UUGG awful, been there. (don't buy a house where the washing machine is up on a box...how do I know??).
Even if it's infrequent, it's such a mess, maybe a sump pump or French drain is the inside trench, I think. And redoing the grading can also help, but right now, it's going to be all you can do to get it dry. Lots of dry thoughts headed your way!