Sewage flows by gravity from the condominiums into the Wetwell.  Lots of people mean higher flow rates.  The pumps are designed for the highest expected rates.  This is the inlet pipe.

See this Overflow Pipe?  If the pumps fail for any reason, the level in the Wetwell will rise until it reaches the Overflow Pipe.  Sewage will then flow into the Overflow

Tank  - to be described later.  This prevents the level in the Wetwell from rising any higher than this Overflow Pipe.

Pump #1

 

Pump #2

Pump Rails

Outlet pipes for each pump.  These pipes carry the sewage from the Wetwell, through valves outside the Wetwell, to the Force Main.  The Force Main is the buried pipe that carries the pumped sewage to the Hotel.

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