Greywater Systems

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• What is “Grey Water”?
• Project Example of a Greywater System

3:20 – 37:29: What is “Grey Water”?

“Grey water”: Water from everyday use – washing machine, shower, bath water, bathroom sink.

“Brown water”: Water from kitchen sink and dishwasher. (Not used as grey water because of possible contamination and toxicity.)

“Black water”: Toilet and sewers

Pros and Cons of Greywater (13:52):

Pros:

• Lower wastewater costs
• Reduces the amount of water that goes to the sewer treatment plant
• Lower water costs
• No overhead spray
• No overspray
• Reduction of waterway pollution
• The bigger the property/indoor water use, the faster payback and return on investment
• After the system is paid off, the system is earning you money each year
• LEED points
• Health risks can be avoided by:
  • Passing water slowly through healthy topsoil for natural purification to occur
  • Design the system so no contact takes place before purification

Cons:

• Retrofitting onto an existing home may not be cost effective
• Some household types get more grey water than others
• No overhead spray (can’t water turf)
• People assume that implementation is simple, which means greywater systems are often overdesigned and abandoned, or underdesigned and abandoned
• No storing untreated grey water for more than 24 hours
• No bleach or hard chemicals
• Plants might not be able to handle the water created
• Potential to create health threats if used improperly

Conditions and regulations (24:55)

Greywater System Components (27:00)

Controller

Emitter (high-flow)

“Rainwater pillow” (harvesting system)

Question: Grey water has a higher level of salt. How to deal with that? (31:20)

Answer: In actuality, grey water is just harvested potable water, meaning it doesn’t have a higher level of salt. However, if you have a water softener that uses salt, you won’t be able to harvest your grey water.

Question: Do greywater systems require the use of special detergents? (34:25)

Answer: Potentially, yes. Research your detergents carefully.

37:30 – end: Project Example of a Greywater System