou Water Supply Co., Ltd. has planned four key engineering projects in the overall water supply network renovation project, water supply network zoning measurement project, water supply network pressure regulation project, and network intelligent construction. Through various governance measures, it has comprehensively promoted the improvement of leakage control capabilities and explored and created a set of leakage control models suitable for itself.
At the same time, Fuzhou Water Supply Co., Ltd. continues to increase investment in digital water services. In 2017, it commercialized the first batch of intelligent remote transmission water meters using NB IoT transmission technology nationwide. Intelligent water meters can monitor the operation status and water volume data of water meters in real time, timely inform users of water usage abnormalities, improve measurement accuracy, effectively reduce apparent leakage, and protect the legitimate rights and interests of users. Introducing and developing a digital twin system for water supply network, achieving real-time and accurate simulation of network operation, with a timely repair rate of over 98%. At the same time, a production and sales gap analysis system, a hydraulic model system, an intelligent scheduling platform, a GIS comprehensive service platform, a secondary water supply management platform, and a remote meter reading management system have been built and continuously upgraded. Through a large number of digital water technology applications, the entire process of water supply production, scheduling, and service has been comprehensively optimized, greatly improving the water experience of residents.
In 2021, Fuzhou Municipal Water Supply Co., Ltd. was awarded the first 5A level water supply service enterprise in a provincial capital city in China. In 2024, the leakage control case in Fuzhou City was included in the replicable policy mechanism list for urban public pipeline leakage control by the Ministry of Housing and Urban Rural Development, and was distributed and promoted nationwide.