Archive for December 6, 2018

Gray Water Laws

Until recently, many cities had no legal distinction between gray and black water, rendering most domestic reclamation efforts technically illegal. But due to increased concerns over droughts and water shortages, some residents and local leaders are pushing for updated laws to allow the regulated use of gray water reclamation.

Would widespread gray water reclamation help or hinder sewage treatment plants such as this one in Santiago, Chili? Some say that without gray water to move waste along, sewage might not make it all the way to the treatment facility.

And where there’s demand, industry can’t be far behind. Companies are now offering gray water systems, pre-construction consultation and custom installation, in addition to working on new technologies.

Still, a gray water reclamation system that is legal in one city may be deemed a health hazard in another. Some regions still classify gray water as sewage, while others provide residents with basic health and safety guides for reusing gray water.

Across the globe, the scope of gray water reclamation varies greatly. Australia and New Zealandhave been ahead of the game for years, providing the local regulations, guidance and education needed for residents to make the most of their waste water. Mexico has begun using treated gray water for irrigation. However, in some less-developed nations, things are less encouraging. While gray water reclamation may not be prohibited by law in poorer nations, often there are far worse substances than soap suds draining into the soil. Ironically, the strict laws gray water advocates are fighting to overcome in developed nations were originally instituted to protect the environment and public health. Read more

Gray Water Usage: Diversion Systems

While the particulars of a gray water diversion or filtration system can vary greatly, several basic steps are commonly used.

hand-activated valve serves as an important first step in many systems, especially the more basic diversion systems. This valve allows a person to decide when water from a bathroom sink, tub or washing machine will be diverted to the garden and when it will go into the sewage system or septic tank. This level of regulation comes in handy to avoid overwatering during times of heavy rain or sending harmful chemicals or diaper water out to the garden.

After gray water is diverted down a system of pipes, its first stop on its trip to the garden is a basic filter — generally a mesh screen — to eliminate larger particles, before entry into a surge tank. The surge tank is used to help regulate flow by temporarily storing large amounts of gray water. This helps ensure a bathtub’s worth of drainage doesn’t all rush into the garden at once, while also preventing it from backing up into the home. Read more