Xinhua News Agency, Wuhan, May 17 Question: Water quality continues to deteriorate! The Central Ecological and Environmental Protection Inspector again named Honghu Lake

Gao Jing and Tian Zhongquan, reporters of Xinhua News Agency's "Xinhua Perspective"

The song "The Waves of Honghu Lake Beat the Waves" has made Honghu Lake a household name. The lake with clear water and lotus leaves touching the sky makes people yearn for it. However, the reporter from "Xinhua Viewpoint" took a boat on the surface of Honghu Lake a few days ago, and found the lake muddy and yellow, so it was difficult to find the beauty of the past.

The lake water is extremely turbid, submerged plants have almost disappeared, and the diversity of benthos has decreased... Recently, the reporter accompanied the Fourth Central Ecological Environmental Protection Supervision Group to inspect in Hubei and found that in recent years, the protection and management of Honghu Lake has been ineffective, the water quality has continued to deteriorate, and has been stagnant in Category V for three consecutive years, with a series of water ecological problems superimposed.

　　 The water quality has been classified as Class V for three consecutive years, and is rated as "the worst in history"

Honghu Lake is the largest freshwater lake in Hubei, an important regulation and storage lake and ecological barrier in Jianghan Plain, and one of the most representative lake wetlands and biodiversity areas in the middle and lower reaches of the Yangtze River. The inspection team pointed out that since 2012, the water quality of Honghu Lake has continued to deteriorate, and it has been classified as Class V since 2021.

This is not the first time that the central ecological and environmental protection inspector has paid attention to Honghu Lake. As early as 2017, the first round of supervision feedback pointed out that the water quality of Honghu Lake deteriorated from Class II in 2011 to Class IV in 2016.

The inspector pointed out that at present, the coverage of aquatic vegetation in Honghu Lake is low, accounting for only 12% of the total lake area, less than 1/5 of the historical good level since records were kept. Submerged plants have almost disappeared, and the area of wild red lotus has greatly decreased. The diversity of benthos decreased, and the number of species was only 1/4 of the historical good level since records.

The reporter learned that the structure of fish in Honghu Lake has also changed significantly. Previously, it was dominated by large migratory fish in the Jianghu, but now it is mainly carp, crucian carp and other lake dwelling fish.

"Honghu Lake has reached the worst water quality in history in the past two years," said the inspectors

The local people told the reporter that the Honghu Lake was clear and clean before, and you can see the water grass at the bottom of the lake when you swim in the water. Now the lake is turbid and the water grass is gone.

　 Expose governance "arrears"

Inspectors said that there were many "arrears" in the local governance of Honghu Lake.

——The problem of direct discharge of urban domestic sewage is prominent. At the Leijiadang Rainwater Pump Station in Jingzhou City, a large amount of black sewage kept pouring out of the drainage outlet into the direct drainage channel - this was the scene seen by inspectors during their previous covert inspection.

On April 19, 2024, the inspection team found that a large amount of rainwater and sewage mixed water in Leijiadang was directly discharged into the river. (Picture provided by the inspection team)

Honghu Lake is the main receiving water body for drainage in the main urban area of Jingzhou City, Jianli City, Jiangling County and other cities and towns. The inspector found that a large amount of mixed rainwater and sewage water in the main urban area of Jingzhou City was directly discharged into the river channel through six rainwater pump stations, including Leijiadang. The monitoring results show that the chemical oxygen demand concentration of the drainage outside the Leijiadang rainwater pump station is 149 mg/L, and the ammonia nitrogen concentration is 15.8 mg/L, which are respectively 2 times and 2.2 times higher than the Class A standard of the Discharge Standard of Pollutants for Urban Sewage Treatment Plants.

At the same time, the inspector found that there were problems in Jianli City, Jiangling County and other places where rainwater pump stations directly discharged mixed rainwater and sewage, and domestic sewage directly.

——Aquaculture is seriously polluted. Jingzhou City is the largest city of freshwater aquaculture production in China, and the pollution problem of aquaculture in Honghu Lake basin is prominent. According to public data, Jingzhou will have an aquaculture area of more than 1.8 million mu in 2022. The inspector pointed out that a large amount of untreated aquaculture tail water was discharged into the main canal of the four lakes through ditches and finally into Honghu Lake.

The reporter learned that Hubei Province will print and distribute relevant plans in 2021, requiring Jingzhou City to complete 62% of the tail water treatment of aquaculture ponds by 2025. As of the time when the inspectors entered, the area of Jingzhou City that had completed the transformation and treatment of aquaculture ponds only accounted for 13.2% of the total area.

In addition to aquaculture ponds, the area of shrimp and rice comprehensive cultivation in Honghu basin of Jingzhou City exceeds 2 million mu, and the pollution of aquaculture tail water has not been included in the control plan.

In addition, in terms of livestock and poultry breeding, four of the eight large-scale breeding farms randomly inspected by the inspection team have problems. Some of them drain pig breeding feces into ditches outside the farm, and some drain breeding wastewater into surrounding water bodies through private hoses

——Ecological protection and restoration are still not in place. The inspector pointed out that the Planning for the Protection of Honghu Lake in Hubei Province requires that wetland plant restoration sites should be set up in important estuaries and areas with sparse vegetation, such as the southeast and southwest corners of Chatan and the inlet of Xiaxin River, 327.8 hectares of submerged vegetation with strong disturbance resistance should be planted between Chatan and Jintan, and 405.4 hectares of floating leaf plant community should be restored in Qingshuibao Demonstration Area, The inspector found that none of the above projects were implemented.

　 On May 12, 2024, the inspection team found that the wastewater of a livestock and poultry breeding cooperative in Jianli City was directly discharged into the ditch. (Picture provided by the inspection team)

　 Not hard and slow as the overall implementation is not enough

The inspection team pointed out that Jingzhou City and relevant departments were afraid of difficulties in the ecological protection and management of Honghu Lake. They were not determined enough to do things hard and slowly. The overall planning of the river basin was not effective, and the main measures to promote the implementation of pollution control and ecological protection of Honghu Lake were not in place.

"A lot of basic work has not been done before," the inspector pointed out. For example, the Plan for the Protection of Honghu Lake in Hubei Province requires that the rainwater and sewage diversion transformation of the combined drainage system in the existing built-up area should be completed by 2025. However, at present, the second round of pipe network inspection in Jingzhou City has only completed 65% of the urban area. The problem of wrong connection and mixed connection is still serious. The pipe network construction and transformation is slow, and the problem of direct sewage discharge in some regions is prominent.

At the same time, the inspectors also reported that the Several Opinions on Accelerating the Green Development of Aquaculture jointly issued by the relevant national departments in 2019 required all regions to accelerate the introduction of standards for the discharge of pollutants from aquaculture tail water. In July 2022, the implementation plan of Hubei Province's agricultural and rural pollution control campaign issued also requires the development of provincial standards for the discharge of pollutants from aquaculture tail water. As a major aquaculture province, Hubei Province is not so urgent and has not issued relevant standards.

Li Enhua, a researcher of the Institute of Precision Surveying of the Chinese Academy of Sciences, has long focused on the study of the governance of Honghu Lake. In his opinion, the deterioration of Honghu Lake's water environment and water ecology has multiple causes. Domestic sewage, agricultural non-point source pollution, livestock and poultry breeding wastewater, aquaculture tail water and other pollutants have been flowing into Honghu Lake for a long time, resulting in the continuous deterioration of the water quality of Honghu Lake, the degradation of aquatic vegetation, especially submerged vegetation, and the weakening of water self purification capacity.

Honghu Lake is a shallow lake with an average water depth of only 1.35 meters. The sediment loses vegetation protection and is easily disturbed by wind and waves. However, long-term purse seine aquaculture further aggravates sediment deposition and eutrophication. Under the influence of wind and waves, sediment suspension is strong, lake water is turbid, transparency is low, and restoration of aquatic vegetation is difficult, which further affects the self purification ability of water bodies, thus forming a "vicious cycle of water quality deterioration and vegetation degradation".

How to suit the remedy to the case? Li Enhua believed that the governance of Honghu Lake could not be achieved "overnight". Instead, we should adhere to the "systematic governance and scientific policy", adhere to the comprehensive governance idea of "upstream and downstream, left and right banks, inside and outside the lake", scientifically and rationally formulate the overall restoration plan of Honghu Lake, focus on the key points, step by step, focus on strengthening the comprehensive remediation of basin pollution and normalized monitoring research, and improve the basin water management system, Gradually improve the water ecological environment of Honghu Lake. At the same time, strengthen the restoration of aquatic vegetation, improve biodiversity, and improve the structure and function of the ecosystem.

The inspectors pointed out that Hubei is known as the "province of thousands of lakes", and the task of lake ecological protection is heavy. The lake governance involves a wide range of departments, and the coordination task is heavy. It is necessary to strengthen the responsibility and assessment of the river and lake director system to prevent improper governance and perfunctory behavior.