New Manholes / Public Design

In cities, manholes can be seen everywhere, for they play an important role in daily drainage and pollution discharge. Nevertheless, there are many problems. For instance, the covers of manholes will be stolen by lawbreakers to in exchange for money from time to time, leading to the occurrence of many accidents; if a large-scale flood takes place in cities, covers of manholes should be opened to increase the drainage. If the amount of water is too large, the manholes will be inundated by water, contributing to pedestrians’ failure to correctly judge the position of manholes. If there is no warning board, pedestrians will be easily fall into m