bilge pump discharge

[Killick69]

I need advice on bilge pump discharge points. The manual pump outlet is into the well for outboard (exiting through the side of the cockpit locker). This seems fine to me.

I have fitted electric pump with float switch and plumped this into the exhaust line that serviced the inboard that is no longer there. This is a 40mm ID rubber hose that snakes through the cockpit locker and has a high rise loop to the top of the cockpit locker. This old inboard line exits out the stern. Is there any chance this outlet could be below water when the boat is well heeled (anyone ever followed a TH leaning to port, which is where this outlet is?). The positioning of the outlet is typical of that on most THs/most boats. With an inboard fitted, even if the outlet was submerged it would not be an issue, because it is a closed circuit up to the inlet seacock. However in my case water ingress would end up going through the auto bilge pump into the bilge.

How have you guys and gals routed bilge pump lines and is there any need for riser loops. I have gathered from other websites that one way valves are not a good idea and would rather avoid using them.