钱塘江畔新家园，值得“蛏”赞

Group 1 - The discovery of the Chinese freshwater clam indicates a healthy aquatic environment, as it requires specific water quality conditions to thrive, such as a minimum dissolved oxygen level of 5 mg/L and a pH range of 6.8 to 7.5 [4][5] - The presence of the clam in the Qiantang River reflects a harmonious coexistence between nature and urban development, highlighting the importance of maintaining ecological balance in modern cities [4][6] - The Qiantang River in Hangzhou is being actively monitored and protected, with a total length of 17.39 kilometers under the jurisdiction of local community river guardians, ensuring the water quality remains stable at Class II standards [5][6] Group 2 - Since 2018, the Binjiang District has implemented comprehensive water environment management, achieving "zero direct sewage discharge" across the area, which has significantly improved water quality [6] - The district has also enhanced flood prevention measures, raising standards to withstand a 300-year flood event, while continuously working on the management of small water bodies to further improve overall water quality [6]