reed bed /septic tank

[billi]

Hi all

I have to built a reed bed filter for a small house  to filter grey water and the overflow of the septic tank

The septic tank will be installed next week and the grey water  pipe work as well .

So would you bypass the septic tank  , when installing the grey water ? And let it run direct in the reed bed , or feed the grey water into the septic tank and let this then drain into the reed bed .

I thought first bypass would be right , but i have my reservations now

Any ideas ?

Thanks Billi

[daftlad]

What would be the advantage of bypass?
ta ta

[billi]

That is , why i ask , cause saw a system in my neighbourhood  and they bypassed it ! And i think it makes more sense to let the micro-organism  in the septic tank  do some work  before the reed bed !
So i think it is better to drain the grey water in the septic

Billi

[Billy]

billi, Billy here,

if the grey water inlet is at the top of the tank and the overflow is at the top then surely there will not be much time for the organisms to do much before it goes to the reed bed.  Once the tank is full of course.

I know nothing about it myself so I am just thinking what may happen.

Billy.

 

[billi]

Billy, Billi here

The septic tank will be similar to this design , so i think there will be some mixture of  materials 

[Fintray]

Billi

At least like you said the organisms in the septic tank would start to break down any soaps or detergents in the grey water prior to the water passing to the reed bed which would lessen the amount of work it is required to do.

Billy

Although the inlet pipe to the septic tank is normally positioned slightly higher than the outlet pipe it is generally diverted to the bottom of the tank near the sludge layer so increasing the latency time.

Edit - just saw Billis' reply showing the schematic of the septic tank!

[EccentricAnomaly]

Might be worth looking around the Earthship related sites on this topic.  E.g., get in touch with the people at the Brighton Earthship or these people.

As I understand it Earthship water handling systems have evolved over the years, particularly how they deal with black water.  In the system which was current recently grey water is sent to a planter bed to be processed by the bugs in the gravel and roots.

Originally they used standard composting toilets but now they use water-based septic-tank systems for user acceptability and also acceptability by building authorities.  However, they still only send the black water to the septic tank.  As I understand it there are two reasons: to keep the septic tank as small as possible and to make it last as long as possible between emptying (I think the idea is to avoid having to empty it at all in practice).

By analogy, I can see advantages to bypassing the septic tank for grey water but different building authorities have different ideas about this sort of thing.

[Chanireland]

Hey there been  doing investigations myself will  be doing  similar very soon.
think it  is better  going  through the  tank as it  might  cach  some  grease hair etc having  said  that  maybe  longer  hold  times in  the septic tank  might  give  longer  times for  the  microorganisms  to  do  there  thing.. also  seems  that reedbeds  like  to  be  doused/flushed if  you  have  the  fall on   your  land.  found this  device  which  might  be  helpfull.

http://www.flout.net/rissyplastics2/
also  seems if possible good have a  humus  tank b4 the  reed  bed,  which  i  think is  basically  another   settling  area b4  the  reed  bed.
round  hear they  wouldn't  let  you  use  them  till  recently  now  they  push   them  but sub  surface  horizontal style  and  must  bee 40sm.  quite   a  few  people  have  been just  replacing  there soak  away  areas with them and  planting  willow beds past  the  reed  bed on the  qt..

would  be  interested if  you  just  used  the natural  clay as a  liner or used rubber etc

[martin]

this may help - http://www.johnstonsmith.co.uk/fact17.html

[billi]

Thanks all

It is a existing ex slurry pit (concrete )  ca 8x4 metre and 2metre deep   and will be a vertical reed/plant bed  

something like that

[Baz]

I don't think grease is good for septic tanks or any other method as it floats so you should have a grease trap. Grey water may produce rather large flows from washing machine or bath so is liable to push 'yellow' water out.
A big constituent of grey is phosphates from soap which are more plant than bug food so better straight to reed bed.
In Africa we had a nice mini banana plantation next to the septic tank. It never overflowed nor needed emptying, I wonder why.

[tony.]

In the the few reed bed set ups ive seen that are run by scotttish water the reed bed water is piped from the top and allowed to drain through to the root system using pipework wwith holes in it probably like wavincoil
keeping the pipework above ground makes it easier for clearing blockages
tony

[AlanM]

I have my own reed bed and have planted a few for scottish water.
My thoughts would be to bypass the septic tank as the tank works better without the large inflows from baths/ showers etc, so leaving it to deal only with black water. For something like the kitchen sink, you could install a grease trap by placing a grass/hay box in the pipe which catches the grease as it cools and resolidifies. This is then changed every month or as needed, and then chucked on the compost heap.
The liner i used was Bentomat which is a clay(bentonite) layered inside a type of blanket/textile. Advantage of this is that it is pretty robust wheras rubber or plastic liners can get punctured and therefore require other membranes to prevent stones causing holes.
The reeds are Norfolk reed, Phragmites australis, which you can usually find growing wild.

 Alan 

[billi]

.... Good progress this week

Like said the location is in a slurry tank 18 m2 and 1.6 metre deep

Organized a septic tank  , placed it  and has its own soakaway in the reedbed about 300 mm below the soakaway you can see for the grey water  in the picture

will built a grease trap  ( even some expert told me micro-organism /bacteria will control grease and eat it up )

A few willows cuttings planted    already  and stick 1.5 metre in the   gravel  to allow deep roots

Thanks

Billi