I have around 4.5 metres of lift and 20 metres or more of PVC pipe from the river to my pump.
This is therefore not self-priming. I have a brass foot valve (check valve with debris screen) on the end of the pipe in the river.
It's possible that my local hardware store in Indonesia which mostly sells junk has sold me a bad foot valve. OTOH I read that maybe they just leak a lot (in my case: prime the pump, works, turn the pump on again three days later: empty), so replacing it might not solve the issue
Is there something I should usefully do, like add another check valve near the bottom of the pipe as a failsafe, replace the valve with a specific type, or whatever?