Aug 19, 2006 A/C External Drain Dry Well. My A/C external drain is only 6 from the wall and I worry about the constant moisture attracting termites. What type of dry well would work best? I have thought about excavating below the foundation & filling w/ rocks/gravel, then burying a 5 gal plant pot filled w/ rocks & gravel just below the A/C drain pipe. 3