These ideas with the wood chips sound great for graywater... I can imagine hiding them into a raised garden bed, with ornamentals on top, and the percolation chips down below, with a pipe that drains out into an open wetland down hill or built just below with reeds. I have a meadow-beside-the-house, wetland downslope, idea in mind. Where no effluence flows I plan to create a pond... this near my well and to include crushed stone filtration... that is going to be my catchment system for non-drinking water, but I will use it mainly in the garden. My well... has issues. I have to remedy them. Its not such great water, nor is it scarce, that I need to worry about conserving it. What I do need to worry about is protecting it from the pollution of the landscape.
I plan to use woodchips as a material for an extended driveway loop... this is going to be a meadow-forest edge inspired front, to serve to buffer noise and runoff pollution from road and create a place to park... since I dream of turning my home into a bed and breakfast in the future.