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Abstract: Implementing the construction supervision system represents a shift in China’s project management approach, from the traditional small-scale production model of self-financing, self-construction, and self-management to a socialized, professional, and modern management model. It is a concrete manifestation of the two fundamental transformations taking place in the construction sector. Keywords: Pipeline engineering; Water treatment engineering; Water intake engineering; Supervision. The implementation of the construction supervision system represents a shift in China’s project management approach, from the traditional small-scale production model of self-financing, self-construction, and self-management to a more socialized, professional, and modern management style. It is a concrete manifestation of the two fundamental changes taking place in the construction sector. China began to pilot the construction supervision system in the late 1980s. After nearly a decade of implementation, 29 provinces, municipalities, and autonomous regions across the country, along with 39 industrial and transportation departments under the State Council, are currently continuing to use this system. The investment scale of the supervised projects has reached 500 billion yuan. As a result, the quality of many large and medium-sized projects has been improved, project timelines have been shortened, substantial investment savings have been achieved, and significant economic and social benefits have been generated. The so-called \"construction supervision\" refers to the practice whereby social supervision agencies, entrusted by the project owner, utilize relevant construction regulations, project contracts, construction drawings, etc. to exercise comprehensive control over the quality, costs, and schedule of the construction project as well as to manage contracts on behalf of the owner. Supervision engineers, in a fair position, are responsible for coordinating among all the parties involved in the project, thereby ensuring that the construction achieves the best possible return on investment. This will enable project construction to overcome randomness and blindness, and achieve a socialized, professionalized, and modernized management model. Therefore, the construction supervision system has demonstrated its strong viability in recent years; early examples include the Daya Bay Hydropower Station in Guangdong, while modern examples include the Three Gorges Project and the Xiaolangdi Project on the Yellow River, among others. In 1997, China officially implemented the construction supervision system nationwide. The water supply industry is an important sector that affects production in various fields and the normal livelihood of the entire population; therefore, the quality of water supply project construction has a direct impact on the country’s economy and people’s well-being, and supervision systems should be implemented. Water supply systems can be roughly divided into three parts: water intake systems, water treatment systems, and pipeline networks. The key aspects of supervision are described below according to the characteristics of the three parts. 1. Supervision of water intake projects Water intake projects represent the first stage in water supply systems; currently, the main methods of water intake are groundwater extraction and surface water extraction. Among them, surface water extraction projects have more influencing factors than groundwater extraction projects; they are more complex in design and are also more widely used. The construction of surface water intake projects is affected not only by summer, winter, dry seasons, and rainy seasons, but also by the flood season and drought season of rivers. If there are problems with the quality of the water taken in, it will result in a lack of water for the entire supply system, which would be a serious disaster. Therefore, water intake project supervision must pay special attention to the reliability of the design scheme during the planning stage, and it must be thoroughly validated. Before commencement of work, the construction plan and construction organization design must be carefully reviewed; if underwater construction is involved, efforts should be made to avoid the flood season of the river. Practical construction measures must be in place to ensure construction quality. For non-standard mechanical products, their manufacturing process should also be monitored, with attention paid to coordination with civil construction work. 2. Supervision of water treatment projects Since the water treatment facilities in urban water supply systems are often of large scale, they require a large amount of land, have high demands on the foundation, and involve substantial concrete work. Therefore, the foundation needs to be treated during the construction phase; in cases where pile driving is required to reinforce the foundation, strict supervision is necessary. Careful monitoring must be carried out in accordance with relevant inspection and evaluation standards, covering aspects such as the preparatory work before pile driving, the pile-driving process, the quality of fabrication and installation of pile foundations or rebar cages, as well as the concrete mix ratio and pouring process, to ensure that the foundation treatment meets the design requirements. If the volume of the concrete foundation for the structure is large, in addition to formulating detailed measures for continuous pouring and ensuring strict supervision of their implementation during construction, it is also necessary to control the temperature of the concrete when it is poured into the formwork. Proper maintenance measures must be taken to keep the temperature difference between the inside and outside of the concrete, as well as the rate of temperature drop, within certain limits, thereby preventing temperature cracks caused by thermal stress (the temperature control parameters are generally determined based on calculations of the stresses in the concrete). Since water treatment structures generally achieve their treatment objectives through the residence time of water within them, as well as their geometric shape and size, construction supervision must pay special attention to the accuracy of the geometric dimensions of various parts of the structure. The water treatment process in a water plant is generally a continuous gravity-fed process from start to finish; therefore, it is extremely important to ensure the accuracy of the bottom and top elevations of various structures, as well as the elevations of their inlets and outlets, and the elevations of various components within these structures. During supervision, these elevations must be carefully verified repeatedly to ensure they meet the design requirements. Furthermore, preventing seepage and leakage is also a critical issue for water treatment structures; special attention must be paid to implementing measures to prevent seepage and leakage throughout both the design phase and the construction process. During the supervision process, the supervision engineer must focus on controlling the quality of concrete works. The installation of settlement joints, expansion joints, or post-cast strips is also important for water treatment structures; failure to implement them properly can lead to leaks, and these areas are key points that supervisors need to closely monitor. Water treatment machinery is often non-standard equipment; therefore, great attention must be paid to the coordination between the machinery and the civil engineering works during installation, especially regarding embedded components as well as the machinery’s requirements regarding structural dimensions and flatness. The supervision engineer must carry out proper coordination tasks. If necessary, the manufacturer’s quality assurance system should also be monitored to ensure that the products meet the design requirements. 3. Supervision of pipeline engineering Urban water supply pipelines are generally very complex, and they are typically expanded over time as the city develops. Urban water supply networks connect millions of users and are responsible for delivering water directly to them. Therefore, if the pipes burst or become blocked, repairs will affect a large area, resulting in water shortages for many users. This not only causes great difficulties in people’s lives but may also force many businesses or factories to stop operating, leading to significant economic losses. Hence, when designing these networks, it is necessary to consider ensuring a stable water supply and to take effective measures to prevent water hammer from damaging the pipes. Protective measures should also be taken under the road to prevent it from being damaged by vehicles. More importantly, in terms of the pipeline network structure, it is necessary to ensure that the scope of impact is minimized in the event of an accident. When supervising a project, attention should be paid to the above aspects during the design phase; during the construction phase, quality must be strictly controlled, and prior control over the quality of pipes and the materials used for joints is essential. During construction, aspects such as pipeline foundations, joint construction, and anti-corrosion measures must be strictly controlled in accordance with the relevant quality standards, in order to minimize maintenance needs and the occurrence of accidents during subsequent operation. Piping network construction involves a wide range of aspects, such as intersections and integrations with urban roads as well as other urban pipelines and cables. It involves a large number of users, and supervision engineers need to carry out a great deal of coordination work. Good coordination can accelerate the construction progress and reduce costs. The above discusses the key points of supervision and precautions regarding the characteristics of water supply projects; when carrying out project supervision in practice, each part and each stage must be handled in accordance with specific procedures as well as relevant standards, regulations, and inspection criteria.