I want to drain a small pump through an existing sink drain in the basement.
There is a stubout for an extra sink that was not built. The pump is rated
at 800 gph, but I doubt that it is anywhere near that given it's size. The
pump will not drain more than 20 gallons at a time. But my concern is that
this small amount will overcome the existing plumbing and start flowing out
the nearest sink hole. There will not be enough volume to do any flooding,
but any ideas for countermeausres would be appreciated. I undertsand I will
need some sort of vent for my dishwasher drain?

TIA.