With proper engineering, a composter can drain leachate through 1 to 2 in. (25.4 to 50 mm) drain pipe. This large size prevents clogging by solids and allows larger volumes, should a flush toilet be used.

Note: Drain lines should be vented. Many codes require separate venting for any drain system, but you might be able to use your composter’s vent system.

Install a union (an easily separated connection) between the composter and a vented drain to allow servicing of the drain line. If you can, place the composter on a raised platform, so leachate will drain out by gravity (and maintaining the composter will be more convenient).