[retiredguy123]

Originally Posted by Tustin714

Thanks for taking the time to reply, but we always turn off the water to the house, so overflow isn't an issue.

I understand, but accidents happen. The water shutoff valve can leak, or you can forget to remove the overflow plug, etc. I may be AR, but I would never try to disable a drain. One other thing you could do would be to cover the sink top with plastic wrap to prevent evaporation.