I have seen basements where there are drains in the floor also, but ours does not have one. I guess that if the washer were to overflow, it would probably flow onto our floor. Hopefully that won't happen. If it does, we might have to replace the floor if it gets ruined, but I'm not going to worry about that now.
Also, we have a tankless water heater, so there is no water tank to worry about.