I have to design a irrigation pumping station for a 14 storey apartment with 4 basement for its surrounding areas. The space for irrigation reservoir and pumping station is allotted in the 4 basements. Height of each basement is 3.6m.

I am planning to have reservoir on top 2 basements to take advantage of positive suction and my pump room below .Can anyone suggest me size of pump room ,type of pumps to be used?.

Reservoir capacity = 480m3
Reservoir is to be feeded by Treated water and potable water(in case of emergency)
Pumping rate(assuming 6 hours duration)=25lps
(One duty,One assist planned)

If reservoir and pumping station is located on the same level the flow and head needed is estimated to be 25lps and 55m.But in this case the bottom of the reservoir is located at 5m above the pump room suction header and also the reservoir effective storage depth is 5m.

Here my questions are
If there any alternative Duty,Assist,Standby model which will best suit this situation?.
How to arrive at the head now ? .
What kind of pump we have to select for this situation?.
Is there any special instruments/equipments needed in this case?.
Is there any good forum /website to know more about pumping station designing in detail ?.

I expect your valuable guidance.
With Thanks,