bilge pump question

[Kracker Jack]

my mind is constantly thinking of ways to consolidate on knick knacks on the boat. So I have a bilge pump question. Can I put a T fitting from 2 bilges to 1 thru -hull? or will the one bilge pump thats running pump some water reverse into the other bilge that is not working? Im trying to get away with only having 1 thru-hull fitting for 2 pumps. I realize that this is a pretty stupid question but Im just curious.