On this day, 674 years ago, on April 29, 1351 (April 4, 1351 of the lunar calendar), the Yuan government issued an edict to dig the old Yellow River. On April 29, 1351 (the fourth day of April, the eleventh year of the Yuan Zhizheng), Emperor Yuan Shun issued an edict ordering Jia Lu, the minister of the Ministry of Industry, to serve as the chief river defense envoy due to serious floods and droughts. He recruited 1.15 million people from the road such as Jingliang (now Kaifeng, Henan) and Daming (a part of Hebei), and 20,000 troops to dig the old Yellow River. In May, Jalu adopted the policy of dredging the Saibei River and dredging the South River. From Huanglinggang (now southwest of Cao County, Shandong Province) southward to Baimao, and then from Huanglinggang west to Yangqing Village, the roads were dug and completed in July, with a total length of more than 280 miles. In August, water burst into the old course of the Yellow River, and in September, boats passed through. At this point, all water and soil projects have been completed, and the Yellow River has returned to its old path, converging south into the Huaihe River and east into the sea. Emperor Yuan Shun ordered Hanlin to follow the order of Ouyang Xuan to make the "Heping Monument", and Ouyang Xuan also wrote "Zhizheng River Defense Notes", which recorded Jia Lu's strategy for river management.