Abstract: An apparatus is disclosed herein for interconnecting a plurality of waste water sources in a building which includes a gravity flow conduit arrangement for conducting waste water from the sources to a storage device via a diverter or check valve. A distribution arrangement is operably coupled to the storage device for selectively withdrawing the collected waste water and for dispensing the waste water to predetermined outlets such as earth irrigation devices or the like. The conduit arrangement includes the diverter valve for directing the waste water flow into the storage tank while prohibiting flow-back of contaminated toilet water.