Inspecting large sewers can be inconvenient and costly, in part because taking an interceptor line out of service for traditional crawler-based inspection requires extensive bypassing.Furthermore, major interceptors commonly have access points spaced at 1,500- to 3,000-foot intervals, too long to inspect with camera vehicles pulling heavy video cable. Many access points are also off-road.Large sewers can be inspected while in service using cameras on floats, but because a video camera can’t see below the waterline, the inspection is inevitably incomplete. In such cases, other tools can be used to assess pipe conditions both above and below the waterline.Laser profiling looks
