Hello Candidate,

The sever systems are made and developed for the purpose to easily drain out and pass the flow of waste water to its desired location without contaminating with other water bodies and nearby environment.

The cross section for severs- is different in most cases, as it depends on the flow velocity and the amount of waste transported through it's channel. Hence, the manufacturer keeps an upper level of the pipe sustainability and life period without much wear and tear.

Hope it helps!!

Have a Good Day.