AWWA REUSE52144

In many locations, dual distribution systems have been constructed to deliver reclaimed water for nonpotable uses. Most often these uses are associated with landscape and residential irrigation. Clearly there are other domestic water demands such as toilet flushing which do not require potable water. To date, however, few other nonpotable water demands in the residential sector have been investigated. This is primarily because of the cost of new plumbing to provide reclaimed water within residential homes and the understandable concern about potential cross connections. At the same time, it is well recognized that opportunities to conserve potable water do exist within residential homes. The City of Altamonte Springs, Florida conducted a pilot study in which a residential home was plumbed to use reclaimed water for toilet flushing. The home was equipped with two toilets and automatic lawn irrigation system. For the test home, a potable water meter records water used in the sinks, showers, and laundry within the home; a reclaimed water meter measures flows for toilet flushing and irrigation. Records were kept of the material and labor costs associated with the retrofit. Based on this pilot study, average water use associated with residential toilet flushing was 39 gallons per day (gpd). The use of reclaimed water for this purpose could eliminate potable water use in toilets for a cost of $2.60/1,000 gallons. The use of low flush toilets would be expected to conserve 21 gpd at a cost of $1.45/1,000 gallons. Includes tables, figures.