In response to the failing mechanisms of hydrological management in the Lower Yangzi Delta in the fifteenth century, some officials and local specialists collaborated to form a new strategy, which was in opposition to that used in the conventional practice, to solve the problems. Regular maintenance approach was adopted to replace crisis–response approach, and building polder dikes was prioritized higher than dredging major waterways. In doing so, they not only brought precedents under scrutiny to work out feasible policies but also focused on the issues of institutional coordination, fundraising, and mobilization of labor. The reform, which they carried out by redefining responsibilities of the state and the people and by redistributing duty to the influential and wealthy, enabled the state to play a more active role in hydrological management to better benefit local society.