Grey Flow is a household graywater filter system from Australia, where it’s widely used. It’s a good example to highlight the choices you’ll face in selecting a graywater pump & filter system if you should choose to go that way.
The various Grey Flow models are well designed and robust. The one in the video below lasted 10 years at a home in California. However, the pump eventually gave out, as mechanical components will, and the sole distributor in the state had long since closed up shop. The homeowners could not find a new pump that would wire into the computer controller.
There are numerous other mechanical systems to choose from, and the array of options changes all the time. In this case, the homeowners decided to replace the Grey Flow with an Aqua2Use. (You can see other Aqua2Use systems on our kitchen garden house and conference center bunkhouse pages. We’ve looked at the AquaLoop and IrriGray systems as well.)
Easiest way to build a graywater system
Every graywater system has these basic components:
- 3-way valve (for sewer vs landscape)
- Water conveyance (pipes/tubing)
- Movement mechanism (pump or gravity)
- Filter
The filter is either going to be a basin full of wood chips, or a synthetically produced semi-permeable membrane made of either organic or inorganic material.
The simplest and therefore most robust graywater systems do not involve installing a mechanical filter and pump.
Laundry to Landscape takes advantage of the existing pump in the washing machine, and the mulch basin acts as a biofilter.
If you have sufficient slope in your yard, you can run graywater out of your sinks and showers without relying on a pump at all. For our money, this is quite simply the best way to do it. It does however rely on cooperative topography.
Low-cost graywater filter system comparison
The Grey Flow costs more than the Aqua2Use and cleans the filter for you; the Aqua2Use costs less than the Grey Flow but you clean the filters yourself. That’s the tradeoff.
Both are at the low end of the affordability scale compared to high-tech solutions like the AquaLoop and IrriGray.
Both rely on electricity. The Grey Flow has a bit more complex computerization to it.
Systems that require your involvement often suffer from a lack of participation – people just neglect the occasional routine maintenance. One of our advisors has said that he’s never installed a graywater system that stayed in operation for over a year, because people just stopped paying attention to it.
On the other hand, systems that are designed intentionally as “set it & forget it” bring the problem that the less you’re involved, the less you’ll notice when something goes wrong. You won’t know that the computer chip stopped working, or that the filter’s self cleaning mechanism broke down and all your graywater is going to the sewer, until your plants gradually turn brown and die.
Or you won’t realize there’s a leak. Have you ever seen your neighbor’s automatic lawn watering system early in the morning shooting a tower of water into the air or a jet of water out to the street? They have no idea, and you only saw it because you happened to be out early this one time.
The advantage of a simpler gravity-based graywater system with open pipes going into mulch basins is that all the biological material goes out into the biofilter where it’s composted over time, and there’s only one time each year or so when you need to dig out the beautiful composted earth that used to be wood chips and gunk. There is never any “waste” to be swept away someplace else. You close the loops.
Remember, there is no “away.” When you throw anything “away,” it just moves down the line to someone else’s home.
High-tech vs low-tech
We are big fans of Low-Tech Magazine here at Graywater Central. But we recognize we do still live in the modern world.
The advantage of a mechanical self-cleaning filter is that you don’t have to bother with it. Maybe that suits your lifestyle. As long as our complex civilization continues to operate without a hitch, reliance on high technology will serve.
However, the situation in the Strait of Hurmuz makes it clear that our just-in-time centralized corporate civilization is in fact quite fragile, being only as strong as its weakest link.
A fragile system is one where if you apply volatility to it, it’s harmed:
When you apply stress to your muscles, they become stronger. They are not just resilient, but anti-fragile. When you apply some amount of stress to good community bonds or strong family connections, they become even stronger.
Healthy, robust living systems are inherently anti-fragile. Mechanical commercial systems are usually not even resilient, but fragile – only as strong as their weakest link.
If there were a way for a graywater system to become stronger when volatility is applied, then it too could be called anti-fragile, which is even better than resilient.
If you choose to step up your level of complexity, where you eventually land on the continuum will have to do with these 5 conditions:
- The layout of your yard
- How much money you want to spend
- How much personal involvement you want to have
- Availability & reliability of electricity
- Availability & reliability of tech support
You’ll have to decide for yourself whether “simplicity” means fewer potential failure points, or fewer tasks for you to handle.