Looking at the comments underneath the article I felt relieve that I’m not the only one who finds that making a simple solution complex and overengineered creates all kinds of problems.  When we start adding to many moving parts, and relying on too many energy sources, we find that there is a greater chance of failure, which means that we lose faith in the original solution (in this case, reed beds, sand, and gravel purifying water).  As the chance of failure increases, there is more opportunity for naysayers to exploit shortcomings, translating an inappropriate use of technology to a public health danger in the actual simple concept, which then translates to overcomplicated laws and regulations preventing people from doing the right thing in a slow, simple, and safe scenario.  California greywater laws (until it recently changed to allow residents to apply greywater to landscape without a permit) were a perfect example of the fear factor gone awry!  Arizona greywater laws are a perfect example of creating an atmosphere of safe application of a simple concept without the need to overcomplicate things.

Keep it simple: make yourself an outdoor shower and let the runoff trickle right onto the plants that need it!