Su Dongpo went to Hangzhou twice to serve as an official, for a total of about five to six years. It was during these five or six years that Su Dongpo left a record of renovating the West Lake in the history of Hangzhou.

The first time Su Dongpo came to Hangzhou to serve was in 1069 AD. In that year, Su Dongpo was thirty-six years old. His official position was Tongpan, which was a local official below the magistrate. After Su Dongpo took office, he devoted himself to the investigation and research of West Lake water conservancy and Hangzhou's urban development. The dredging of West Lake depended on the smooth flow of six wells. Su Dongpo decided to first carry out large-scale unblocking repairs on the six wells in Hangzhou.

In 1070 AD, Su Dongpo was transferred away from Hangzhou as soon as the six wells restoration project started. Even Su Dongpo himself did not expect this. Sixteen years later, in 1086 AD, at the age of fifty-four, he came to Hangzhou for the second time to serve as magistrate. Sixteen years ago, he once again raised his desire to dredge the West Lake. At that time, the condition of the West Lake was very bad. The lake surface had shrunk due to siltation of weeds and was on the verge of being abandoned. Hangzhou's agriculture, handicraft industry, transportation industry, people's lives and the development of the entire city are all threatened. Once the West Lake is destroyed, not only the thousands of hectares of farmland along the lake will lose their irrigation water source, but also the fish, shrimp, water chestnuts and other aquatic life in the West Lake itself will also be completely lost. At that time, Hangzhou was one of the cities with the most developed wine making industry in the country. Once West Lake was destroyed, the wine making industry would be unsustainable, and the imperial court would also lose its huge wine industry tax revenue. In addition, there were two canals in Hangzhou at that time, Maoshan and Yanqiao. They ran from north to south and were connected to the Jiangnan Canal. They were the lifeblood of transportation in Hangzhou. During periods when the lake is plentiful, they use the West Lake as their water source. Not only are the rivers smooth and silt-free, but the river water can also be used by urban residents. But as the lake water dries up, the canal has to rely on water from the Qiantang River. As a result, the salt tide intrudes, and brine is removed along the river. In addition, a large amount of sediment will be deposited into the canal along with the salt tide, so the canal must be dredged every three to five years. , the cost is very huge. What's more serious is that with the destruction of the West Lake, the residents of Hangzhou will be trapped in salt water and bitter water, and the survival of the people will be problematic. Faced with such a serious threat, Su Dongpo, who had a vision for urban construction and development, made a plan to comprehensively renovate the West Lake and build the Hangzhou water system. While reporting to the court, he raised project funds and began large-scale dredging of the West Lake.

In this large-scale dredging project of the West Lake, the West Lake has been fully dug. Su Dongpo ordered the demolition of the privately enclosed Fengtian in the lake, and built three stone pagodas in the depth of the lake near today's Huxinting Pavilion. It was forbidden to cultivate lotus root within the stone pagodas to prevent siltation at the bottom of the lake. A large amount of dredged silt was used to build a long embankment in the lake connecting the north and south shores of West Lake. Six stone bridges were built on the embankment to circulate the lake water. The entire embankment was planted with hibiscus, willows and various flowers and plants. Therefore, the scenery of the six bridges with smoke and willows adds infinite beauty to the West Lake. After the West Lake was dredged, the whole lake was filled with a pool of clear water, so a weir was built at the point where the canal connected with the West Lake, so that the Salt Bridge Canal running through the center of the city could only receive the lake water and isolate it from the river tide, thus making the eastern suburbs of the city Maoshan Canal is specially affected by river tides, and the two rivers do not interfere with each other, so that the tide does not enter the market. At the same time, Su Dongpo also recruited soldiers and migrant workers to carry out large-scale dredging of the canal. Six wells are connected, the West Lake is smooth, and clear water can be found throughout the city.

Due to the water of West Lake, Hangzhou became an unprecedented city-state in the Northern Song Dynasty, becoming the largest city in the country at that time. Ouyang Xiu, a writer in the Northern Song Dynasty, once described the prosperity of Hangzhou as "the city has gorgeous houses and more than 100,000 houses". Su Dongpo served as an official in Hangzhou for two terms. During both times he rectified the West Lake, built water conservancy, prospered the city, and benefited the people. Later generations remembered Su Dongpo and called the West Lake Causeway Su Causeway. The spring dawn on the Su Causeway is an even more fascinating sight of the West Lake.

Some people say that if it was not Su Dongpo who was an official in Hangzhou back then, but Zhang Dongpo and Li Dongpo, who were in their positions and did not seek political power, and could do whatever Xihu liked, then Xihu might not be what it looks like today. Woolen cloth. There may be some truth to this. However, history is not a canvas that can be scribbled on arbitrarily. Whether it creates blessings, disasters, or nothing for officials, history will faithfully record their whereabouts. In terms of merit, it is political achievements, and in terms of people, it is official achievements. In terms of character, what is the official's character and political performance? What has the most say is not what the official himself says, but what the official's weight is in the hearts of the people.

Thousand-year-old West Lake and Su Causeway have already stated this conclusion.