graded surface meaning in English

表面分级；分级表面
分级表面

It is forbidden to travel , swim or carry out other activities within the first - grade surface sources protection zones for domestic and drinking water that may possibly cause pollution to the water body
禁止在生活饮用水地表水源一级保护区内从事旅游、游泳和其他可能污染生活饮用水水体的活动。
It is forbidden to construct or expand within the first - grade surface sources protection zones for domestic and drinking water , any projects that have noting to do with water supply facilities and protection of water sources
禁止在生活饮用水地表水源一级保护区内新建、扩建与供水设施和保护水源无关的建设项目。