It is a line manhole and is built on the top of the vibrated reinforced concrete pipeline. This manhole type is built for the following reasons:
there are no interruptions on the line, overflowing and restrictions of the capacity load;
easy to lay just like a pipe;
lower total cost considering laying + special manufactured product;
safe hydraulic tightness and leaks reduced to zero;
from the top of the pipe (where the manhole pipe is obtained) to the natural ground level or finished level we introduce the various monolithic raising elements of different diameters and heights.