The Use of Greywater

With the recent drought conditions, we have received many phone calls regarding using greywater from household domestic sewerage system to water vegetable gardens. The short answer is no! You cannot use greywater without placing yourself and your family at serious risk of disease or infection.

The provincial Sewerage System Regulation does not allow for any type of wastewater to be used to irrigate any vegetation intended for human consumption, and there are good reasons why. Wastewater from your kitchen sink or shower can be just as infectious as water from you toilet.

When you are preparing food such as chicken, fish, shell fish, and ground meats, you flush blood, particles and water from the food down the sink. These fluids and particles may contain E.coli, salmonella, or several other types of dangerous infectious bacteria that are disposed of as part of the sewerage treatment process. Watering your vegetables with this water reintroduces these bacteria into the food chain.

Shower or bath water can also be very infectious especially if someone with open wounds or an infectious illness is using the tub or shower to bath. You can fill a watering can from the spout while you are showering, which is the same as taking water from the kitchen tap. At least filling your watering can from your kitchen tap doesn’t require that you pay to heat it first.

There is provision in the Sewerage System Regulation for irrigating lawns with effluent through subsurface drip systems. These systems must be designed, installed and maintained by qualified and authorized practitioner.

 by D. C.