Quick Answer
A DIY grey water system requires a collection tank, a filtration system, a disinfection method, a distribution network, and a treatment area for irrigation or flushing toilets. Proper sizing and installation are crucial for safety and efficiency. Local regulations must be followed.
System Components and Sizing
A grey water system typically consists of a collection tank, which can be a 500-gallon (1893 L) tank for a 2-3 person household. The tank should be elevated to facilitate gravity flow to the filtration system. A filter with a minimum 100-micron rating is recommended to remove particulate matter. A disinfection method such as UV treatment or ozone injection should be used to inactivate pathogens.
Installation and Plumbing
The filtration and disinfection system should be installed in a well-ventilated area, such as an outdoor shed or a dedicated grey water room. The distribution network should be sized to deliver the required flow rate to the treatment area or irrigation system. It is essential to ensure that the system is properly sloped to prevent backflow and contamination. A 2-inch (51mm) pipe with a minimum 1/4-inch (6mm) slope is recommended for gravity-fed systems.
Treatment and Disposal
The treatment area for irrigation or flushing toilets should be designed with a minimum 2-foot (0.6m) separation from the grey water source. A sand filter or a drip irrigation system can be used to treat the grey water before it is used for irrigation. For toilet flushing, a macerator pump can be used to pump the grey water to the toilet tank. Local regulations must be followed for the safe disposal of grey water.
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