The report of the 19th National Congress of the Communist Party of China proposed that "building ecological civilization is a millennium plan for the sustainable development of the Chinese nation", and made a strategic plan to speed up the reform of the ecological civilization system and build a beautiful China; the Fifth Plenary Session of the 19th Central Committee stressed that adhering to the concept that green water and green mountains are golden mountains and silver mountains, and clearly put forward that "governing the urban and rural living environment, promoting the full coverage of urban sewage pipe network, and basically eliminating urban Black Mountains" "Odorous water" and other target tasks. Sewage treatment is an important link to improve environmental quality and promote green development. Scientific pricing of sewage treatment is the basis of establishing a long-term mechanism of water pollution control. The key to scientific pricing is to accurately grasp the cost of sewage treatment and analyze the law of cost change. At present, there is a lack of comprehensive integration of national sewage treatment cost information and in-depth research and analysis. By summarizing the public disclosure information of Listed Companies in sewage treatment industry in Shanghai and Shenzhen A shares, we calculate the level and composition of sewage treatment cost, and analyze the cost change trend. The relevant conclusions can be used as a supplement to the existing understanding of sewage treatment cost.

1、 Calculation and analysis of sewage treatment cost

After screening, a total of 8 listed sewage treatment companies with good information disclosure in Shanghai and Shenzhen A shares were selected as research samples. According to the annual report of sewage treatment business related costs and sewage treatment business volume and other information, the unit cost of sewage treatment is calculated. From 2017 to 2019, the average unit cost of sewage treatment of listed companies is 1.1855 yuan / m3, of which the average treatment cost is 0.8984 yuan / m3, accounting for 75.78% of the total cost, the average period cost is 0.2609 yuan / m3, accounting for 22.00% of the total cost, and the average tax and surcharges is 0.0263 yuan / m3, accounting for 2.22% of the total cost.

The treatment cost and period cost increased year by year, accounting for a relatively stable proportion of the total cost. Taxes and surcharges fluctuated in three years, accounting for a slight decline in the proportion of the total cost year by year. In the composition of treatment cost, the largest cost item is depreciation and amortization, with an average of 0.3284 yuan / m3, accounting for 36.56% of the treatment cost,

According to the distribution of sewage treatment capacity of the research samples, the annual sewage treatment capacity is divided into three intervals: less than 500 million cubic meters, 500-1 billion cubic meters and more than 1 billion cubic meters. It is estimated that the three-year average cost of sewage treatment in 2017-2019 is 1.2272 yuan / m3 for those with a total amount of sewage treatment less than 500 million cubic meters, 1.2325 yuan / m3 for those with a total amount of sewage treatment between 500 million cubic meters and 1 billion cubic meters, and 1.1088 yuan / m3 for those with a total amount of sewage treatment more than 1 billion cubic meters.

2、 Comparative analysis of sewage treatment cost, sewage treatment fee and sewage treatment service fee

According to the "average water price of sewage treatment sector" disclosed by listed companies, the sewage treatment service fee can be sorted out. In 2019, the average level of sewage treatment service is 1.74 yuan / m3, the highest level of sewage treatment service charge in Southwest China is 2.28 yuan / m3, and the lowest level of sewage treatment service charge in Northwest China is 0.89 yuan / m3. Compared with the full cost of sewage treatment of Listed Companies in the sewage treatment industry of 1.30 yuan / m3 in 2019, there is an average profit margin of 33.8% per m3 of sewage treatment. Taking the sewage treatment fee standard of 36 large and medium-sized cities in China as an example, the average sewage treatment fee standard for residential water is 1.0 yuan / m3, the average sewage treatment fee standard for non residential water is 1.52 yuan / m3, and the average sewage treatment fee standard for special water is 2.0 yuan / m3. As a whole, the sewage treatment fees of 36 large and medium-sized cities are lower than the sewage treatment service fees represented by listed sewage treatment companies. As a basic public service, sewage treatment is the responsibility of the government. When the sewage treatment fee is not enough to pay the sewage treatment service fee, the government should make up for it with financial funds. According to the previous field investigation on sewage treatment cost organized by us, the relevant departments of local governments generally said that there was pressure on the revenue and expenditure of sewage treatment.

The above situation shows that there is imbalance and irrationality between the sewage treatment fee charging standard based on the sewage treatment cost and the sewage treatment service fee payment standard, which has not yet reached the "(sewage treatment fee) charging standard. It is necessary to compensate the operating costs of sewage treatment and sludge disposal facilities and make reasonable profits" and "urban sewage treatment fee standard and sewage treatment service fee standard" The cost standard is about the same.

3、 Countermeasures and suggestions

1. Improve the practicability of cost information disclosure of listed sewage treatment companies. Although the content of information disclosure of listed companies is richer than before, there are still some deficiencies in the information disclosure related to the main business operation, especially the disclosure related to the operation, cost-benefit and business volume of different industries, products and regions, as well as the lack of sewage treatment methods such as distinguishing different daily treatment capacity, technical routes and effluent standards Cost information. In order to make the report users have a more comprehensive understanding of the relevant situation of listed companies, we should focus on strengthening the practicability of information disclosure, reducing or avoiding subjective description, presenting more specific financial and business volume indicators, and enriching the information dimensions of business disclosure.

2. Integrate cost data and information to improve scientific decision-making. The responsibility of formulating sewage treatment standard and sewage treatment service fee standard belongs to different departments. The cost information between departments is not smooth enough. There is imbalance and mismatch between sewage treatment service fee standard and sewage treatment fee standard, which leads to the imbalance of sewage treatment revenue and expenditure. Cost is the basis of price. We should formulate relevant systems, set up unified indicators, integrate the cost data of various functional departments, establish basic information platform, change the status quo of scattered data, realize information sharing, and consolidate the basis of administrative decision-making.

3. Carry out regular cost investigation and establish cost evaluation system. With the promotion of ecological civilization construction, the introduction of various reform measures, the improvement of treatment process requirements, the increase of investment in infrastructure and upgrading, the cost structure and level of sewage treatment will change more obviously and frequently. Regularly carry out cost investigation and research, comprehensively and timely grasp the cost information, combined with in-depth analysis of typical cases that fully reflect the green, energy saving and economic effects, deeply analyze the cost change trend and market dynamics, bring environmental capacity, economic development level, government's ability to pay, high-quality development of the industry and other factors into the cost research system, and put forward the sewage treatment benchmark enterprises Industry cost and industry standard cost level provide support for scientific price regulation.