[trebb]

Note the lack of cost vs ROI information.

Yep - my wife used to work for a waste management plant and she told me that, by the time the waste is treated and released, the resultant discharge was clear and safe. Takes more than 5 minutes but a lot more efficient with low energy/natural processes.

[blackdog]

This treatment plant does what a lowland swamp does. The waste water goes in, the plants and micro-organisms eat the waste. The fish and others eat the micro-organisms and plants. The result is clean water at the downstream end. No energy input other than gravity and time.

FWIW, the best tomato plants you can find sprout up in the sludge piles from sewage treatment plants which spend time composting. If you know someone in a municipality who has access to treatment facilities, get them to let you dig out a dozen or so in May. Tomato seeds go unharmed thru the human digestive tract and thru our treatment ponds and end up in the treated solids mounds. We found such seedlings outproduce purchased seeds and plants by about 50%.