ARE THERE ANY REGULATIONS DEALING WITH GRAY WATER USE?

Graywater, also known as sullage, is non-industrial wastewater generated from domestic processes such as dish washing, laundry and bathing. Graywater comprises 50-80% of residential wastewater. Graywater comprises wastewater generated from all of the house's sanitation equipment except for the toilets (water from toilets being blackwater).

Graywater is distinct from blackwater in the amount and composition of its chemical and biological contaminants (from feces or toxic chemicals). Graywater gets its name from its cloudy appearance and from its status as being neither fresh (white water from groundwater or potable water), nor heavily polluted (blackwater). According to this definition wastewater containing significant food residues or high concentrations of toxic chemicals from household cleaners etc. may be considered "dark gray" or blackwater.

Concerns in recent years over potential health and environmental risks means that many jurisdictions demand such intensive treatment systems for legal reuse of graywater that the commercial cost is higher than for fresh water. Despite these obstacles, graywater is often reused for irrigation, illegally or not. In droughtzones or areas hit by hose pipe bans (irrigation restrictions) graywater can be harvested informally by manual bucketing. In the third world, reuse of graywater is often unregulated and is common. At present, the recycling of graywater is poorly understood compared with elimination.

A Type 1 Reclaimed Water General Permit allows private residential direct reuse of gray water for a flow of less than 400 gallons per day if all the following conditions are met:

1. Human contact with gray water and soil irrigated by gray water is avoided.
2. Gray water originating from the residence is used and contained within the property boundary for household gardening, composting, lawn watering, or landscape irrigation.
3. Surface application of gray water is not used for irrigation of food plants, except for citrus and nut trees.
4. The gray water does not contain hazardous chemicals derived from activities such as cleaning car parts, washing greasy or oily rags, or disposing of waste solutions from home photo labs or similar hobbyist or home occupational activities.
5. The application of gray water is managed to minimize standing water on the surface.

In recent years concerns over dwindling reserves of groundwater and overloaded or costly sewage treatment plants has generated much interest in the reuse or recycling of graywater, both domestically and for use in commercial irrigation. This has caused more federal and state governments research into the reuse and applications of regulations to successfully harness graywater.