DW are supposed to be on their own dedicated electrical circuit. If you do not use an air gap, then the drain line needs to be looped under the counter and attached so that it can kink. To be able to pull the DW out and put it back in the space, I use steel braided flex hose. In my case, I tapped the water line in the basement, put in a cut off valve, then came through the floor in the back with the flex line. The water could come from the sink cabinet just as well.