As sewer system networks age, the risk of deterioration, blockages and collapses becomes a major concern. As a result, municipalities worldwide are taking proactive measures to improve performance levels of their sewer systems. Nonemergency sewer line cleaning and inspecting sewer lines are critical to maintaining the capacity of the sewer and maintaining a properly functioning system. All of these activities further a community’s reinvestment into its wastewater infrastructure. There are many different types of inspection techniques, such as closed-circuit television (CCTV), cameras and visual inspections.
One of the most frequently used and cost-efficient methods of inspection is television inspections. These inspections are ideally done when the sewer is at low-flow conditions to examine the inside condition of the sewer pipe. CCTV inspections are recommended for pipes with diameters of 4 to 48 inches. In sewers with a larger diameter than 48 inches, the camera must be attached to some sort of floatation device to ensure that it drifts from one manhole to the next. Completing this in sections guarantees that any damaged area in the pipe is not overlooked. When you are inspecting areas that are over a thousand linear feet apart, camera inspections are done regularly. This process uses a raft-mounted film camera with a strobe light. This process requires less power than the CCTV and is much more manageable. Inspections using a camera are documented on Polaroid still photos that are logged according to date, time and location.
Lastly and one of the most important types of inspections is visual. They are imperative in fully comprehending the exact condition of a sewer structure. Visual inspections of manholes and pipelines consist of surface and internal inspections. Operators inspecting surface areas should pay close attention to depressed areas on the ground above any sewer system. These areas could have visible ponding water. Additionally inspectors should thoroughly check the physical conditions of stream crossings, the condition of manhole frames and covers, and the visibility of these areas.
There are many different methods in properly inspecting sewer systems for areas throughout the United States and some of these areas might have specific procedures that must be followed, so make certain that all local requirements are being adhered too.