can not model a pump station between two reservoirs

[pedramjazayeri]

Hi everyone,
I am trying to model a real water distribution network including 2 reservoirs and a pump station with 4 pumps between these two reservors.
The first reservoir is supplied from a water treatment but the second one in supplied from the first reservoir by the pump station between reservoirs. Also, whole nodes in the network are supplied by both of reservoirs.
How can I model the pump station between two reservoirs?
Kind Regards,
Pedram