How to evaluate Bai Juyi?

In 822, Bai Juyi was appointed as the secretariat of Hangzhou. During his tenure in Hangzhou, he saw that the farmland around Hangzhou was often threatened by drought, but officials refused to use the water from the West Lake to irrigate the farmland. So he eliminated many obstacles and criticisms, mobilized migrant workers to heighten the lake embankment, built dams and sluices, increased the capacity of the lake, and solved the irrigation problem of hundreds of thousands of acres of farmland between Qiantang (now Hangzhou) and Yan Guan (now Haining). Bai Juyi also stipulated that when the farmland is not irrigated, the large and small sluices and Doumen of the West Lake should be closed in time; If there is water leakage, it should be repaired in time. Bai Juyi also organized the masses to repair six wells dug by Li Bi, the secretariat of Hangzhou, in Qiantangmen and Yongjinmen in the Tang Dynasty, which improved the water use conditions of residents.

As a poet:

Bai Juyi was a great poet with great influence in the middle Tang Dynasty, a great realistic poet in the Tang Dynasty and one of the three great poets in the Tang Dynasty. Bai Juyi and Yuan Zhen * * * advocated the new Yuefu movement, and together with Liu Yuxi, they called the world "Bai Yuan" and "Bai Liu".

His poetic thoughts and creations, which emphasize popularity and realism, occupy an important position in the history of China's poetry.