grey water & septics

I just started reading this book yesterday: (The New) Create an Oasis with Greywater: Integrated Design for Water Conservation - by Art Ludwig. Some books manage to suck you in and turn page after page, and this book is one such example. Anyhow, my thread today isn't about the book, more so about a useful short video I stumbled upon on YouTube where two guys talk about septic systems in a way which even kids can understand. I'll leave the link below.

The only two additions I might add (I'm no expert but I've seen examples of this) is to (#1) divert greywater around the septic tank into a separate system of grease trap followed by a reed bed and finally to garden irrigation, and (#2) add another reed bed at the exit of the septic tank so that any blackwater will also get biologically filtered before it seeps into the ground, also making use of this water to irrigate certain crops.



Any feedback is welcome.

Excellent food for thought.  Two comments about your ideas concerning input/output:

Input of Grey and blackwater is problematic, or so I was told. I single handedly dug a hole for approved septic tank 30 yeats back, mostly shovel and pickaxe with coupla weekends of rented jackhammer for a sandstone shelf that stopped my progress.  The task was eventually done, but I don't recommend it unless a severe workout is your target. Along the way an inspector dropped by, he said the flow of greywater was important by ensuring blackwater flows in a normal manner.  He contended that they must work in tandem , to prevent blockage over the years.

And with output, a reed bed won't get nourished if positioned as you mentioned.  At least how I was required to build that one years ago. The leach lines don't dump the fouled  water in one place,  releases slowly through multiple holes, then a membrane before the regulation gravel underneath.  Again, this is only my direct experience so correct me please if I am off base for a 2026 version

Your inspector’s concern about bypassing ALL grey water making the septic not work correctly is partially true. A septic that only serves a toilet can have issues with too many solids and not enough water out inconsistent water, but it is easy to avoid. Putting the kitchen sink to the septic avoids that issue for most people. That is the good reason to treat it as black water, not just because code says so.

When my in-laws had an advanced enviro-septic system installed to replace a failing leach field, they were told that septic tanks, and possibly leach fields, needed a lot of water to keep the biology happy.  Based on input on this thread I did some research to see if I could find a minimum.  To my surprise, I found no minimum indicated anywhere.  Even the manufacturer of the septic system confirmed there was no set minimum.  Obviously if you get too dry you could interfere with the anaerobic biology in the septic tank or dry out the biological mat in the leach field, but evidently the current push on the internet is to minimize water into the tank on my side of the world.

In researching the system we've designed for our new house, I had looked at reed beds and related treatments.  I love how natural they are, but it may be helpful to pass along a hesitancy I had: they need to be replaced or replenished on the order of every 10years or so, plus annual removal of dead plant debris.  One particular version that I thought might be fun to try though in our temperate climate was wastewater gardens.  Our current plan is a worm composting based flush toilet design with both warm-weather surface discharge and freezing weather subsurface discharge that should be able to handle roots of trees, shrubs, and other deep-rooted plants.

R. Scott and Rico Loma, I appreciate the comment about blackwater alone.  Do you have any more information on that?  Is that for the pipe run or the tank?  I've only heard that comment once before, I think related to an advertisement for a dipper device that helped extend the length a toilet-only pipe run could go.  We built our house with greywater plumbing separate from toilet-only blackwater plumbing, and purchased low-flow toilets.  I've wondered if the long pipe run out to our future treatment location could be an issue that might be helped with a higher volume flush toilet.  We hope to build the treatment system next Spring.

I will dig through my files and try to find more verification,  Burton
Like so many things in my life, when I pose questions that are answered by someone older, wiser (not very hard to accomplish) and with visible scars, I tend to believe them as if every word spoken is the Gospel. At times I reflect on this, thinking maybe i am only enthralled by mythology mixed with a dash of common sense , not by facts.  Hmmm....
Will look around after sundown today, sir.  

And yes , that friendly health inspector looking over my septic work in the 90s actually met all those qualifications,  and walked with a pronounced limp

Burton,

It is both. Low flush toilets definitely have issues with longer pipe runs and less than perfect pipe slope, but the long steady flow from the shower usually fixes the problem in normal houses.  The tank is more complicated, depending on pH, nutrient levels, turnover rate, etc. Way above my pay grade to predict.

Burton, I will piggyback on those sentiments.  Family size, details of total effluent,  on and on..... every septic system is a bit unique.  So I can't readily answer your query, you might try forums discussing plumbing issues, or ask a septic service that deals with this directly 365 days a year.