You could do this with Type 4 pumps. Type 4 pumps are basically rating
curves where you enter up to 10 pairs of depth/flow values. You could
model each of your pumps to do what you need. Note that you must enter
IPRATE=1 on the BB line to be able to use more than 3 pairs of values
for the rating curves.

Reinhard Sprenger
rsprenger@UMAGROUP.COM