In the 1970s, an earth embankment was built near Hangzhou to resist the tide. /kloc-at the beginning of the 0 th century, a seawall was built near Hangzhou, which was the beginning of a stone seawall; During the reign of Kanggan in the Qing Dynasty, it further developed into a large stone pond with fish scales, which is still in use today.

In 1950s, the Qiantang River survey team jointly organized by Shanghai Hydropower Design Institute of the Ministry of Electric Power Industry and Survey and Design Institute of Zhejiang Water Resources Department conducted a basin-wide survey on the water resources of Qiantang River, and determined that the source of Qiantang River came from Lianhua Point at the junction of Zhejiang, Anhui and Jiangxi provinces.

1979 edition of Cihai records that Qiantang River, formerly known as Zhejiang, is the largest river in Zhejiang Province, and its upper reaches originate from the Lotus Tip at the junction of Zhejiang, Anhui and Jiangxi provinces. In the late 1970s, some scholars and journalists once again organized an investigation into the source of Qiantang River and put forward new opinions. They believe that the source of Qiantang River should be Longxi (Longtian River) in Longtian Township, Xiuning County, Anhui Province. ?

River source:

The earliest source of Qiantang River is Geography of Hanshu, which briefly puts forward that "water flows out of Danyang Yixian" in Zhejiang. Geographical Records of the Later Han Dynasty put forward that "Zhejiang went out of Shexian County". Li Daoyuan, a geographer in the Northern Wei Dynasty, affirmed this statement in the Han Dynasty. Since then, people have always regarded the upper reaches of Xin 'an River as the source of Qiantang River.

In 1930s, geographers believed that Qiantang River originated in Ma Jinxi, Kaihua County, which is at the junction of Zhejiang, Anhui and Jiangxi provinces.