Challenges facing the management of wastewater treatment systems in Chinese rural areas

Water pollution has become a serious issue in China's rural regions. However, wastewater treatment in these areas has not been a major concern for the government for a long time. There were 2.45 million villages in China with a total population of 0.58 billion (Ministry of Housing and Urban-Rural Development of the People's Republic of China, 2018). The sewage generated each day is approximately 17.6 million m³ (Chai 2019). However, the treatment capacity per day is only around 494,700 m³, which means that only 2.8% of wastewater is treated (Ministry of Housing and Urban-Rural Development of the People's Republic of China, 2018). The discharged wastewater generates all kinds of hazards (Ju et al. 2016; Zhao et al. 2017). As everyday activities utilise greater amounts of chemicals, sewage becomes more heavily contaminated (Yu et al. 2015). Also, faeces are no longer recycled to farming land in the traditional rural manner but are instead discharged into the environment after basic treatment. Thus, sewage spreads on the surface and then accumulates in ditches and pools, drawing large numbers of flying insects, especially mosquitos (Sun & Ma 2010; Piasecki 2019). Accordingly, these highly polluted bodies of water cause a lot of illnesses in these regions. Liu (2010) found approximately 459 villages with prevalent rates of cancer in China. Wang & Pan (2014) note that the total value of health damage caused by polluted water in Chinese rural areas increased from 1 billion to 2 billion between 2004 and 2009.

In response to this worsening situation, the government has introduced policies and programmes such as the ‘New Rural Construction’ initiative for sewage treatment projects in villages. Wastewater treatment systems (WTS) can effectively improve water quality and the environment in rural areas (Wu et al. 2011; Poortvliet et al. 2018). With subsidies and promotions from the government, thousands of WTSs have been constructed in villages. Figure 1 indicates that the number of villages equipped with WTS increased rapidly. According to the (National Bureau of Statistics of China 2018), nearly 25% of villages in China have WTSs. However, many of these wastewater treatment plants have gradually fallen into ruin (Hu et al. 2016). For example, in Hainan, around 70% of the constructed WTSs operated for 3–5 years and then stopped (data were sourced from interviews with officials). The same situation exists in other provinces.

The smooth and continuous operation of a wastewater treatment plant relies on suitable technology, sufficient financial support, and effective governance structure (Bakir 2001). Most of the technical problems in WTSs of rural areas have been discussed in the literature because tailor-made designs are often necessary for different villages (May et al. 2009; Dong et al. 2012; Xu et al. 2019; Xu 2021). However, the governance and maintenance of these systems are rarely analysed. Insufficient finance on operation and maintenance (O&M) and ineffective governance structure could impede the continued operation of treatment plants (Liang &Van Dijk 2010; Liang et al. 2020).

This paper presents an in-depth study of the challenges in the management of WTSs in rural regions. Furthermore, the cases of Zhejiang and Hainan provinces have been analyse separately in terms of success and failure in operation, respectively. We conducted extensive field works in the villages of Hainan and Zhejiang provinces. Specifically, we observed the WTSs in villages in Hainan province from 2010 to 2018 and selected a village called Dala as a representative case for intensive analysis. Conversely, the examination of WTS in Zhejiang province was implemented from 2016 to 2020. Compared with villages in Hainan, those in Zhejiang adopted a similar and suitable WTS management mode. All data for both cases were collected through interviews with relevant county/town governmental officials, village committees, and farmers. The experience of Chinese rural areas in wastewater treatment can guide other developing countries that are also suffering from rural environmental pollution (Perreault 2005; Whittington et al. 2009; Schweitzer & Mihelcic 2012).

For many years, Chinese rural areas lacked any WTS. However, as the natural environment deteriorated in these areas, more rural residents started demanding for improvements in sanitation and provision of potable water (Jin et al. 2014).

From 2005, the Chinese government began to put more effort into and financially supported wastewater treatment in rural areas. Improvement in the water environment in rural regions became an important issue in the rural development strategy due to the ‘New Rural Construction’ initiative put forward by the government in 2005. Three departments were involved in the initiative, namely, the Ministry of Environmental Protection, the Ministry of Finance and the National Development and Reform Commission. Under this initiative, many demonstration projects for wastewater treatment were constructed over time in the villages of every province. However, there were no clear plans and instructions for the management of WTSs. During the period of the 12th 5-Year Plan (2011–2015), building WTSs in rural areas was perceived as key to rural environmental improvement. Therefore, the WTS numbers increased rapidly between 2006 and 2016 (Figure 1); notably, the developments of different regions are diverse. As shown in Figure 2, Shanghai, Beijing, Zhejiang and Jiangsu have had a rapid growth in the construction of WTSs over the period of 2006–2016. Zhejiang, in particular, has seen more than 80% of villages getting WTS in 2016. In contrast, other provinces still have a relatively low rate at around 20% or less (Figure 2).

As can be seen from Figure 2, the number of WTSs in rural areas rapidly increased after 2015. The ‘Plan for Preventing Water Pollution’, published by the State Council in 2015, requires the rural WTSs to have a standardised design, construction and management. Moreover, the ‘13th 5-Year Plan’ (2016–2020) aimed for a rural wastewater treatment rate of over 60%. In 2017, the 19th National Congress of the Communist Party of China (CCP) published a national initiative termed rural revitalisation to satisfy the increasing desire of rural people for a better life. In 2018, the strategy of rural revitalisation was noted for the first time and put into the General Program of the Communist Party Constitution. At the same time, the Ministry of Finance offered specific funding to support wastewater treatment in rural areas. Subsequently, the State Council in 2019 issued a policy document titled ‘Three Years’ Planning on Rural Environment Improvement,’ which prioritised rural sewage construction, garbage treatment and village beautification and further promotes on-going planning for rural construction. Table 1, which lists the investment in wastewater treatment in rural areas during the period of 2016–2018, demonstrates that the eastern region got more funding than the other regions. All these policies accelerated the development of wastewater treatment in the rural regions of China.

Each province has published its policies and measures for promoting rural WTSs. For example, Hunan province was the first to propose that the responsibility for the construction and management of WTSs should be at the county level. Jiangsu has issued a ‘3-year action implementation plan for rural residential environment improvement’ and arranged a total of 4.40731 billion yuan of funds for rural environmental improvement in 2018. Gansu, taking an experimental approach, proposed pilot projects in each county that might have different site requirements, population aggregation and so on for exploring the most effective wastewater treatment mode. Guangdong has adopted a unified sewage treatment model for the surrounding rural areas of large cities, whereas Shandong promoted toilet construction and wastewater treatment jointly. Zhejiang province was the first to invite a professional institute into their projects' O&M.

Although each province has started the wastewater treatment in a rural area, there has been a drastic difference in the progress between the provinces. In 2018, in the Zhejiang and Jiangsu provinces, Shanghai and Beijing, more than 70% of the villages already have WTSs (Ministry of Housing and Urban-Rural Development of the People's Republic of China, 2019; Xiang 2019). Conversely, the Liaoning, Gansu and Shanxi provinces have only just started constructing their demonstration projects (Ministry of Housing and Urban-Rural Development of the People's Republic of China, 2019).

Zhejiang province has 23,753 villages. Until 2019, more than 90% of the villages had built wastewater treatment facilities, which is the highest ratio among all the provinces. Zhejiang province is a rich region of China, with a rural per capita income of around 30,000 yuan in 2019 (Zhejiang Statistical Bureau 2020). Following its rapid development of wastewater treatment in rural areas, Zhejiang is currently attempting to improve the management of WTSs, whereas other provinces are still at the construction stage.

In Zhejiang, villages in mountain areas mainly adopted decentralised wastewater treatment, whereas those in plains used centralised treatment. According to the geographic feature of Zhejiang, an increasing number of villages built decentralised WTSs (Bu et al. 2014). However, a portion of the constructed WTS in Zhejiang experienced serious technical problems, such as faulty design and poor-quality construction (Wu et al. 2015).

Zhejiang was the first province to involve a professional O&M service institute in the projects' management. As can be seen from Figure 3, there are five stakeholder projects: county, town, village committees, farmers and O&M service institute. The county government is responsible for the development of the WTSs. Thus, the success or failure of the operations reflects on the leader of the county government, which helps with political motivation. Both the town government and village committees played the role of supervisors in the project management. They keep watch on the project, provided certain technical assistance and provided feedback to the county government. The farmers are beneficiaries of the wastewater treatment system but do not participate in the daily management of the project. The O&M of the wastewater treatment system was carried out by a professional service institute, which was regarded as the project manager.

In Zhejiang province, 90% of the initial investment of the wastewater treatment system is from the city/county/town governments, 10% of which is from the provincial government (sourced from the interviews). The O&M cost is covered by the subsidies from various sources. As can be seen from Table 2, 10% of the villages in Zhejiang province obtained O&M subsidies from the city government, 30% from the county government and 60% from the village committee (Wu et al. 2015). In both city and county governments of Zhejiang province, there was a specific budget for rural environment protection. Table 2 demonstrates that most villages get funding from their own village committees. There are many small industrial units in the villages of Zhejiang province, which bring a certain amount of income to the village committee. This covers the O&M cost of WTSs.

The successful implementation of WTSs depends on three factors. First, due to the active economic development in Zhejiang, there is enough financing to meet the O&M cost of WTSs. The city and county governments have a budget sufficient to support the WTSs. Meanwhile, as the industrial production in villages provides funds to the village committee, O&M spending can be drawn from that source (sourced from the interviews). Second, the projects are linked with the county government's political success, which incentivises the county government to ensure a successful and continual operation of the WTSs. Third, the professional O&M service institute provides suitable technology and cost-effective management.

The centre of the Hainan province case study is a village called Dala. Hainan province is a relatively poor region in China with a rural resident income of about 15,000 yuan in 2019. It has 2,613 villages. Until 2017, only 9% of the villages in Hainan province had wastewater treatment facilities. In Dala village, there are 275 households with a total population of 1,500. The sewage produced by the village is nearly 250 tons per day. The WTS in Dala was constructed in 2010, whose treatment capacity is around 250 m³ per day, which can basically satisfy the village's requirements.

The WTS in Dala village was designed and constructed according to the local geographic features, which employed the decentralised treatment mode. The wastewater facility in Dala village includes networks collecting wastewater and a wetland for wastewater purification. The wetland is around 700 m² and comprises a mall pool and a park that was previously the common land of the village. Its tailor-made design ensured the smooth operation of the system within a certain period. According to the interviewees, the design for many WTSs in Hainan province is faulty, which resulted in failed operations.

The governance structure of Dala village has four stakeholders involved in the project management, namely, county government, town government, village committees and farmers (Figure 4). As with Zhejiang province, the county government is responsible for the development of the projects, with the town government playing the role of supervisor. Farmers are the main beneficiaries and users of the wastewater treatment system but are not involved with project management. The village committee is the project manager but lacks professional knowledge and skills in this area. Two members of the village committee were trained just before the project's operation.

The initial investment of wastewater treatment system costs 870,000 yuan, the entire sum provided by the county governments. The O&M cost is covered by the village committee, whose revenues are derived from land rentals. Because the treatment system mainly comprises the wetland, the O&M cost is not very high. An outlay of 2,800 yuan per month covers the payment for three women who clean the wetland of 600 yuan each per month and payment for one external technician of 1,000 yuan per month. As the village committee is not a professional O&M service institute, the treatment system stopped working in 2016. To maintain the smooth operation of the system, the town government subsidised 70,000 yuan for repairs. The land rental revenue of the village committee is around 50,000 yuan per year. Hence the village committee can afford the O&M cost for the system. Unfortunately, this source of financing was terminated in 2017, after which the wastewater treatment system stopped operations and, at present, has entirely collapsed.

The failure of the wastewater treatment system of Dala village highlights several problems in the management of WTSs in rural areas. First, a major issue is the lack of a sustainable financial source for the O&M expenses. In the case of Dala village, relying on the income of land rentals of the village to pay for the O&M cost is not feasible, even though the O&M cost is not especially exorbitant. Second, neither the county nor the town governments have optional financial instruments, even though the county government is responsible for the development of the treatment system. Third, the village committee being the project manager is not motivated or experienced in managing a wastewater treatment system. The system takes 67% of the village's land rental revenues but brings in no earnings. This in essence means that long-term operation of the wastewater treatment system is impossible.

Currently, there are still various outstanding issues preventing the effective implementation of wastewater treatments in Chinese rural areas. These problems can be summarised as financial unsustainability, inappropriate governance structures and technical complexity.

Depending on the subsidies for O&M, financing is generally not sustainable or reliable. Government subsidies are not on-going because of the local leadership rotation system (Harvey 2007; Liang et al. 2020). In Chinese politics, this rotation system means that officials often do not stay in one position for long but routinely cross administrative boundaries. Such transfers risk suspending the financing of the WTSs in rural areas. Most counties and villages in Zhejiang can afford the O&M spending for a period as this province is a well-developed region. However, other regions, especially the western provinces, find it quite difficult to maintain financial support for the operation of WTSs because of their limited budgets (Chang 2020; Zhao & Wu 2021). The revenues of village committees are also unsustainable, as in the case of Dala village in Hainan province.

An optional financial plan or model for the WTSs in rural areas is lacking. The hierarchical Chinese governance structure determines that the city/county/town governments will wait for an order from the higher authority rather than create a sustainable financial source for WTSs. The local governments put most of their energy and money into completing construction and enhancing their political standing but not into ensuring the systems' smooth operation over the long-term (Yang et al. 2016; Liang et al. 2020). The local governments at various levels are reluctant to seek out other feasible financial sources, even though subsidies to the wastewater treatment system are limited (Liang et al. 2020).

According to economic theory and prior experience, private capital can ensure the sustainability of the wastewater system's operation (González-Gómez et al. 2013; Jiang et al. 2018). However, it is not easy to attract such investment for rural WTSs. Given that wastewater treatment is a public resource, there is no economic benefit. At the same time, the government lacks any incentive to design a plan for attracting private capital.

In the governance structure for WTSs of rural areas, it is the county government that has responsibility in villages. Under the hierarchical structure of water management, the county government (upper level) issues orders to the town government (lower level) and then the town government issues orders to the village (Liang et al. 2020). The town government and village committee merely execute the command without having any responsibility for the outcome. The time cost of transferring information down to various levels is increased while efficiency is decreased. In addition, the county governors tend to care solely about short-term performance rather than prioritise the long-term development of WTSs because the local leadership rotation system (Liang et al. 2020). Thus, the governance structure increases the risk of policy implementation failure even though the county government possesses absolute authority and power over their subordinates (Loughlin 1996; Hope & Chikulo 2000).

A professional O&M service institute, as implemented in Zhejiang province, is an efficient and economical mode. According to the interviews, the O&M service institute decreases the O&M costs by technically operating and efficiently managing the project. The external management support is essential to rural water management (Hutchings et al. 2015). In the case of Hainan province, the village committee is the project manager, similar to other regions. Unprofessional management of the WTSs almost always leads to severe technical problems and overspending in operations (McCommon et al. 1990). Thus, the practice of engaging a professional institute to be the project manager should be encouraged in other rural areas.

Another defect in governance is that farmers have limited knowledge of WTS and play no part in project management (Wu et al. 2015; Chu 2021). In the case of Dala village in Hainan province, less farmers were aware of the reason underlying the construction of a WTS in the village. The farmers are only aware that wastewater from their houses is collected by pipelines, which were constructed by the government. Neither village committees nor the town government considers that improving the awareness of farmers about WTS is necessary. As such, farmers are unwilling to manage WTS due to this limited knowledge about wastewater treatment. In terms of the interviews with governmental officials, other regions in China have similar situations as that of Dala village on the farmers' awareness. Being the main beneficiary, farmers using the systems appropriately and cooperatively can help maintain the smooth operation of the systems (Neef 2009). Unlike the wastewater treatment in cities, the wastewater systems in rural areas are always decentralised. In a decentralised system with a small scale, the absence of users' voices increases the risk of inefficient operation of the project (Yang et al. 2016; Chu 2021).

Chinese rural areas have various and complex geographic features, uncontrolled sewage discharge and unsystematic household distributions (Yang et al. 2016). The sewage quality differs in rural areas due to diverse economic development and living habits (Kong et al. 2021). In certain villages, the contamination in wastewater is quite high (Bu et al. 2014). All these factors increase the technical difficulties of building a wastewater treatment system appropriate for a village (Wang et al. 2019).

Compared with centralised treatment in urban wastewater systems, decentralised wastewater treatment is considered to be more suitable for rural areas (Wu et al. 2011; Xu et al. 2019). This requires that decentralised treatment systems be designed, adjusted and constructed according to each village's particular situation. However, in many instances, a centralised mode is selected, i.e. collecting and treating wastewater for several villages collectively (Yang et al. 2016). The three main reasons for this are as follows: (1) following the urban mode of building centralised system is easier than creating a tailor-made design for each village; (2) the governors would rapidly complete the construction of wastewater systems so they could cite political achievements; and (3) there are fewer qualified engineers in rural areas who can design a wastewater treatment system appropriate for each village. Consequently, the built WTSs have higher initial construction costs and then fail to operate successfully and efficiently afterwards.

The WTSs in rural areas are substantively promoted by the Chinese government since the environment in rural areas has been severely polluted. The implementation of these systems, however, remains a major challenge. First, the financial sources for the O&M costs are unsustainable. The O&M costs are covered by government subsidies or revenues from the village committee. Both subsidies and revenues are not sustainable financial sources. Meanwhile, there is currently no financial plan and initiatives to attract private capital. Second, there are various problems in the governance of WTS. Traditionally village committees managing the WTS are not efficient modes. Involving a professional O&M service institute with stakeholders could be an alternative to decrease O&M cost and increase managerial efficiency. Furthermore, the local leadership rotation system in the government and the farmers' limited awareness and lack of participation in wastewater treatment system can hamper smooth governance in WTS. Third, the technical difficulty is also a challenge to building suitable WTSs across regions. Decentralised WTSs with tailor-made designs and construction could be more suitable because of geographic variety and conditional difference. But building this type of WTS is rarely realized in rural areas in China.

This research was funded by the National Social Science Fund ‘Research on Dynamic Mechanism and Policy Guidance of China's Rural Environmental Governance’ (grant no. 17BJY061). We are grateful to the anonymous reviewers for their insightful comments.

All relevant data are included in the paper or its Supplementary Information.