greywater - greenhouse shower, gravel filled catch basin

Howdy, I have a few questions pertaining to a greenhouse shower design which utilizes a simple gravel-filled catch basin system to under-irrigate raised beds planted with Figs.

Here are some rough sketches of the top and side view of the proposed system:


side view showing the gravel basin in pink, sitting on sideways cinder blocks so water can freely pass.


top view showing the over size of the system (the shower platform in 4ft x 4 ft) and how many figs would likely be planted.

Some more specifics:

depth of basin is .5ft deep x10ft wide x 18ft long

total volume is ~90 cu. ft.

filled with volcanic pumice gravel (lots of pore spaces)

with gravel, anticipated to hold ~300 gallons of grey water

community shower used by 5-10 water conscious people

Low flow shower heads used (1.75 gal. /min.)

Anticipate ~35 gal / day at peak summer use

only shower greywater entering the system (no food, oil etc..)

only biodegradable soaps (such as Brauner's) used

My general question for you is, Overall does this system make sense to you? If not, why not?

What I am not too sure about, which you may be able to provide clarity on:
1. Is it necessary to provide some sort of remediation (constructed wetland, aerobic roots, etc) before the fig roots interact with the grey water?
2. Should I install an overflow for the system in case the basin fills to capacity?
3. Is the pond liner necessary in this system? I would prefer not to have it, and allow the fig roots to go deeper, but am concerned about saturating the soil around the building walls.

1. Is it necessary to provide some sort of remediation (constructed wetland, aerobic roots, etc) before the fig roots interact with the grey water?

No.
2. Should I install an overflow for the system in case the basin fills to capacity?
Yes.

3. Is the pond liner necessary in this system? I would prefer not to have it, and allow the fig roots to go deeper, but am concerned about saturating the soil around the building walls.

Don't know...depends primarily on your soil, secondarily on your climate...better to ask some local builder.

Also, see comments on gravel under
Error: Distribution of grey water through perforated pipe or other system where you can't tell where the water is going
better to use a opened bottom chamber such as an infiltrator or half pipe.

Yours,

Art

I think a greenhouse, like one of these two, could help process greywater in the winter: