Q1: The sewage is pumped up

ANS:E - all the above.

1. From low lying areas: In low lying areas, gravity may not be sufficient to naturally convey sewage to treatment plants or disposal sites. Therefore, sewage pumping stations are installed to lift the sewage from these low lying areas and facilitate its transportation to higher elevation points where gravity can then assist in its flow.
2. From basements: In buildings and structures with basements, wastewater from sinks, toilets, and other plumbing fixtures located below the level of the main sewer line must be pumped up to connect with the main sewage system. Sewage ejector pumps installed in basement sump pits or sewage ejector systems are commonly used to lift sewage from basements to higher elevation points for proper disposal.
3. Across a high ridge: In areas where a natural or man-made ridge obstructs the flow of sewage, pumping stations are employed to lift the sewage across the high ridge and transport it to the downstream side where gravity can then facilitate its further conveyance. These pumping stations help overcome topographical obstacles and ensure the efficient transport of sewage from one side of the ridge to the other.

In all of the above scenarios, sewage pumping stations play a crucial role in ensuring the effective collection and transportation of sewage to treatment facilities or disposal sites, overcoming gravitational limitations and topographical challenges where necessary. These pumping systems utilize pumps and associated infrastructure to lift sewage vertically or horizontally as needed, enabling the proper management and treatment of wastewater.