Greywater vs dark greywater vs blackwater

MEEB defines blackwater as anything with human waste. but they also classify kitchen sinks and dishwashers as dark greywater. On most practice questions, we get the option of just blackwater or greywater. What would be the sufficient answer to classify kitchen sinks and dishwashers?

Also, is rain water considered greywater? MEEB has this in their own category.

1 Like

Hi @Shikha ,

According to the AIA:

“1. Greywater is lightly soiled water that can be reused for non-potable water uses with minimal or no treatment. Common uses of greywater are irrigation and toilet flushing. Best practice is to use all water for multiple purposes before releasing it.
2. Blackwater is heavily soiled water, from a toilet or commercial kitchen disposal, that is dangerous to humans and cannot be used until treated. Strategies for treating blackwater on-site include engineered composting systems or ecological water treatment systems.”

I would consider residential sinks and dishes as greywater. Commercial are likely Blackwater.

Rainwater is not greywater.

Hope this helps!