A forward-thinking gardenerd wrote in this week:
“I am considering a gray water system to use on a vegetable garden. Is this safe to do? If so, is it considered organic?”
My first thought was, no – it’s not really safe to use, but it might be with the right system. Then I took to the cyberspace waves and found a few bits of information:
In many states it is actually illegal to use gray water on vegetable gardens. You should check with your municipal sewage service to see what laws apply where you live.
In states where gray water systems are legal, they are becoming more sophisticated, to the point that you can divert only certain types of waste water from your home to the yard. For example, collecting water from the kitchen sink or dishwasher isn’t such a good idea because of the food particles and such, but you might want to re-use the water from your bathroom sink or shower. Assuming that you use all-natural, bio-degradable soaps and detergents, this water can be safe to use on plant matter, but I’d still stay away from using it on veggies.
As far as whether it is considered “Organic” or not, I was searching the USDA website for information about gray water, and found nothing. I do remember that our organic standards were at risk several years back, when the government was trying to soften the laws to include sewage sludge as an acceptable form of irrigation and fertilizer. My colleagues and I fought that one long and hard.
The bottom line is that untreated gray water is generally not recommended for use on vegetable gardens. I don’t know a vast amount about gray water systems, or the improvements that are being made every year, but hypothetically speaking if you have a way to treat the water before it goes out to the garden, there may be a way to use it in vegetable gardens. If you are considering installing a system, I would grill your installer about the safety features and treatment process before considering it safe for use out there in the food factory.
Here is a website that has some more information about gray water systems and uses in the home:
I hope that helps. Thanks for writing in.
If anyone out there has a gray water system or insight about this question in California or any other state, share it with us here.