检查井也是属于城市排水系统的一部分，它的主要作用是防止埋在地下的雨水管淤积堵塞，便于清淤而设置的。主要表现为圆型 的铸铁井盖（现在多有复合材料的），一般在市政道路上依据道路宽度 等级 等的不同大约70-120米设置一道。
The inspection well is also a part of the urban drainage system. Its main function is to prevent the rainwater pipe buried in the ground from silting up and blocking, which is convenient for dredging and setting. It is mainly shown as a round cast iron manhole cover (now there are many composite materials), which is generally set up on the municipal road according to the width grade of the road about 70-120m.
污水检查井是排水管道系统上为检查和清理管道而设立的窨井。同时还起连接管段和管道系统的通风作用。相邻两井之间管段应在一条直线上，因此，在管道断面改变处、坡度改变处、交汇处、高程改变处都需设置检查井，在过长的直线管段上也需分段设置检查井（根据管道直径和雨、污水类型规定分段间距）。
Sewage inspection well is an inspection well set up on the drainage pipeline system to check and clean up the pipeline. At the same time, it also plays the role of ventilation connecting the pipe section and the pipe system. The pipe section between two adjacent wells shall be in a straight line. Therefore, inspection wells shall be set at the change of pipeline section, slope, intersection and elevation. Inspection wells shall also be set in sections on the long straight pipe section (according to the pipe diameter and the type of rain and sewage, the interval between sections shall be specified).