Reedbed Sewerage treatment system
All the waste water from the house drains to a septic tank and from there into a 2m x 11m x 600mm reed bed. This is sealed with a plastic liner, and filled with coarse gravel to 150mm above water level, and planted with about 100 reeds of two species (Baumea articulata and Leperonia articulata). However there are a wide variety of wetland species that are effective.
As the reed bed slopes very slightly down towards the outlet, the sewerage takes about 11 days to migrate from inlet to outlet, during which it is broken down by the bacteria living in the root zone of the reeds.
The water then collects in a sump and is pumped underground to a grid of perforated pipes under the orchard area.
In Queensland it is completely legal to pump the outlet of a reedbed system directly onto vegetables, but in NSW it must be discharged underground.
We find the system never smells, and is very low maintenance, with the only chore being to cut down the reeds every few years. If you have a sloping block it can be set up so no pumps are used, though that was not possible in our situation.
Apparently reedbeds also cope rather better with variations in input (for example a long holiday or multiple guests) than the worm farm based systems. However any of these are in my opinion better than the Envirocycle type aerated systems.
Our system was designed by Geoffrey Love of Domaine Environmental (domaine@midcoast.com.au) and the reeds were bought from Bluedale in Wauchope (http://www.bluedale.com.au/)
Hi i like the concept of using a reed bed to filter my gray water and then into the vegie patch and a small dam for fire fighting, using a dry composting toilet so we can reuse the matter also uses .5 of a liter each flush and i want to redirect this also into the reed beds, can you tell me how this system is effected by heavy rains as we have had in QLD and NSW, is the filtration system compramised or do the beds overflow allowing unfiltered waste to spill through native vegetation. or would you just need to build big enough beds to compensate for these rains. great looking system you have.
We also get very heavy rains at times here (over 150mm per hour for several hours one night). i havent found the reed bed overflowing but it obviously pushes a lot of less wel treated water through the system. (we pump sub-surface to the fruit trees and havent every noted any smell or other problem, but i am not sure i would surface irigate the vegies with it. Because the sub surface feed is 600mm deep i dont think there would be any problem.