SLIDE 43: Wicking Action

Notice how the 4” pipe doubles in width in this slide as the underground water-harvesting system is revealed on the plan. It gets wider because the pipe becomes a perforated pipe covered by a root-prevention sock. This perforated pipe is surrounded by lava rock or some similar porous, inert material (BUT NOT GRAVEL). I like to use pumice, scoria, and Growstone.