Manhole can be defined as an access point into the sewer system for workers, and material. It is an important part of the sewer system because it eliminates the need for digging. For the purposes of trenchless rehabilitation, manholes are the primary way to get access into the system and rehabilitate or replace pipes without the need for excavation. They are placed at regular intervals throughout the sewer system till the treatment plant for convenient access at any point.
Trenchlesspedia Explains Manhole
The manholes are made of RCC or brick masonry and are constructed along the length of the sewer system at equal intervals or depending on the length of the pipes to be laid. . Manholes can also be found where two or more sewers meet, and where there is a change in the size of the sewer line. They also allow for changing the direction of the sewer line during the construction phase. Manholes can be used to carry out inspection, and cleaning. It also acts as a ventilation unit to prevent buildup of harmful gasses. The different types of manholes are shallow, normal, and deep depending on the location and depth of the sewer line. Access to manholes is limited to authorized workers with training and necessary safety equipment to prevent accidents due to falls, and harmful gasses like methane and hydrogen sulfide.