RO Wastes Water

I want to install an under counter type filter in my basement and pipe the purified water to a sink mounted spigot and my ice maker.

I understand that the RO unit produces waste water.

Do I have to have access to a drain to dispose of this water?

As you’ve indicated, there needs to be access to a drain for the rejected water. Also keep in mind, that the water pressure needs to be high enough, to provide purified water at a satisfactory rate. If it’s low, a booster pump might help.

Hope you succeed.